Pre-Test Histology Q&A

A 29-year-old woman (gravida 3, para 2) gave birth to a healthy baby after 38 weeks of gestation and delivered the intact placenta spontaneously. The pregnancy was complicated by preeclampsia, but fetal monitoring and ultrasound were normal throughout gestation. The predominant structures shown in the accompanying photomicrograph of the placenta are derived from which of the following?

A married couple, with diagnosed 6-year-long infertility, presents to the fertility clinic. A spermocytogram, confirmed by electron microscopy, reveals that the husband produces all spermatozoa with rounded heads, a condition known as globozoospermia. The missing sperm structure is associated with which of the following?

A 38-year-old (gravida 0, para 0) woman is recently married and pregnant. The zygote is a result of a haploid ovum fertilized by her husband's sperm. Which of the following is required for continuation of the second meiotic division to produce the haploid ovum?

A married couple, diagnosed with infertility present to the fertility clinic. The husband's semen contains only 40 million sperm total with a forward motility index slightly below normal. A hamster egg penetration assay was performed in which hamster eggs are collected and their zona pellucidae are enzymatically removed prior to mixing with sperm. The husband's sperm have normal morphology, but his penetration assay results are 3.7% (normal, 10%). The hamster egg penetration assay requires which of the following?

A 23-year-old woman with a natural menstrual cycle is nearing ovulation. The oocyte of a mature follicle will be induced to undergo the first meiotic division as a result of which of the following hormonal stimuli?

A couple is trying to conceive a child. Following intercourse, which of the following is responsible for the prevention of polyspermy?

Oogonia reach their maximum number at which of the following stages of human development?

A 26-year-old man contracted viral influenza with an unremitting fever of 39.5°C (103°F) for 3 days. Because spermatogenesis cannot occur above a scrotal temperature of 35.5°C (96°F), he was left with no viable sperm after his recovery. Approximately how much time is required for the return of viable sperm to the epididymis?

Implantation of the conceptus at which site in the accompanying diagram of the female reproductive system is most likely to result in excessive, perhaps fatal, vaginal bleeding immediately prior to parturition?

Cells that form the three primitive germ layers are derived from which of the following?

In the developing human embryo/fetus, most of the internal organs begin to form in which month?

The primitive uteroplacental circulation is functionally established during which period of embryonic/fetal development?

The ectoderm is derived directly from which of the following?

Fetal blood from the placenta is about 80% oxygenated. However, mixture with unoxygenated blood at various points reduces the oxygen content. Which of the following fetal vessels contains blood with the highest oxygen content?

A female infant is born approximately 10 weeks prematurely (at 30 weeks) and weighs 1710 g. She has respiratory distress syndrome and is treated with endogenous surfactant. She is intubated endotracheally with mechanical ventilation immediately after birth. Over the first 4 days after birth the ventilator pressure and the fraction of inspired oxygen are reduced. Beginning on the fifth day after birth, she has brief desaturations that become more persistent. She needs increased ventilator and oxygen support on the seventh day after birth. She becomes cyanotic. Further examination, echocardiogram, and x-rays reveal left atrial enlargement, an enlarged pulmonary artery, increased pulmonary vasculature, and a continuous machine-like murmur. Which of the following is the most likely diagnosis?

Which of the following hematopoietic tissues or organs develops from endoderm?

Which of the following processes places the developing heart in the presumptive thoracic region cranial to the septum transversum?

Which of the following is in direct contact with maternal blood in lacunae of the placenta?

A dental hygienist is concerned about the effects of radiation on the in utero development of her baby. During which of the following periods is the embryo most susceptible to environmental influences that could induce the formation of nonlethal congenital malformations?

During a visit to her gynecologist, a patient reports she received vitamin A treatment for her acne unknowingly during the first 2 months of an undetected pregnancy. Which of the following organ systems in the developing fetus is most likely to be affected?

A 32-year-old (gravida 2, para 1) female presents to her obstetrician with abdominal discomfort, increased back pain, shortness of breath, and swelling in her feet and ankles. Ultrasound reveals an amniotic fluid index (AFI) of 27 cm (normal 5 to 24 cm). The condition is caused by which of the following?

The neural plate forms directly from which of the following?

Which of the following forms from paraxial mesoderm?

The cerebral cortex forms from which of the following?

The primordial germ cells that eventually form the oogonia and spermatogonia originate in which of the following?

The structure labeled F in the following diagram is important in embryonic development of humans as which of the following?

Monozygotic twins arise by means of which of the following?

In the developing embryo, the edge of the ectoderm is continuous with which of the following?

Which of the following processes is responsible for fusion of the paired dorsal aortae?

The region labeled with the arrow in the accompanying electron micrograph of the plasma membrane is responsible for which of the following functions?

A 14-month-old boy presents with a fever of 102°F. The child has a longstanding history of recurrent lower respiratory tract infections including bronchitis and pneumonia. Chronic diarrhea is a longstanding problem. His mother reports that she had numerous upper respiratory infections and chronic diarrhea as a young child. A complete blood count, lung function tests, and urinalysis values are all within normal range. Serum immunoglobulin levels are normal for IgG and IgM, but IgA was 25 mg/dL (normal = 40–60 mg/dL). There are numerous neutrophils and other white cells in the stool sample and the stool is cultured for specific bacteria. IgA coats pathogens facilitating repulsion of the negative charge on the cell membrane. That negative charge on the cell membrane is primarily caused by which of the following?

The face labeled by asterisks in the freeze-fracture preparation shown below may be characterized as which of the following?

Band 3 protein exists as a 95-kDa multipass membrane protein that functions as the primary anion exchanger in erythrocytes. Within the red blood cell (RBC) membrane, band 3 binds to spectrin dimers and tetramers indirectly through ankyrin. The spectrin tetramers are bound together by actin and band 4.1 protein, which also binds to band 3 and glycophorin. Null mutations in band 3 occur in the human population. Which of the following is most likely to decrease in the absence of band 3 protein?

A 56-year-old man who drinks a six-pack of beer a day, with higher alcoholic intake on weekends, holidays, and “special days," presents to the internal medicine clinic. He has an abnormal plasma lipoprotein profile. It is known that erythrocyte fluidity is altered in liver disease. Which of the following would increase membrane fluidity in the hepatocytes of this patient's liver?

The asymmetry of the cell membrane is established primarily by which of the following?

A 44-year-old African-American woman calls 911. When the MedAct unit arrives they find a patient with acute shortness of breath and audible wheezing. A physical exam reveals: pulse 115 (normal 60–100), RR 42 (normal 15–20) with signs of accessory muscle use. She is coughing up mucus. Auscultation reveals decreased breath sounds with wheezing on inspiration and expiration. The patient has taken her prescribed medications with no relief of symptoms prior to her 911 call. Her current medication is albuterol, a moderately selective β2-receptor agonist. Which of the following is true regarding those receptors:

A patient is diagnosed with a pleomorphic adenoma of the sub-mandibular gland. The pathologist uses anti-vimentin antibodies with immunocytochemistry to stain the biopsy tissue. One would expect to find vimentin staining in which of the following structures?

Which of the following is the function of the large subunit of the ribosome?

The stability and arrangement of actin filaments as well as their properties and functions depend on which of the following?

A 47-year-old man presents with fatigue and over the next few years became progressively weaker, eventually becoming paralyzed. He encounters severe problems with speech and swallowing. Weakness and paralysis of the thoracic muscles leads to progressive respiratory insufficiency and death. At autopsy transmission electron microscopy reveals fragmentation of the structures delineated by the arrows within motoneurons. Which of the following correctly characterizes these structures?

The primary function of intermediate filaments is which of the following?

A 20-year-old man arrives in the emergency room by ambulance. He has taken an overdose of "goof balls” (Phenobarbital) he obtained from a drug dealer on the street. In a hepatocyte from this patient, what is occurring in the organelle labeled with arrows in the accompanying transmission electron micrograph?

Which of the following mechanisms is used to establish the mitochondrial electrochemical gradient?

