Nervous System Overview

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Questions and Answers

What characterizes a comminuted fracture?

The bone breaks in more than two fragments (correct)

The bone only fractures superficially

The bone breaks into two fragments

The bone does not break at all

During which phase of fracture healing does hematoma formation occur?

Repair phase

Remodeling phase

Proliferative phase

Inflammatory phase (correct)

What is one of the key features of gout?

Inflammation in multiple joints simultaneously

Low levels of uric acid

Crystallization of uric acid causing tophi (correct)

Increased albumin levels in blood

What do myoblasts primarily contribute to in the body?

Muscle growth and regeneration Signup and view all the answers

Which of the following is NOT a symptom of osteoarthritis?

Systemic rash Signup and view all the answers

What distinguishes compact bone (cortical bone) from spongy bone?

It is denser and forms the outer layer of bones Signup and view all the answers

What is the significance of the epiphyseal plate in long bones?

It is responsible for bone lengthening during growth Signup and view all the answers

Which condition is characterized by acute decline in kidney function?

Acute Kidney Injury Signup and view all the answers

What role do osteoblasts play during the repair phase of fracture healing?

They synthesize collagen and matrix to form callus Signup and view all the answers

Which neuron type is primarily responsible for initiating movements and controlling muscle activity?

Motor neuron Signup and view all the answers

What is the main function of the occipital lobe in the brain?

Mapping the visual world Signup and view all the answers

Which type of cartilage is primarily responsible for reducing friction in joints?

Articular cartilage Signup and view all the answers

What characterizes the lower motor neurons compared to upper motor neurons?

They directly influence muscles. Signup and view all the answers

Which of the following best describes the function of the sympathetic nervous system?

Initiates the 'fight or flight' response. Signup and view all the answers

What is the primary risk factor for developing dementia?

Age Signup and view all the answers

Which structure provides a protective layer for the brain and spinal cord?

Meninges Signup and view all the answers

In which space is cerebrospinal fluid (CSF) primarily located?

Subarachnoid space Signup and view all the answers

What type of muscle is characterized as elongated and strap-like?

Fusiform muscle Signup and view all the answers

Which layer of the meninges is the tough and outermost layer that adheres to the skull?

Dura mater Signup and view all the answers

Which phase of fracture healing involves the transformation of hematoma into granulation tissue?

Repair phase Signup and view all the answers

What is a common symptom of gout that typically occurs at night?

Pain in the great toe Signup and view all the answers

Which of the following conditions involves the formation of tophi?

Gout Signup and view all the answers

Which structure in long bones is responsible for blood formation?

Medullary cavity Signup and view all the answers

What type of joint disorder is characterized by the loss of articular cartilage and bone spurs?

Osteoarthritis Signup and view all the answers

In the remodeling phase of fracture healing, what happens to unnecessary callus?

It is resorbed Signup and view all the answers

What pathological condition is associated with increased serum urate concentration?

Gout Signup and view all the answers

What is the primary role of myoblasts in muscle physiology?

Muscle growth and regeneration Signup and view all the answers

What is the function of the Haversian system in compact bone?

Facilitation of nutrient exchange Signup and view all the answers

What can trigger crystal deposition in the context of gout?

Low body temperature Signup and view all the answers

What is a primary function of the cerebellum in maintaining physical coordination?

Maintaining balance and posture Signup and view all the answers

Which type of neuron primarily transmits impulses from the central nervous system to muscles?

Efferent neurons Signup and view all the answers

Which statement accurately describes the function of the subdural space?

Located between the dura and arachnoid mater Signup and view all the answers

During which physiological response does the sympathetic nervous system primarily engage?

Preparing the body for 'fight or flight' Signup and view all the answers

What is one effect of aging on the musculoskeletal system?

Loss of bone tissue Signup and view all the answers

What type of joint is classified as amphiarthrosis?

Slightly movable joint Signup and view all the answers

What is the significance of the axon hillock in a neuron?

It is the site where action potentials initiate Signup and view all the answers

Which feature characterizes lower motor neurons compared to upper motor neurons?

Extend axons into the peripheral nervous system Signup and view all the answers

What is the primary action of the neurons in the afferent pathway?

Carrying information towards the CNS Signup and view all the answers

Which statement about articular cartilage is true?

Covers the ends of bones in joints Signup and view all the answers

What characterizes progressive dementia?

Gradual impairment of many cerebral functions Signup and view all the answers

Which of the following is NOT a symptom of damage to the occipital lobe?

