Exam Instructions for Module Assessment

The breakdown of oxyhemoglobin releases oxygen for tissue use. This happens in conditions of low oxygen levels, low pH (acidity), and actively metabolizing tissues, all of which increase the demand for oxygen.

A transfusion reaction occurs when incompatible blood types are mixed. The safest combination is when the donor's blood type has no antigens that the recipient's immune system will recognize as foreign.

Thrombin is a key enzyme in blood clotting. It converts fibrinogen, a soluble protein in plasma, into fibrin, an insoluble protein that forms a mesh-like structure trapping blood cells and platelets, ultimately forming a clot.

Erythropoietin is a hormone produced by the kidneys. It stimulates the production of red blood cells in the bone marrow, which carry oxygen throughout the body.

Veins act as capacitance vessels because they can stretch and expand to accommodate larger volumes of blood. This allows for blood to be stored in the veins, especially when the heart contracts.

The sinoatrial (SA) node, located in the wall of the right atrium, acts as the primary pacemaker of the heart. It generates electrical impulses that initiate the heart's rhythmic contractions.

Blood flow resistance is influenced by the diameter of the blood vessel, its length, and the viscosity (thickness) of the blood. Narrower vessels, longer vessels, and thicker blood all increase resistance to flow.

Blood vessel diameter is the primary factor that influences blood flow. Vasoconstriction (narrowing) increases resistance, while vasodilation (widening) decreases resistance.

The heart muscle is supplied with oxygen and nutrients by the coronary arteries, which branch off from the aorta. These arteries provide a vital blood supply to the heart tissue.

Growth hormone (GH) plays a significant role in metabolism. It stimulates protein synthesis, increases tissue mass, promotes fat breakdown, and increases blood glucose levels, all contributing to overall growth and development.

Antidiuretic hormone (ADH), also known as vasopressin, acts on the kidneys to increase their permeability to water. This allows for more water to be reabsorbed back into the bloodstream, reducing urine volume and conserving water.

Cortisol, a steroid hormone, is produced by the adrenal cortex. It plays a crucial role in stress response, regulating blood sugar levels, and influencing the immune system.

Melatonin, a hormone produced by the pineal gland, helps regulate the body's internal clock, also known as the circadian rhythm. It is involved in controlling sleep-wake cycles and other biological processes.

Aldosterone, a mineralocorticoid hormone produced by the adrenal cortex, is primarily regulated by the renin-angiotensin-aldosterone system and blood potassium concentration. It controls sodium and potassium balance in the body, influencing blood pressure and fluid volume.

Lymph is propelled through the body by various mechanisms. Contractions of smooth muscle in lymph vessels, muscle contractions, and changes in thoracic pressure during breathing all contribute to lymph circulation.

The spleen is a vital immune organ. It removes worn-out red blood cells, stores blood, and filters microorganisms from the blood. It is not involved in fat absorption, which is done by the small intestine.

Red blood cells are not present in lymph. This is because the lymphatic system is a separate circulatory system that does not transport red blood cells, but carries white blood cells, proteins, and fluids.

Thymosin is a hormone produced by the thymus gland, not the thyroid gland. It plays a crucial role in the development and maturation of T-cells, which are essential components of the immune system.

The residual volume is the amount of air that remains in the lungs even after a forceful exhalation. It helps to keep the alveoli open and prevents lung collapse.

Increased carbon dioxide levels in the blood make it more acidic. This triggers chemoreceptors to send signals to the brain, increasing the rate and depth of breathing to expel excess carbon dioxide and restore the blood's pH balance.

Carbon dioxide dissolves in blood, forming carbonic acid, which increases the hydrogen ion concentration, making the blood more acidic. This is why increased CO2 levels lead to a decrease in blood pH.

Surfactant, produced by septal cells in the alveolar walls, is a substance that reduces surface tension in alveoli, preventing them from collapsing and allowing for efficient gas exchange.

The larynx, or voice box, serves as the pathway for air, aids in sound production, and prevents food and liquids from entering the trachea. However, it does not serve as a common passageway for food.

Peristalsis is a series of coordinated muscle contractions that propel food through the digestive tract. It's like squeezing a toothpaste tube, moving the contents forward.

Most nutrient absorption occurs in the small intestine, where the vast surface area provided by villi and microvilli allows for efficient uptake of digested food molecules into the bloodstream.