A 15-month-old girl is referred for ophthalmologic and neurologic follow-up by her pediatrician. The child has shown a failure to thrive, is microcephalic, exhibits myoclonic jerks, delayed psychomotor development, visual disturbance and seizures. Analysis of fibroblasts from the skin by electron microscopy confirms the presence of fingerprint inclusion bodies. Elevated levels of dolichol are found in the urine. Normally, dolichol is associated with which cellular process:

A boy is born with epicanthal folds, a high forehead, hypoplastic supra-orbital ridges, and upslanting palpebral fissures. He shows growth retardation following birth, he feels like a rag doll when held, and he exhibits neonatal seizures. He also has a ventricular septal defect, glaucoma, cataracts, elevated iron and copper levels in his blood, and hepatomegaly. A liver biopsy is prepared for electron microscopy and shows the presence of empty peroxisomes. The pathologist describes them as peroxisome “ghosts." Which of the following cellular activities should be decreased in the hepatocytes from this patient?

Inhibition of actin assembly by cytochalasins would interfere primarily with which of the following?

Chloroquine is a weak base that neutralizes acidic organelles. In a pancreatic beta cell, which of the following would be a direct effect of chloroquine treatment?

A 6 month-old boy is brought to the pediatric neurology clinic as a referral from a pediatrician concerned about the child's developmental delay, ataxia, hyperventilation, and repeated episodes of vomiting. The parents report one “seizure-like event." Your examination reveals hypotonia, some spasticity, and deafness. You note mild choreoathetosis when the boy is attempting to move. Laboratory results show high lactate in the cerebrospinal fluid, a muscle biopsy shows normal histology, but tests reveal a deficiency in Cytochrome C Oxidase, complex IV. In the electron micrograph below, where would you expect to find that enzyme localized?

A 22-year-old woman presents at the ophthalmology clinic. She describes an initial inability to drive at night because of what she describes as "night blindness.” She says that the deterioration of her vision has continued and she is having difficulty seeing objects on the periphery of her vision. Visual acuity, color, visual field, dark adaptation, and ERG testing is completed. The tests show rod degeneration with limited peripheral vision. She has pigment deposits in the mid-peripheral retina known as “bone spicules". She also has attenuated vessels in the retina and paleness of the optic nerves. An electroretinogram (ERG) is reduced in amplitude. The cause may be related to a failure of opsin and other protein vesicle transport. This transport would occur along which of the following?

Which of the following molecules forms the coating of vesicles involved in transport of secretory vesicles from the trans-Golgi network (TGN) to targets?

A girl to parents of eastern Mediterranean Jewish descent is brought to the pediatric neurology clinic. She appeared normal at birth and is now 6 months of age. There is a loss of peripheral vision and an abnormal startle response to auditory stimuli. She has suddenly shown a loss of coordination and has lost some responsiveness to her environment. She has a cherry-red spot on her macula. Treatments to cure this disease might focus on developing therapies that would do which of the following?

A 14-year-old boy presents with hepatic failure, slurred speech, tremors in the hands and feet, and Kayser-Fleischer rings. A 24 hour urine copper test is 120 micrograms (µg)/24 hours (normal below 100 µg/24 hours) and ceruloplasmin of 15 mg/dL (normal 25 to 50 mg/dL). Liver biopsy reveals 295 μg/g (normal <250 µg/g) dry weight of copper with microscopic changes including glycogen nuclei, microvesicular and macrovesicular fatty changes, steatosis and fibrosis. Genetic studies reveal mutations in the ATP7B gene which has been localized to the late endosome. Such mutations may alter the transport of cargo within late endosomes to which of the following?

A 72-year-old woman is brought to the office of her family medicine physician by her daughter. Her daughter indicates that mom has abrupt mood swings and uncharacteristic moments of anger and aggressiveness. Recently, she drove to her daughter's house for her granddaughter's birthday party and “got lost” returning to her own apartment, eventually completing the 2 mile drive in 2 hours. The patient has recently been unwilling or unable to bathe or brush her teeth regularly and her hair is unkempt. There are grease stains on her blouse. She has lost 15 pounds since her last visit to her physician a year ago. While the patient denies any problems with memory or cognitive ability her daughter reports episodes of forgetfulness and loss of concentration. The pathogenesis of the disease from which this patient suffers, involves the organelles labeled with asterisks in the accompanying electron micrograph. Which of the following processes occurs abnormally in that structure during the progression of this patient's illness?

Endocytosis of low-density lipoprotein (LDL) differs from phagocytosis of damaged cells in which of the following?

In the signal hypothesis, which of the following is the function of the signal recognition particle (SRP)?

Chaperonins regulate protein folding in which of the following ways?

A newborn boy is born with first arch congenital malformations classified as Treacher-Collins syndrome, which is an autosomal dominant inherited disorder. The Treacher Collins-Franceschetti syndrome 1 (TCOF) gene encodes the protein treacle. Treacle is localized to the structure labeled with the arrows in the accompanying transmission electron micrograph. Treacle is most likely involved in which of the following?

Which of the following is true for the process that the dividing cell shown in the electron micrograph below is undergoing?

A 29-year-old woman presents with a 101°F fever, pericardial effusions and Libman-Sacks endocarditis, arthralgias, rash across the malar region of the face ('butterfly rash') that is accentuated by sun exposure; creatinine is 1.7 mg/dL (normal 0.5 to 1.1 mg/dL). Laboratory tests show high titers of antinuclear autoantibodies (ANA), Smith antigen and antinucleosome antibodies in the serum. Which of the following is most likely to be directly affected by the disruption of nucleosomes in this patient?

A G1-phase and an M-phase cell are fused together with a Sendai virus. The result is that the chromosomes in the G1-phase cell condense. Which of the following would be a possible cell biological explanation?

A middle aged anatomy professor went to the hottest Indianapolis 500 race in decades and sat with the sun facing him; there was no breeze. He had a history of borderline high uric acid. When he became dehydrated at the race, it triggered the uric acid crystal formation in his foot. The foot became sore, red, hot and swollen; he could not walk on that foot or even fit into a regular pair of shoes. The race was great and he drank about 2 L of water and soda at the race and another couple of liters when he arrived home. Evidently that was not enough fluid because he was anuric for about 10–12 hours. His physician prescribes colchicine as an anti-inflammatory. A metaphase-blocking dose of colchicine functions through which of the following mechanisms?

The structure labeled A in the accompanying electron micrograph is which of the following?

A 55-year-old man with difficulty urinating, blood in the urine, burning during urination and accelerating prostate-specific antigen (PSA) has a radical prostatectomy. The diagnosis is prostate carcinoma with a Gleason score of 7. Rb, p53, and bcl-2 genes are involved in the development of prostate carcinoma. Which of the following mechanisms may be involved in the loss of cell cycle control that occurs in prostate carcinoma?

Decreased recombination is associated with the production of aneuploid sperm in humans. Meiotic crossover occurs in which of the following stages?

An obese 18-year-old man presents with small firm testes, a small penis, little axillary and facial hair, azoospermia, gynecomastia, and elevated levels of plasma gonadotropins. He has had difficulty in social adjustment throughout high school, but this has worsened and he has been referred for genetic and endocrine screening. The karyotype from peripheral blood leukocytes would most likely show how many Barr body/bodies?

A 20-month-old boy is diagnosed with Hutchinson-Gilford progerial syndrome (HGPS), a severe form of early-onset premature aging. He experienced normal fetal and early postnatal development, but now shows severe failure to thrive, some lipoatrophy, bony abnormalities, a small, beaked nose and receding mandible, hair loss, and speckled hypopigmentation with some areas of tight hard skin. His neurological and cognitive tests are normal. Genetic analysis shows a single spontaneous mutation in codon 608 of the LMNA gene, which encodes both lamin A and lamin C. Which of the following would you most likely expect to be directly affected in cells obtained in a biopsy from this patient?