Difficulty with balance Signup and view all the answers

In the context of cerebrospinal fluid (CSF), what is its main role?

Acts as a shock absorber and prevents brain tugging Signup and view all the answers

Which of these is a characteristic of fusiform muscles?

Elongated and strap-like Signup and view all the answers

What triggers tophi formation in gout?

Increased purine synthesis Signup and view all the answers

Which phase of fracture healing is characterized by the development of the callus?

Repair phase Signup and view all the answers

In osteoarthritis, which of the following is a common physical sign observed in finger joints?

Heberden's sign Signup and view all the answers

What marks the transition from the epiphyseal plate to the metaphysis in long bones?

Hormonal changes during puberty Signup and view all the answers

Which of the following factors is least likely to contribute to the crystal deposition in gout?

High serum cholesterol Signup and view all the answers

Which type of bone primarily makes up the outer structure of the skeletal system?

Compact bone Signup and view all the answers

Which statement about acute kidney injury is accurate?

It may lead to oliguria, or low urine production. Signup and view all the answers

What is the primary role of myoblasts following muscle injury?

To proliferate and differentiate into muscle fibers Signup and view all the answers

Which symptom is commonly associated with hyperuricemia?

Pain primarily in the great toe Signup and view all the answers

What initial response occurs after a bone fracture?

Inflammatory response with hematoma formation Signup and view all the answers

Which function is NOT associated with the frontal lobe?

Visual information mapping Signup and view all the answers

What is a characteristic of upper motor neurons?

Influence spinal reflexes Signup and view all the answers

Which statement is true regarding articular cartilage?

Covers the ends of bones in joints. Signup and view all the answers

What function does the cerebellum primarily serve?

Maintaining equilibrium and balance Signup and view all the answers

Which is NOT a feature of sympathetic nervous system stimulation?

Enhanced salivary secretion Signup and view all the answers

In which part of the nervous system do lower motor neurons primarily function?

Peripheral nervous system Signup and view all the answers

What characterizes the clinical presentation of dementia?

Progressive decline in multiple cerebral functions Signup and view all the answers

Which type of neuron transmits impulses towards the central nervous system?

Sensory neurons Signup and view all the answers

Which condition is primarily associated with aging changes in the musculoskeletal system?

Sarcopenia and decreased muscle mass Signup and view all the answers

Which of the following conditions is a risk factor for stroke?

Age over 55 Signup and view all the answers

What distinguishes the subarachnoid space?

It houses the cerebrospinal fluid. Signup and view all the answers

In what respect do fusiform muscles differ from pennate muscles?

Pennate muscles have a greater range of motion. Signup and view all the answers

Which structure is responsible for the production of cerebrospinal fluid?

Choroid plexuses Signup and view all the answers

Study Notes

Nervous System

CAD Diagnosis: Physical exam (listening to carotid artery with stethoscope for bruit), carotid ultrasound (sound waves to create images of carotid arteries and plaque), MRI, CT, and CT angiography (contrast dye to create images of carotid arteries).
Neurons: Fundamental unit of the nervous system, specialized cells for receiving, processing, and transmitting information throughout the body. Communicate with electrochemical signals.
Basic Structure:
Soma: Cell body (nucleus and organelles).
Dendrites: Finger-like extensions of the soma that receive signals from other neurons.
Axon: Carries nerve impulses away from the soma to other neurons, muscles, and glands; action potentials start at the axon hillock; terminal branches form synapses.
Multipolar neurons: Most common type, includes sensory neurons (transmit impulses from peripheral sensory receptors to the CNS), interneurons (decision-making neurons), and motor neurons (transmit impulses from the CNS to an effector organ).
Motor Neurons:
Transmit impulses from the CNS (brain and spinal cord) to an effector organ (muscles and glands).
Transmitted by the efferent pathway
Primary function to initiate and control movements.

Cerebellum

Maintains balance and posture.
Damage results in ipsilateral (same side) loss of equilibrium, balance, and motor coordination.
Conscious and unconscious muscle synergy.

Occipital Lobe

Maps the visual world.
Determines color properties, size, depth/distance.
Identifies visual stimuli.
Transmits visual information to other brain regions.

Frontal Lobe

Coordinates voluntary movements.
Assesses the future consequences of current actions.
Forms and retains long-term memories.
Responsible for language.
Involved in emotional expression and regulation, and personality development.