The pancreas, an accessory organ of digestion, also produces hormones like insulin and glucagon, which regulate blood sugar levels. It plays a crucial role in both digestive and endocrine functions.

The alimentary tract, the digestive system, is composed of four layers of tissue: the mucosa (innermost), submucosa, muscularis, and serosa (outermost). Each layer has specific functions in digestion.

The digestive tract layers are arranged from outside to inside: serosa, muscularis, submucosa, and mucosa. This ensures proper functioning and protection of the digestive organs.

Accessory organs of digestion support the main organs of the digestive tract. They include the salivary glands, liver, gallbladder, and pancreas, all contributing to the breakdown and absorption of food.

The esophagus, being the passageway for food, is lined with stratified squamous epithelium, which is tough and resistant to abrasion from food particles.

Chief cells in the stomach secrete digestive enzymes, specifically pepsinogen, which is converted to pepsin (a protein-digesting enzyme) in the acidic environment of the stomach.

The stomach's primary functions are to secrete gastric juices, produce gastrin (a hormone that regulates digestion), and secrete intrinsic factor (essential for vitamin B12 absorption). However, it does not initiate deglutition (swallowing).

Active transport is a process that requires energy to move molecules against their concentration gradient. Glucose, amino acids, and dipeptides are absorbed through active transport, while water moves passively through osmosis.

Microglia are specialized macrophages that reside in the central nervous system (CNS). They act as the immune defense cells of the brain and spinal cord, removing debris and pathogens.

Neurons, unlike most other cells, cannot replicate after maturity. While glial cells can divide after maturity, they remain specialized and provide support to neurons.

The correct pathway for impulse conduction in a neuron is from the dendrite, receiving signals, to the cell body, processing information, and then to the axon, transmitting the signal to other neurons or target cells.

The pia mater is the innermost layer of the meninges, a set of three membranes that surround the brain and spinal cord. It is closely attached to the brain and spinal cord, providing a delicate protective layer.

The thoracic region of the spinal nerves is not a plexus. The other listed regions (cervical, brachial, lumbar) form plexuses, which are networks of interconnected nerves that allow for complex movements and sensory functions.

The correct flow of signals in a reflex arc is from the sensory neuron, detecting the stimulus, to an interneuron, which processes the signal, and then to the motor neuron, executing the response.

The brain has four ventricles, fluid-filled cavities within the brain that contain cerebrospinal fluid (CSF), which cushions and nourishes the brain.

Parasympathetic stimulation, part of the autonomic nervous system, generally promotes relaxation and rest. It slows heart rate, but the other options (contraction of urinary bladder, relaxation of digestive sphincters, increased salivation) are all effects of parasympathetic stimulation.

The cerebral cortex, the outer layer of the cerebrum, is where somatic senses are 'mapped'. This means that different areas of the cortex are responsible for processing sensory information from different parts of the body.

The cerebellum, located at the back of the brain, plays a crucial role in coordinating skilled muscle activity, maintaining balance, and regulating muscle tone. It ensures smooth, coordinated movements.

The osteon, or Haversian system, is the basic structural unit of compact bone. It contains a central canal that houses blood vessels and nerves, which supply nutrients and remove waste from bone cells.

Osteoclasts are bone-resorbing cells that break down bone matrix. This process is essential for bone remodeling, allowing for new bone formation and repair.

The lumbar vertebrae are the largest and sturdiest of the vertebrae. They bear the weight of the upper body and are located in the lower back region.

Intervertebral discs are composed of fibrocartilage, a tough and resilient type of cartilage that acts as shock absorbers between vertebrae, allowing for flexibility and preventing bone-on-bone contact.

A fontanelle is an unossified area in an infant's skull. These soft spots allow for the skull to expand as the brain grows during infancy. They gradually close as bone ossification progresses.

The occipital bone, located at the back of the skull, articulates with the first vertebra (atlas) to provide support for the head and allow for head movement.

The manubrium is the upper part of the sternum, or breastbone. It articulates with the clavicles (collarbones) and the first two ribs, providing structure for the chest.

The patella, or kneecap, is a small bone that sits in front of the knee joint. It protects the knee joint and helps with knee extension.