A newborn boy is diagnosed with Apert syndrome. He has craniosynostosis, hypoplasia of the middle part of his face with retrusion of the eyes, and syndactyly that includes fusion of the skin, connective tissue, and muscle of the first, middle, and ring fingers with moderate fusion of the bones of those digits. There is very limited joint mobility past the first joint. Which of the following were most likely decreased in cells in the inter-digital region of the developing hand of this newborn child?

A 25-year-old man presents with Triple A (Allgrove) syndrome including the clinical triad of adrenal failure, achalasia, and alacrima. The patient shows progressive neurological impairments involving cranial nerves IX, X, XI, and XII, optic atrophy, upper and lower limb muscle weakness, and Horner's syndrome. Causative mutations for the disease have been identified in a gene that encodes the protein ALADIN, a component of the structure labeled with the arrows in the transmission electron micrograph. Which of the following would be directly affected by the mutation?

A male child is born with an absence of the normal structure labeled between the arrows; inclusions of that structure are found within the cells in the photomicrograph. He presents with refractory diarrhea and is chronically dependent on parenteral nutrition. What is the primary function of the structure labeled between the arrows in the photomicrograph below?

Following a positive a-fetoprotein test a child is born with anencephaly. The development of this open neural tube defect (NTD) is caused by failure of primary neurulation. The mechanism for tube formation as occurs during development of the neural tube could best be explained by which of the following?

In the figure below, A is a transmission electron micrograph, and B is a freeze-fracture preparation of a specific cellular structure. Mutations in the proteins that constitute the intramembranous particles labeled in the freeze-fracture image below occur in humans. Which of the following would one expect to occur in the presence of such mutations?

Which of the following is a function of the basement membrane?

A mother brings her son to the pediatrics clinic. The child rapidly developed extensive blistering of the skin shortly after birth. He has painful erosions of the oral mucosa and has refused ingestion. He has also had a history of recurrent infections, with sepsis, on one occasion. Antigen mapping of a skin biopsy shows a split within the lamina lucida of the epidermal basement membrane, and junctional epidermolysis bullosa (JEB) was the diagnosis. In which specific layer of the accompanying electron micrograph would you expect to see the disruption?

Which of the following definitively characterizes the basolateral membrane?

A 54-year-old woman presents to the oral surgeon on referral by her general dentist. She complains of pain during eating or even thinking about food. The pain lasts for about 2–3 hours after eating. Her dentist observes a firm mass in the anterior right side of the floor of the mouth. Her dentures were made by a denturist to save money and her general dentist indicates they fit very poorly. A calcified density is identified in the transverse CT film (see arrow below). The calcification blocks the submandibular duct leading to atrophy of the acini and ducts with reduced secretory function. One would expect which of the following functional changes to occur in association with the basal folds of the striated duct cells?

In the electron micrograph below, the structure labeled D primarily does which of the following?

An 11-year-old boy presents with ciliary dyskinesia, sinusitis, and bronchiectasis. He has had persistent infections and otitis media since birth. A PA radiograph shows dextrocardia, and he has a negative saccharin test. In the cross-section of the cilium shown below, which of the following is primarily affected in this disorder?

The conversion of sliding to bending in the cilium is accomplished by which of the following?

The structure responsible for the linkage of the intermediate filament network of cells to the basal lamina is which of the following?

Where would you expect to find the lesion?

The triplet arrangement of microtubules is found in which of the following?

A 27-year-old, 5-ft-10 in. tall woman presents in the emergency room with a pneumothorax but is afebrile. On physical examination it is noted that she has scoliosis, pectus excavatum, ectopia lentis, and myopia. Her musculoskeletal exam reveals long upper and lower extremities, including the fingers and toes, and an overall gangly, lanky appearance. Her armspan (6 ft 3 in.) noticeably exceeds her height. She has very flexible fingers and a narrow face as well as a narrow mouth with overcrowded teeth. There are stretch marks across her buttocks. Which part of the cardiovascular system would often be adversly affected in this syndrome?

The extracellular matrix and the cytoskeleton communicate across the cell membrane through which of the following?

A pregnant 29-year-old woman diagnosed with type I diabetes 2 decades ago, taking Humulin three times per day, is referred to the ophthalmology clinic. She is complaining of “floaters” and difficulty with night-time driving. Dilated indirect ophthalmoscopy coupled with biomicroscopy and fundus photography detect the presence of proliferative diabetic retinopathy with leaky retinal vessels indicative of increased vascular permeability, growth of new, fragile vessels on the retina and posterior surface of the vitreous and macular edema. Overexpression of fibronectin is a histological marker of diabetic microangiopathy. Which of the following is the primary function of fibronectin in the basement membrane?

A 36-year-old man is referred by his family medicine physician to the pulmonary clinic. He complains of shortness of breath following physical activity and a decreased capacity for exercise. He says that strenuous exercise including yard work is impossible without sitting down and resting every few minutes. After he takes several deep breaths during the physical exam he begins to wheeze. He is not a smoker and as an office worker he is not exposed to dust, fumes or other irritants at work. He appears slightly jaundiced. Serum alpha-1 antitrypsin (AAT) concentration is below normal and is followed up with alpha-1 antitrypsin phenotype and DNA testing indicating one copy of S and one of Z (SZ) mutations and 40% abnormal AAT protein production. Desmosine and isodesmosine are elevated in the urine. Desmosine and isodesmosine contribute to the elasticity of the lung by:

In the synthesis of collagen, the hydroxylation of proline and lysine occurs in which of the following?

Tropocollagen is not assembled in the cell because of which of the following?

The primary function of entactin (also known as nidogen) is to cross-link which of the following?

A 14-year-old boy presents with thin, translucent skin, and a history of easy bruising. Biochemical studies of the patient's dermal fibroblasts cultured from a skin biopsy show abnormal electrophoretic mobility and abnormal secretion of type III procollagen. A mutation in the COL3A1 gene is identified by molecular testing. Which of the following symptoms would be most expected in this patient?

The tissue shown in the photomicrograph differs from white adipose tissue in which of the following ways?

Diseases in which there is a loss of function mutation in integrin expression on lymphocytes would most likely result in:

A 33-year-old homeless woman has been living in an abandoned building eating dried meat, bread from the trash cans outside a bakery. She smokes cigarettes she "bums" from others. She presents at the free clinic with bleeding under the skin particularly around hair follicles with bruises on her arms and legs. She is irritable, clinically depressed, and fatigued with general muscle weakness. Her gums are bleeding, swollen, purple, and spongy. Her incisors and second molars are loose. She has an infected toe, which may be broken. She is afebrile and a glucose finger stick is normal and urine dipstick shows no sugar, protein or ketones. You suspect a vitamin deficiency. What might be the underlying mechanism for the symptoms in this patient?

Which of the following is a major contributor to the tensile strength of collagen?

Laminin functions in which of following ways?

A 40-year-old woman is referred to a dermatologist with more than 100 oval or round red-brown macules on her back. There is a positive Darier's sign. The dermatologist takes a skin biopsy, which is stained with toluidine blue. There are an excessive number of the metachromatically-stained cells labeled with the arrows and shown in the inset to the lower left in the photomicrograph below. Which of the following would be the most likely expected symptom in the patient?

A 46-year-old woman who has been a type I diabetic for 35 years visits your family medicine office. She has foot ulcers on both her right and her left feet. You prescribe Beclaperin gel, a prescription drug for the treatment of diabetic foot ulcers. It contains platelet-derived growth factor (PDGF). Which of the following is the most likely mechanism for the action of PDGF in the improvement of wound healing?

A 55-year-old Caucasian man presented with generalized back pain. His physical examination reveals slight right-sided muscular weakness and a pulse of 78/min, regular; blood pressure 140/82 mm Hg. X-ray examination of the spine showed two wedged thoracic vertebrae, T7 and T8; no osteolytic lesions are observed. Peripheral blood: Hb 11 g/dL, WBC 6.0 × 10/1 (polymorphs 81%, lymphocytes 16%, monocytes 2%, eosinophils 1%), platelets 300 × 10/1 (300 000/mm³). The blood film was normal. The bone marrow shows an increase in the cells shown in the accompanying light micrograph. Other tests were all normal. The cells in the light micrograph synthesize which of the following?

A 44-year-old African-American woman visits her family physician's office. She has come in for a physical examination at the urging of her husband. She has no current complaints and is taking no medications. She is allergic to erythromycin. She works as a software developer and lives with her 52-year-old husband and 12-year-old daughter. She is a nonsmoker; and drinks an occasional glass of wine when she and her husband go out to dinner. She is involved in no regular exercise. Her mother is 66 and suffers from type II diabetes, hyerlipidemia, and hypertension and had a myocardial infarction last year. The patient's father died of a stroke last year at the age of 72. On examination, the patient's blood pressure is 155/100, pulse 84, weight 215 lb (increased from 180 3 years ago), height 5 ft 7 in. In this patient, during the period of weight gain which of the following responses would be most expected in the cells shown in the photomicrograph?

A 65-year-old African-American man who has a history of both urinary tract infections and urinary stones presents at the urology clinic with hematuria. He has a dietary history high in saturated fats and has been exposed to second-hand smoke both at home (his wife smokes) and at work where many of his coworkers smoke. His work as a machinist exposed him to metal parts. Before working as a machinist he worked as a commercial painter. Cystoscopy identified several bladder tumors and was followed by transuretheral resection and biopsy (TURB). The biopsy shows a transitional cell carcinoma 4.5 cm. in diameter staged as “T3aN1M2.” Which of the following would facilitate the processes involved in the “M2" classification?

Intramembranous ossification differs from endochondral ossification in which of the following ways?

A 7-year-old boy is referred to the endocrine clinic with short stature, rhizomelic shortening of the arms and legs, a disproportionately long trunk, trident hands, midfacial hypoplasia, prominent forehead (frontal bossing), thoracolumbar gibbus, and megalencephaly. Radiological examination by MRI reveals caudal narrowing of the interpedicular spaces of T1 and T2 vertebrae and spinal stenosis at L2-L4. Genetic analysis reveals a gain of function mutation, G1138A, in the fibroblast growth factor receptor-3 (FGFR3), band 4p16.3. His parents are requesting the initiation of treatment with growth hormone. The endocrinologist is concerned about harmful growth hormone effects: deposition of abnormally-formed bone and worsening of the patient's kyphoscoliosis. During this child's postnatal development, which of the following is the most likely effect of the FGFR-3 gene mutation?

The molecular basis for shock absorption within articular cartilage is which of the following?

A 16-year-old girl presents to the pediatric genetic and endocrine clinic with short stature, Tanner stage 2 of pubertal development and lack of menstruation. She is 49 in. tall (normal range for age is 59–68 in. mean 64 in.) and weighs 65 lb (normal range for age is 92–158 lb, mean is 126 lb.). She has a short, broad, webbed neck, short fingers and toes, and cubitus valgus. Hormonal profile reveals high levels of the gonadotrophins LH and FSH, and very low levels of estrogen. Ultrasound studies show uterine hypoplasia and poorly-defined gonadal streaks. Genetic analysis shows a 45, X0 pattern. The short stature has been linked to reduced protein expression of the short stature homeobox gene (SHOX). That gene working through specific transcription factors would influence the production of which of the following by the cells delineated by the box in the accompanying photomicrograph.

A 22-year-old man presents to the orthopedic clinic after a referral from his primary care physician. He has a history of recurrent fractures of the humerus and femur and numerous dental caries and associated abcesses. Three years prior to this referral, he was successfully treated with hyperbaric oxygen and surgery for mandibular and maxillary osteomyelitis. Laboratory results include a serum acid phosphatase of 4 units (0.5–2 is normal range by the Bodanksy method) and a hematocrit of 35 (normal range is 41-50%, mean is 47%). Other blood tests are normal. He complains of joint pain. A spine x-ray shows “sandwich” vertebrae with thickening of the vertebral end-plates. X-rays of the long bones show abnormal thickening of the bone. A skull x-ray shows basilar sclerosis. The cell type primarily affected in this patient is shown in the accompanying transmission electron micrograph (A) and labeled as “C” in the light micrograph (B). The activation and stimulation of those cells is involved in which of the following?

LDC is a 45-year-old woman who presents with symmetric polyarticular joint pain, swelling, joint stiffness lasting an hour or more (particularly in the morning), malaise, fatigue, tenderness and pain, and is seropositive for RF. Analysis of synovial fluid reveals synovitis with a white blood cell count of 2500 (normal less than 2000/mm³). Physical examination shows decreased abduction and external rotation of the right and left shoulders. She has some swelling in her right and left knees with full range of motion. Which joint changes will most likely be associated with LDC's disease?

A 42-year-old woman who has been a type I diabetic for 30 years falls when she trips over her vacuum cleaner hose. She tried to break her fall by placing her hand out to save herself and in the process her wrist is forced backwards. She arrives in the emergency room and an x-ray of her wrist is shown in the accompanying x-ray. The first step in the healing of this injury is?

A 55-year-old woman presents with pain in her right hip and thigh. The pain started approximately 6 months ago and is a deep ache that worsens when she stands or walks. Your examination reveals increased warmth over the right thigh. The only laboratory abnormalities are alkaline phosphatase 656 IU/L (normal 23–110 IU/L), elevated 24-hour urine hydroxyproline, and osteocalcin 13 ng/mL (normal 6 ng/mL). X-ray of hips and pelvis shows osteolytic lesions and regions with excessive osteoblastic activity. Bone scan shows significant uptake in the right proximal femur. Which of the following would you include in your differential diagnosis?

A 66-year-old man with no previous significant illness presents with back pain. The patient had felt well except for an increase in fatigue over the past few months. He suddenly felt severe low back pain while raising his garage door. Physical examination reveals a well-developed white male in acute pain. His pulse is 88 beats per minute and blood pressure is 150/90 mm Hg. The conjunctivae are pale. There is marked tenderness to percussion over the lumbar spine. The following laboratory data are obtained: hemoglobin 11.0 g/dL (normal 13–16 g/dL), serum calcium 12.3 mg/dL (normal 8.5–11 mg/dL), abnormal serum protein electrophoresis with a monoclonal IgG spike, urine positive for Bence-Jones protein, and abnormal bone marrow smear. X-rays reveal lytic lesions of the skull and pelvis and a compression fracture of lumbar vertebrae. A potential underlying mechanism for the symptoms observed in this case is which of the following?

A 46-year-old woman presents with pain in the left leg that worsens on weight bearing. An x-ray shows demineralization, and a decalcified (EDTA-treated) biopsy shows reduction in bone quantity. The patient had undergone menopause at age 45 without estrogen replacement. She reports long-standing diarrhea. In addition, laboratory tests show low levels of 1, 25-hydroxyvitamin D, calcium, and phosphorus and elevated alkaline phosphatase. A second bone biopsy, which was not decalcified, shows uncalcified osteoid on all the bone surfaces. On the basis of these data, your diagnosis would be which of the following?

Patients with Cushing's syndrome often show osteoporotic changes. Which of the following is involved in the etiology of osteoporosis induced by Cushing's syndrome?

A newborn girl is born with a small mouth, rather widely spaced eyes and low-set ears. Genetic analysis shows a microdeletion on chromosome 22q11.2 leading to a diagnosis of an anomaly which results from failure of the normal development of the third and fourth branchial pouches during embryonic development. Which of the following would be expected to occur in a child with this anomaly?

A 56-year-old man with a history of hypertension, type II diabetes, and a 2-year history of end-stage renal disease (ESRD) requiring hemodialysis returns to the internal medicine clinic. The patient is hyperparathyroid (parathyroid hormone, 234 pg/mL; normal 10–55 pg/mL) and hypercalcemic (calcium, 12.2 mg/dL). He also has elevated levels of serum urea nitrogen (52 mg/dL), creatinine (5.2 mg/dL), and hyperphosphatemia (phosphorus, 9.1 mg/dL). Serum levels of 1,25-dihydroxyvitamin D are decreased (10 pg/mL; reference range, 24–65 pg/mL). He has been receiving large doses of calcium supplemented with vitamin D to bind the phosphate. He complains of bone and chest pain, increasing fatigue, and extreme dyspnea. His coronary arteries are examined by electron-beam computed tomography (EBCT) and are found to be calcified. The production of calcified soft tissues is mediated by the structures shown in the accompanying transmission electron micrograph. Which of the following is a possible mechanism of action for those structures?