The clavicle is the collarbone, a long bone that connects the shoulder blade to the sternum. It helps stabilize the shoulder joint and allows for arm movement.

Opposition is a unique movement associated with the thumb, allowing it to touch the other fingers on the same hand. This movement is essential for grasping and manipulation.

The joint between the axis (second vertebra) and the atlas (first vertebra) allows for rotation of the head, enabling us to turn our heads left and right.

Perimysium is a connective tissue layer that encloses muscle fascicles, which are bundles of muscle fibers. It helps organize and hold muscle fibers together, allowing for coordinated muscle contractions.

The sarcolemma is the plasma membrane of a muscle fiber. It plays a crucial role in transmitting nerve impulses to the muscle fiber, triggering muscle contraction.

Skeletal muscles are controlled by somatic motor neurons, which are part of the voluntary nervous system. These neurons transmit signals from the brain and spinal cord to skeletal muscles, initiating muscle contractions.

The clavicle is part of the appendicular skeleton, which includes the bones of the limbs and girdles. The axial skeleton includes the bones of the head, neck, and trunk.

Fusion of pronuclei, the male and female haploid nuclei, occurs during fertilization. This event marks the beginning of a new diploid organism, with genetic material from both parents.

Blastomeres are the individual cells that result from cleavage, the rapid cell division of the zygote. These cells become smaller with each division, forming a morula, then a blastocyst.

The kidney is the primary organ of the urinary system, responsible for filtering waste products from the blood, regulating fluid balance, and producing urine.

After leaving the glomerular capsule, filtrate enters the proximal convoluted tubule, the first segment of the renal tubule where most of the reabsorption of nutrients and water occurs.

Reabsorption in the kidneys is the process of moving substances from the renal tubule back into the bloodstream. This helps to conserve essential nutrients and water, while waste products are excreted in urine.

Antidiuretic hormone (ADH) causes the body to conserve water by increasing reabsorption in the kidneys. It does not cause the body to secrete excess water, which is primarily regulated by other mechanisms.

Filtration in the glomerulus is a passive process driven by pressure. Substances move from the blood in the glomerulus into the glomerular capsule, driven by the pressure difference between the blood and the capsule.

Embryonic development is defined as the period from week 1 to week 8 after fertilization, while fetal development is defined as the period from week 9 until birth.

The trophoblast is an outer layer of cells in the blastocyst that is essential for implantation into the uterine wall. It secretes human chorionic gonadotropin (hCG), which helps maintain the corpus luteum and prevents menstruation.

Sebaceous glands produce sebum, an oily substance that lubricates the hair and skin, preventing dryness and protecting against bacteria.

The epidermis is the outermost layer of skin, composed of stratified squamous epithelium. It undergoes continuous regeneration as new cells from the basal layer push older cells upwards, creating a protective barrier.

The epidermis undergoes complete regeneration approximately every 28 days. This means that the entire outer layer of skin is replaced about once a month.

The soles of the feet, constantly under pressure and abrasion, have a thicker stratum corneum than other areas of the body.

Helper T-cells, a type of T-cell, produce cytokines that stimulate other immune cells, including B-cells, to produce antibodies.

Active artificially acquired immunity is developed by the administration of a vaccine, which contains a weakened or inactive form of a pathogen. This allows the immune system to develop immunity without getting sick.

Inflammation causes swelling because blood vessels in the region become more permeable, allowing fluids to leak into tissue spaces. This leads to accumulation of white blood cells and tissue debris, contributing to swelling.

The ovum, after ovulation, enters the uterine tube, where it travels towards the uterus. This is the location where fertilization can occur if sperm is present.

Luteinizing hormone (LH) is thought to trigger ovulation. It causes the fully developed follicle to rupture, releasing the ovum into the uterine tube.

Testosterone is a hormone produced by the testes. It is responsible for the development of male secondary sexual characteristics, such as deeper voice, increased muscle mass, and growth of facial hair.

The zygote, after fertilization, undergoes rapid cell division and develops into a blastocyst, a hollow ball of cells consisting of an outer trophoblast and an inner cell mass. This is the stage when implantation occurs in the uterine lining.

The middle layer of the uterine tube wall is composed of smooth muscle, which contracts rhythmically to propel the ovum towards the uterus. This ensures that the ovum is transported to the uterus, where fertilization can occur.