The collagenous protein in bone subserves which of the following functions?

In the diagram of a joint below, the structure labeled C is which of the following?

A 58-year-old Caucasian woman is seen in the endocrine clinic. She has been followed for type I diabetes for the past decade. She sustained a Colles' fracture last year when she fell over the hose while watering the garden. She took hormone replacement therapy (HRT) for 3 years at the start of menopause, but was taken off HRT 5 years ago because of her concerns about ovarian cancer. She drinks three glasses of milk a day and eats other dairy products frequently. She drinks socially, a drink, a glass of wine, or a beer twice/week. She does not smoke. She once was a “runner," but now walks 2 miles twice/week when weather permits. She is 5 ft 4 in. and she weighs 122 lb. Her height has decreased by an inch over the past 5 years and her weight has increased by 12 lb. CBC and blood chemistries are normal. Her “T” score on dual-energy absorptiometry (DXA) is -2 for spine and -2.5 for hip. Bisphosphonates are prescribed. Which of the following is the most likely mechanism of action for the bisphosphonates?

A 12-year-old boy who has grown 3 in. in the past 2 months presents with pain and swelling in his femur just above the knee. Any exercise results in intense pain, and the boy now walks with a limp. X-ray shows a fracture at the distal end of the right femur. Overall, the bone appears immature in the distal femur and there is increased density extending into the metaphysis. There appears to be a soft tissue mass expanding outside the bone. There is also some cortical bone destruction above the lateral condyle. A CT scan shows bone-forming cells in the lung. Once the osteosarcoma cells reach the lungs, enter the lung parenchyma, and clonally expand, they produce bone. In that process, the tumor cells synthesize which of the following?

If a laboratory were designing an effective therapy to prevent the spread of metastatic osteosarcoma, which of the following approaches would most likely be successful?

A 28-year-old woman visits your family medicine clinic complaining of loss of sense of smell, nosebleeds, problems with swallowing, and hoarseness. She admits to “casual, social use” of cocaine on a regular basis since her sophomore year of college when her "boyfriend turned her on to cocaine at a party." You complete examination of her nose with a speculum and otoscope and determine that she has rhinitis (inflammation). There is also perforation and collapse of the nasal cartilage resulting in a “saddle nose" deformity. You also note erosions in the enamel of her front teeth. The breakdown of the nasal cartilage releases collagen fibers primarily of which type?

A 5-year-old boy sustains a tear in his gastrocnemius muscle when he is involved in a bicycle accident. Regeneration of the muscle will occur through which of the following?

In a given muscle fiber at rest, the length of the I band is 1.0 µm and the A band is 1.5 µm. Contraction of that muscle fiber results in a 10% shortening of the length of the sarcomere. What is the length of the A band after the shortening produced by the muscle contraction?

A 66-year-old man who lives alone has a severe myocardial infarction and dies during the night. The medical examiner's office is called the following morning and describes the man's body as being in rigor mortis. The state of rigor mortis is due to:

The sarcoplasmic reticulum of skeletal muscle functions in which of the following?

Observation of a histologic preparation of muscle reveals cross-striations and peripherally located nuclei. The use of histochemistry shows a strong staining reaction for succinic dehydrogenase. The same tissue prepared for electron microscopy shows many mitochondria in rows between myofibrils and underneath the sarcolemma. Which of the following is the best description of this tissue?

In skeletal muscle contraction, the "powerstroke" is initiated by which of the following?

In muscular dystrophy, the actin-binding protein dystrophin is absent or defective. Dystrophin contains similar actin-binding domains to the spectrins (I and II) and a-actinin and has a similar structure. Which of the following is most likely to occur as a result of this deficiency?

DLM is a 32-year-old male homosexual seropositive for HIV. He has HIV-associated periodontitis and intraoral candidiasis. Peripheral neutrophils (PMNs) were isolated from the patient and found to have increased activity as measured by oxidative burst and F-actin assays compared to control patients. Which of the following cellular events would most likely be increased in the peripheral blood PMNs from DLM?

Which of the following is absent in smooth-muscle cells compared to skeletal muscle cells?

In the transmission electron micrograph of skeletal muscle shown below, which of the following is true of the zone labeled C?

The mechanochemical enzyme that can be found on the surfaces of cellular organelles where it mediates movement toward the plus end of microtubules is which of the following?

A 4-year-old boy is referred to the pediatric neurology clinic. His behavior is described as: difficulty in expressing needs, using gestures instead of words and repeating words in place of normal, responsive language. In the examination room he wanders around repeatedly singing "Baa Baa Black Sheep," then crying and laughing for no apparent reason. His parents say he is nervous, excitable, “will not cuddle or be cuddled" and hyperactive. He has no apparent fear of danger and a constant need to spin objects and jumps while twiddling his fingers. MRI showed a significant reduction in total grey matter volume with localized grey matter reductions within fronto-striatal, parietal, and ventral and superior temporal grey matter. FMRI showed an abnormal activation pattern in cortical as well as limbic/striatal areas. The neurons in the frontal, parietal and temporal cortex originate from which region embryologically?

The action potential in the neuron results from which of the following?

An 18-month-old girl flexes the great toe toward the top of her foot and the other toes fan out after the sole of her foot has been firmly stroked by the pediatrician. A year later, the response cannot be evoked by the same stimulus. The change in response is due to which postnatal event?

A 2-year-old boy has an acute inflammatory reaction in the region shown in this photomicrograph several weeks after suffering from chicken-pox. Which of the following is the most likely symptom?

A febrile 52-year-old male patient receiving glucocorticoid treatment presents with vesicular lesions with intense itching, burning, and sharp pain along the back in a specific dermatomal pattern covering his nipple and extending onto the right side of his back. The vesicular lesions do not cross the midline. A Tzanck test is positive. The cause of this illness is the movement of virus from the structures shown in the photomicrograph toward the surface of the skin. This movement occurs in which direction and by which molecular motor?

A 22-year-old male receives a severe, traumatic compression injury to his radial nerve after a motorcycle crash. He shows an advancing Tinel's sign. Which of the following is true about regeneration of axons after his nerve injury?

The nodes of Ranvier increase the efficiency of neural transmission by means of which of the following?

The blood-brain barrier is formed by which of the following?

At the neuromuscular junction, action potentials are coupled to neurotransmitter release by which of the following?

Following a vehicular accident, a 45-year-old male is transported to the emergency room by ambulance. He presents with motor deficits on his right side and is unable to move his right arm and leg and has slurred speech. The injury has most likely occurred on which side and affects which of the following cells, which predominate in the accompanying photomicrograph?

A 36-year-old woman internist completes a 4 week medical mission to rural Bahia, Brazil. Eighteen months after her return she complains of loss of sensation in her hands and feet. Neurologic examination reveals loss of temperature, light touch, pain, and deep pressure on her hands and feet. A hypopigmented macula is present on the dorsum of her hand. A lepromin test is positive and a biopsy reveals inflammation of the structure labeled C in the accompanying photomicrograph. The structure labeled C is which of the following?

The neural crest gives rise to which of the following?

During labor an infant girl went into fetal distress. The child was delivered by a mid-forceps delivery, had seizures soon after births and developed an intracranial hemorrhage with left-sided hemiplegia. She is 6-years-old, has an IQ of about 80, walks with a very severe limp and has a contracted hand on the left side. She barely speaks despite therapy. She is treated with atropine for her sialorhhea. The atropine affects the structure labeled with the arrow to:

A 45-year-old man presents at the neurology clinic with memory loss, mood swings, and clinical depression. Laboratory results reveal a CD4 level of 170/mm³ (normal range is 500–1200) and a CD4 percentage of 12% (normal approximately 40%). His viral load is 12,000 copies/mL. He has previously been treated for pneumocystis pneumonia. The cells in the accompanying photomicrograph, labeled with anti-GFAP, are involved in the progress of this disease. These cells function to do which of the following?

A 47-year-old man is treated with Fluoxetine hydrochloride (Prozac) for clinical depression. This pharmaceutical agent functions through a mechanism that involves the structure labeled “C” in the transmission electron micrograph below. The structure labeled “C” in the accompanying transmission electron micrograph is the site of which of the following?

A 35-year-old woman presents with weakness and spasticity in the left lower extremity, visual impairment and throbbing in her left eye, difficulties with balance, fatigue, and malaise. There is an increase in cerebrospinal fluid (CSF) protein, elevated gamma globulin, and moderate pleocytosis. MRI confirms areas of demyelination in the anterior corpus callosum. Imaging identifies plaques which are hyperintense on T2-weighted and FLAIR images and hypointense on T₁-weighted scans. Which of the following cells are specifically targeted in her condition?

A 33-year-old woman is referred to the neurology clinic complaining of weakness of the eye muscles which began 2 months ago. Subsequently she has had diplopia and increasing difficulty in swallowing. Her speech is slurred and she says that she has difficulty clearly enunciating and pronouncing many words. The physical exam reveals bilateral ptosis and an unstable, waddling gait, and some shortness of breath. Laboratory and diagnostic tests reveal a positive edrophonium chloride (tensilon) test and autoantibodies to the acetylcholine receptor. On the accompanying transmission electron micrograph which region is most affected in this disease?

Vasa vasorum provide a function analogous to that of which of the following?

The cell labeled A is best described as which of the following?

A newborn girl presents with a mutation in the erythropoietin receptor gene which leads to primary familial erythrocytosis (familial polycythemia). During the 5th to 9th months of fetal development, the primary effect was on red blood cell production in which of the following?

A 64-year-old man presents with splenomegaly, lymphadenopathy, persistent fever, night sweats, and weight loss. Bone marrow aspiration and biopsy are scheduled. Which of the following would be the best place to sample bone marrow?

Organs such as the brain and thymus have a more effective blood-barrier because their blood capillaries are of which of the following types?

A 62-year-old African-American man presents with exercise-induced angina. His serum cholesterol is 277 mg/dL (normal <200), LDL is 157 (normal <100), HDL is 43 (normal >35), and triglycerides 170 (normal <150). His BMI is 34 and his coronary risk ratio is 6.84 (normal <5). On cardiac catheterization there is occlusion of the left anterior descending and the origin of the right coronary artery. The disease process is initiated by which of the following?

A 66-year-old man patient who was diagnosed with type II diabetes 10 years ago presents with an aching pain in the muscles of his lower extremity. He says the pain is relieved by rest and worsened by resumed physical activity. His lower limbs appear cold, pale, and discolored, and he has a sore on the skin of his left calf. He has a weak tibial pulse on both sides and poor skin filling from capillaries. In this patient, which of the following functions would be primarily affected in the blood vessel from the lower extremity shown in the accompanying transmission electron micrograph?

A 35-year-old woman's physician orders laboratory blood tests. Her fresh blood is drawn and centrifuged in the presence of heparin as an anti-coagulant to obtain a hematocrit. The resulting fractions are which of the following?

As a hematologist in the clinic, you diagnose a 34-year-old woman with idiopathic thrombocytopenic purpura (ITP). Which of the following symptoms/characteristics would you expect in this patient?

A 47-year-old man presents to his family physician complaining of unusual thirst, increased frequency of urination, dizziness, blurred vision, and numbness in his left foot. His BMI is 32. He reports that his lifestyle is sedentary with very rare exercise. His diet consists largely of what he describes as "fast and junk food." A finger stick reading indicates a blood glucose level of 190 mg/dL and two fasting blood sugars are 156 and 166 mg/dL. Over time, which of the following describes the changes that may occur in the structure labeled "A" in the accompanying light micrograph?

Erythrocytes may have abnormal shapes and sizes in certain diseases. In iron deficiency you would expect to see which of the following?

A 43-year-old woman who has suffered from diabetes for 30 years comes into the clinic. Her hematocrit is 21 and she has a reduced RBC count. Her serum creatinine is 3.0 (normal 2.0 or below). She has a negative pregnancy test and is a nonsmoker. Which of the following would best explain her condition?

Which of the following is a metabolic function of the cells labeled with arrows in the accompanying light micrograph?

You are working in a research laboratory studying cardiovascular function. The studies in that laboratory use a “knockout” mouse in which the gene for atrial natriuretic peptide (ANP) is deleted. Which of the following would you most likely find elevated?

A 43-year-old anatomy professor is working in her garden, pruning rose bushes without gloves. She has a thorn enter the skin of her forefinger. The area later becomes infected and she removes the thorn, but there is still pus remaining at the wound site. Which of the following cells functions in the formation of pus?

A 27-year-old man returns from a climbing trip to Ouray, Colorado. He spent 2 weeks camping with his fellow climbing friends. He is dehydrated and complains that he has been vomiting and has had “foul-smelling" diarrhea since his return from camping. He says that he has noticed several large worms in the vomitus and had a visible worm in his loose stool last week. A stool sample is positive for ova and parasites. How do the structures labeled in the accompanying electron micrograph assist in defending against this condition?

A 52-year-old man, who has smoked two packs of cigarettes per day for the past 38 years, presents with diminished breath sounds detected by auscultation accompanied by faint high-pitched rhonchi at the end of each expiration and a hyperresonant percussion note. He is afebrile. In addition, he shows discomfort during breathing and is using extra effort to involve accessory muscles to lift the sternum. The diminished lung sounds in this patient are primarily due to which cellular events?

Which of the following is the smallest active functional unit (including conduction and air exchange) of the lung?

The lung cells known as “congestive heart failure cells” are which of the following?

A newborn child is diagnosed with Cystic fibrosis (CF). Abnormalities of CF include which of the following?

A 35-week gestation, 5 lb 5 oz female infant was born to a 30-year-old G2P2 woman. The infant had rapid and labored breathing that was viewed as transient tachypnea of the newborn. The infant's 1- and 5-min APGAR scores were 8 and 9, respectively. She initially breastfed, but now has respiratory distress, with a normal pulse and no heart murmurs. She is transported to the neonatal intensive care unit with worsening tachypnea. In that infant, the cells labeled with the arrow fail to do which of the following?

A teenage girl presents in the emergency room with paroxysms of dyspnea, cough, and wheezing. Her parents indicate that she has had these "attacks" during the past winter, and that they have worsened and become more frequent during the spring allergy season. Which of the following cell types and their location is correctly matched to a function it may perform in this patient's disease?

Signal transduction in the epithelium lining the region with the arrow differs from that in rod cells stimulated by light in which of the following ways?

Which of the following is part of the minimal blood-air barrier in the lungs?

Major defense mechanisms of the respiratory system include which of the following?

A 56-year-old man presents to his family medicine physician. He is a 41 year pack/day smoker. He reports that he has had a "typical smoker's cough" for years; however, the morning cough has turned into a chronic productive cough with hemoptysis. He has dyspnea, chest pain, cachexia, increasing dysphonia. He has been treated for 4 respiratory infections in the past 18 months. Examination of the sputum reveals the presence of malignant cells confirmed by fine needle aspiration. Imaging reveals a tumor that is 3 cm in greatest dimension, surrounded by lung parenchyma. Bronchoscopic evaluation reveals a cavitary lesion of a proximal bronchus. Surgical resection is completed and the pathologist classifies the tumor as a T1, N2, MO nonsmall cell lung cancer (NSCLC), specifically a squamous cell carcinoma. Tumor vascularity assessed by bronchial arteriography (BAG) and immunocytochemistry indicates a highly vascular tumor with many microvessels. Vascularity of the tumor is inhibited by upregulation of which of the following?

A 43-year-old woman presents with a cyst on her labia majora with foul-smelling drainage. She says the drainage occurs spontaneously and recently the cyst has enlarged and has become painful. The cyst is associated with the structure in the photomicrograph delineated by the arrow. The mechanism of secretion normally used by this structure is which of the following?

Merkel cells are modified epidermal cells that function primarily in which of the following?

The layer at the tip of the pointer is which of the following?

SWL is a 37-year-old woman with a suspected Schwanoma. The radiology report reads as follows: “a soft tissue mass to the right of L1 at the level of the L1-L2 neural foramen. The mass cannot be differentiated from the L1 nerve root and extends into the neural foramen such that it has a ‘dumbbell' configuration with components lateral to the neural foramen, a waist in the foramen itself, and a component within the spinal canal to the right of the thecal sac." The neurologist, Dr. Jane Motumbo, applies the base of a vibrating 128 CPS tuning fork to the skin overlying SWL's right and left thighs and asks her to describe the sensation. She asks SWL to close her eyes and then to tell her whether the tuning fork is vibrating or not. Vibration sense is impaired on the right side. Tests for pain and temperature indicate impairment on the left side. Using the tuning fork, Dr. Motumbo is primarily testing the function of which of the following sensory receptors?

A woman presents with blisters on her back and buttocks (Figure A). She has autoantibodies to one of the cadherins that is distributed as shown in Figure B. The cause of this disease is disruption of which of the following?

A first-year woman medical student presents with patches of raised red skin covered by a flaky white buildup on her knees and elbows. The patches enlarge and become itchy and burning immediately before and during major exams during the first year of medical school. A biopsy from her skin is shown below. Which of the following is the underlying cause of this disorder?

A 52-year-old woman patient presents with severe blistering over her buttocks. Analysis of sera with immunofluorescence demonstrates autoantibodies localized as shown in the accompanying photomicrograph. A biopsy indicates extensive inflammatory infiltrates with numerous eosinophils present. You are asked to look at the biopsy. The underlying cell biological mechanism most likely involves an abnormality in which of the following structures?

A boy is born with blonde hair, blue eyes and very fair complexion, dramatically lighter features than both of his parents. A PKU test is positive. The boy's lighter skin and hair is most likely due to which of the following?

A 50-year-old woman presents to the family medicine clinic. She admits to drinking a six-pack of beer each day with a little more intake on weekends. Lab tests show elevated ALT/SGPT and AST/SGOT. Her sclerae appear jaundiced and her serum bilirubin is 2.5 mg/dL (normal 0.3-1.9 mg/dL). A biopsy of her liver shows eosinophilic intracytoplasmic inclusions (Mallory bodies) derived from intermediate filament proteins. What is the most likely source of Mallory bodies?

The resting parietal cell does not secrete acid for which of the following reasons?

Enteroendocrine cells differ from goblet cells in which of the following ways?

In regard to the enteroendocrine cells and the cells composing the enteric nervous system of the gut, which of the following applies to both types of cells?

A 17-year-old with counterfeit identification has a piercing done at a local tattoo/piercing establishment. She chooses to have a stainless steel barbell inserted in the piercing through the anterior 2/3 of her tongue. There is damage to the structures shown in the associated photomicrograph. Primary afferents from those structures travel through which of the following cranial nerves? _____

Hirschsprung's disease and Chagas' disease result in disturbance of intestinal motility. The site of this disruption is most likely which of the layers on the accompanying micrograph?

A 48-year-old woman presents to the allergy and rheumatology clinic with itching eyes, dryness of the mouth, difficulty swallowing, loss of sense of taste, hoarseness, fatigue, and swollen parotid glands. She reports increasing joint pain over the past 2 years. She complains of frequent mouth sores. Laboratory tests show a positive antinuclear antibody (ANA) and rheumatoid factor levels of 70U/mL (normal levels less than 60U/mL) by the nephelometric method. A parotid gland biopsy shows inflammatory infiltrates in the interlobular connective tissue with damage to acinar cells and striated ducts. In this case, resorption of which of the following will be most altered by destruction of the striated ducts?

Which of the following is the primary regulator of salivary secretion?

A young child presents with hepatomegaly and renomegaly, failure to thrive, stunted growth, and hypoglycemia. A deficiency in glucose 6-phosphatase is identified and the diagnosis is von Gierke disease. In the liver, the structures labeled with the arrows in the accompanying transmission electron micrograph accumulate during this disease. What are the labeled structures?

The branching structures shown in the photomicrograph below (a scanning electron micrograph taken from the region between two hepatocytes) are involved in which of the following?

The following question refers to the photomicrograph below of a plastic-embedded, thin section. The structure labeled A is which of the following?

A pathologist views the following tissues (A and B) in a biopsy. She determines that the tissues are normal. The presence of both of these tissues indicates that the sample was taken from the region of the junction between which of the following?

A 52-year-old woman with a provisional diagnosis of celiac disease presents with bouts of diarrhea and extreme fatigue. Verification was sought through performance of esophagogastroduodenoscopy to obtain small bowel biopsies. Biopsies of the region shown in the accompanying light micrograph disclose hyperplasia of the structures labeled with the asterisks. The labeled structures produce which of the following?

Inflammation in the organ shown in the photomicrograph may result in referred pain to which of the following areas?

The cells labeled with the asterisks in the center of the transmission electron micrograph below function in which of the following processes?

In hemolytic jaundice, the structure labeled with the arrow in the accompanying photomicrograph will contain which of the following?

A 4-day-old boy weighing 7 lb, 6 oz is brought to the emergency room by his parents. The examining emergency room physician notes that his skin and sclerae are icteric. A blood test indicates elevated unconjugated bilirubin in the serum. The elevated bilirubin levels in this patient are most likely the result of which of the following?

A 42-year-old woman (5 ft, 3 in., 170 lb) complains of sudden onset of severe pain in the right upper abdomen “under the ribs” accompanied by sweating, nausea, and a feeling of imminent collapse. The pain lasts for about 2 hours and then persists as a dull ache. When seen several hours later, she has normal bowel sounds, is tender throughout the abdomen, especially in the right upper quadrant, and is faintly icteric. She has noticed her urine is darker than usual but has not passed stool recently. She recalls occasional episodes of "indigestion" referred to the right upper abdomen and radiating to the shoulder. This has occurred especially after eating fried foods or after eating a meal following a long period of fasting. She has no fever but is anxious and tachycardic. The test results available are a blood count and blood chemistry including liver enzymes, alkaline phosphatase, and bilirubin. She has a WBC of 10,000. Her cellular hepatic enzymes are: AST/SGOT = 52 (normal 3–33) and ALT//SGPT = 70 (normal 4–44), alkaline phosphatase = 300 (normal 17–91), bilirubin = 6.3 (normal 0.2–1.0). Which of the following is the most probable diagnosis ?

A 14-month-old girl is brought to the pediatric dentistry clinic because her erupted deciduous teeth are opalescent with fractures and chips in the surface. X-rays reveal bulb-shaped crowns and thin roots. Structure D on the diagram is abnormally large in her teeth. The structure labeled "B" on the diagram is prepared for histology and shows disoriented, irregular, widely-spaced tubules with wide vascular channels. Which of the following applies to the layer labeled “B?”

A 39-year-old woman presents with dyspnea, fatigue, pallor, tachycardia, anosmia, and diarrhea. Laboratory results are: hematocrit 32% (normal 36.1–44.3%), MCV 102 femtoliters (fL) [(normal 78–98 fL)], 0.3 % reticulocytes (normal 0.5–2.0%), 95 pg/mL vitamin B12 (normal 200–900 pg/mL), and an abnormal stage I of the Schilling test. Autoantibodies are detected to a cell type that is found in a region shown in the accompanying diagram. In which region would those cells be found?

A 43-year-old man who recently returned from a trip to rural Peru presents with severe watery diarrhea, vomiting, and dehydration. He also has marked leg cramps and has lost 8 lb since his return from the trip. Fecal culture is positive for V. cholerae. How does this bacterium exert its effect?

A 35-year-old man visits his family medicine physician complaining of bloating, a sense of urgency, cramping abdominal pain, meteorism, diarrhea with excessive flatulence several hours after ingestion of milk or dairy products. He says that he has always enjoyed milk and dairy products without any problems, but now eating them causes him abdominal distress. In this disorder, the area shown by the arrows would have a decrease in which of the following?

The adrenal cortex influences the secretion of the adrenal medulla by means of which of the following?

A pheochromocytoma is a common tumor of the adrenal medulla. In the presence of this tumor, which of the following symptoms would most likely be observed?

Which of the following applies to the gland shown in the photomicrograph and labeled with the arrow in the MRI below?

During the physical examination of a newborn child, it is observed that the genitalia are female, but masculinized. The genotype is determined to be 46,XX. Which of the following is the most likely cause of this condition?

A 33-year-old woman visits the office of her family medicine physician. Her chief complaint is nervousness. She describes her nervousness as increasing over the past 6 weeks. She says that her children and husband describe her as atypically "easy to anger.” She says that she now easily loses her temper and often cries for little or no apparent reason, and she has developed a tremor in her right arm. She has lost 22 lb since her last office visit 9 months ago and indicates that she has not changed her diet. She describes herself as always “hot." You observe that her eyes protrude and appear red and inflamed, and she describes her eyes as feeling "dry.” Your examination reveals asthenia, tachycardia, and pretibial myxedema. A biopsy of the organ shown below shows an increase in lymphoid cells. An array of tests is completed. To which of the following would you expect to detect autoantibodies within this organ?

Which of the following cells or parts of the pituitary are derived embryologically from neuroectoderm?

A pituitary adenoma is likely to result in which of the following?

A tumor in the specific region denoted by the asterisks will most likely cause which of the following?

Refer to the photomicrograph below in answering this question. The low-magnification micrograph (A) and is from the same organ as the high-magnification micrograph (B). A 30-year-old woman presents with chronic fatigue that has worsened during the past months. She has muscle weakness and describes a loss of appetite with a 15-lb weight loss since her last visit. She admits to having "no appetite and eating less," but "craves salty foods" when she is able to eat. She is nauseous much of the time and sometimes vomits after eating. Her bowel movements are loose with frequent diarrhea. Her blood pressure is low and she becomes dizzy when standing. It is the middle of winter in Kansas and she has a healthy tan. The darkening of her skin is most visible in her skin folds and at her elbows, knees and knuckles. She describes being “irritable and depressed” and has had very irregular menstrual periods over the 6 months, which she attributes to early menopause. However, she reports no "hot flashes." Which of the following would occur in the regions of a biopsy specimen labeled in the accompanying photomicrograph?

The region labeled C is not a good candidate for transplantation compared with other endocrine glands for which of the following reasons?

A 45-year-old woman, who works as a corporate executive, presents with the primary complaint of "always being tired.” She comments that she has been tired for 4 months even though she is sleeping more. She complains of being unable to finish household chores and “dragging at work." She indicates that she is often constipated and is intolerant to cold. She is continuously turning the thermostats in the house and work to higher temperatures, to the dismay of family members and coworkers, respectively. She also complains that her skin is very dry; use of lotions and creams have not helped the dryness. A biopsy of the organ shown in question 227 indicates dense lymphocytic infiltration with germinal centers throughout the parenchyma. A battery of tests is carried out. You would expect which of the following?

Measuring T3 levels does not necessarily accurately depict the thyroid's ability to secrete T3 for which of the following reasons?

Elevated estrogen levels during the menstrual cycle result in which of the following?

A patient biopsy is reviewed by a pathologist. She diagnoses the tumor as originating from the cells delineated with the star. The tumor would most likely produce which of the following?

The structure or structures labeled B in the photomicrograph from the reproductive system is which of the following?

The function of the organ shown in the photomicrograph is which of the following?

What organ is pictured below?

Malignancies most frequently arise from which portion of the organ shown in the photomicrograph below?

Naturally occurring, nonpathologic cervical eversions (“erosions”) are usually naturally corrected by reepithelialization. These eversions are most prevalent in which one of the following reproductive classifications of women?

The organ shown in this photomicrograph is responsible for production of which of the following?

The organ in the photomicrograph performs which of the following functions?

Which of the following is independent of testosterone or other androgens?

A 26-year-old woman is in her last trimester of a normal pregnancy. Synthesis of milk by her mammary glands specifically requires which of the following?

The urologist may describe the reattachment of a severed vas deferens (vasovasostomy) as successful, more than 90% of the time. However, it is unsuccessful from the patients' point of view since a much lower percentage of these men can father a child. The difference in success rate is due to which of the following?

A 29-year-old woman is trying to become pregnant. She presents with irregular menstrual cycles and heavy, prolonged, irregular uterine bleeding and undergoes an endometrial biopsy. The biopsy has the appearance shown in the photomicrograph below. Which of the following is characteristic of this stage of the menstrual cycle?

The low pH in the vagina is maintained by which of the following?

A 33-year-old woman with an average menstrual cycle of 28 days comes in for a routine Pap smear. It has been 35 days since the start of her last menstrual period, and a vaginal smear reveals clumps of basophilic cells. As her physician, you suspect which of the following?

If the hormone necessary for maintenance of this structure in the photomicrograph below were absent 12 to 14 days after ovulation in a human female, which of the following would be the result?

The accompanying diagram shows a cross section of a developing human endometrium and myometrium. Hormonal ratios control the development of which of the labeled vessels?

Cells in the layers labeled A and C in the figure below secrete plasminogen activator and collagenase that is required for which of the following?

Secretions from the organ shown below carry out which of the following functions?

Acetazolamide, a member of the sulfonamide family of antibacterial drugs, blocks carbonic anhydrase activity. Which of the following would most likely occur after treatment with acetazolamide?

In the accompanying transmission electron micrograph of the renal corpuscle, which of the following is the function of the cell marked with an asterisk?

A 15-year-old boy presents with hematuria, hearing loss, lens dislocation, and cataracts. Genetic analysis shows a mutation of the COL4A5 gene. A renal biopsy is performed. In which area labeled A-E on the accompanying electron micrograph would you expect to see the primary site of damage?

A 14-year-old girl presents in the pediatric nephrology clinic with fatigue, malaise, anorexia, abdominal pain, and fever. She reports a loss of 6 lb in the last 2 months. Serum gamma globulin as well as the immunoglobulins: IgG, IgA, and IgM are all elevated. She is diagnosed with bilateral photophobia as a result of nongranulomatous uveitis. Her serum creatinine is 1.4 mg/dL (normal: 0.6 to 1.2 mg/dL) and urinalysis of glucose and protein are 2+ on dipstick test and are confirmed by the laboratory at 8.0 g/dL and 0.95 g/dL, respectively. A renal biopsy is prepared for light and electron microscopy. Lymphocytes, plasma cells, and eosinophils are found within infiltrates with pathological change in the tubular basement membrane. The cell most affected is shown in the accompanying transmission electron micrograph. Which of the following is a correct statement about this cell?

The arrows in the accompanying scanning electron micrograph of the renal glomerulus indicate which of the following?

In a patient with diabetes mellitus of 30 years' duration, complications related to kidney function may include which of the following?

Which of the following is found exclusively in the renal medulla?

In the surgical procedure known as LASIK, the shape of the cornea may be flattened. This will result in which of the following?

Retinal detachment most commonly results from which of the following?

Visual transduction involves which of the following?

The retinal pigment epithelium (RPE) is characterized by which of the following?

Which of the following occurs in diabetic retinopathy?

Which of the following statements describes the structure labeled B in the figure below?

Data from the photoreceptors are integrated in which of the following?

The direction in which vestibular hair cell stereocilia are deflected is important for which of the following reasons?

Which of the following is directly involved in sound transduction?

Perilymph is located in which of the following structures?

In the structure shown below, the structure labeled D is responsible for which of the following?

Which of the following is the function of the vestibular membrane?

Detection of angular acceleration is accomplished by which of the following structures?