Meninges

Protective membrane surrounding the brain and spinal cord.
Dura mater: Tough outermost layer adhering to the skull.
Arachnoid mater: Thin, impermeable layer beneath dura mater.
Pia mater: Thin, vascular layer closely adhering to the brain and spinal cord.
Has three spaces, subdural, subarachnoid, and epidural.

CSF

Clear, colorless fluid similar to blood plasma, found in subarachnoid space.
Prevents brain from tugging on meninges, nerve roots and blood vessels.
Produced in choroid plexuses and reabsorbed in the arachnoid villi.
Exerts pressure within the brain and spinal cord.

Afferent Pathway

Ascending pathway carries information from sensory receptors to the spinal cord.
Sends impulses to the CNS via sensory neurons.

Efferent Pathway

Descending pathway carries information from the CNS to muscles and glands.
Impulses transmitted to effector organs via motor neurons.

Stroke Risk Factors

Age over 55
Family history
Race (African American, Hispanic, Native American)
Sex
Hypertension
High cholesterol
Heart disease
Diabetes
Smoking
Obesity
Poor diet
Sleep apnea
Drug usage

Stimulation of Sympathetic Nervous System

Decreases peristalsis.
Increases blood pressure, body temperature, and blood sugar level.
Regulates vasomotor tone.

Stimulation of Parasympathetic Nervous System

Promotes rest and tranquility ("rest and digest").
Reduces heart rate.
Enhances digestive processes.
Controls pupil constriction and tear secretion.
Increases salivary secretion.
Contracts the urinary bladder.

Dermatome

Area of skin on your body that relies on specific nerve connections on your spine, having a single sensory nerve fiber.

Dementia

Progressive failure of many cerebral functions causing impairment.
Onset is gradual.
Progressive dementia produces nerve cell degeneration and brain atrophy.
Age is the greatest risk factor.
Pathologies can include compression of brain tissue, genetic predisposition, CNS infections, brain trauma, neuron degeneration, and atherosclerosis of cerebral vessels.
Symptoms include impairment of intellectual function, memory, language, and alterations in behavior.

Musculoskeletal System

Articular Cartilage

Type of hyaline cartilage covering the ends of bones.
Reduction of friction in the joint.
Distribution of weight-bearing forces.
Has chondrocytes, intercellular matrix (collagen, polysaccharides, water).
No blood vessels, lymph nodes, or nerves (insensitive to pain).
Regenerates slowly.
Layered structure.

Surface Layer

Dense protective layer.
Middle layer: Interlaced fibers for weight bearing.
Perpendicular fibers resisting shear forces.
Calcified layer anchors structure to the bone.

Pennate Muscles

Broad, flat, and slightly fan-shaped.

Fusiform Muscles

Elongated, strap-shaped, running from one joint to another.

Sensory Receptors

Spindles: Mechanoreceptors responding to muscle stretching.
Responsible for muscle stretch response and maintaining muscle tone.

Oxygen Debt

Amount of oxygen needed to convert lactic acid to glucose and replenish ATP and phosphocreatine stores.

Effects of aging on the musculoskeletal system

Bones: Loss of bone tissue, stiffness, brittleness, decreased strength, lengthened bone remodeling cycle, slow mineralization, evidence of osteoporosis, increased bone resorption.
Joints: Degenerative change in cartilage (more rigid, fragile, stiff), increased risk of fraying, decreased range of motion.
Muscles: Apoptosis of cells, sarcopenia (loss of muscles), decreased muscle strength and bulk, reduced oxygen intake, altered basal metabolic rate, reduced lean body mass.

Amphiarthrosis

Slightly moveable joint, examples include intervertebral disks, ribs, and pelvis joints.

Comminuted Fracture

Bone fracture into more than two fragments.

Phases of healing in a fracture:

Inflammatory phase: lasts 3-4 days, bone tissue destruction triggers an inflammatory response, hematoma formation.
Repair phase: lasts several days.

Capillary Ingrowth, mononuclear cells, and fibroblasts

Transform hematoma into granulation tissue.
Osteoblasts synthesize collagen and matrix to form callus.

Remodeling Phase

Unnecessary callus is resorbed and trabeculae are formed.
The bone can withstand normal stress at the end of the process.

Gout

Metabolic disorder disrupting uric acid control in blood and body fluids.
High levels of uric acid crystallizing (tophi).
Low body temperature, decreased albumin or glycosaminoglycan levels, and trauma or changes in ion concentration or pH.

Pain in the great toe

Usually worse at night.
Increase in serum urate concentration (hyperuricemia)
Recurrent attacks of monoarticular arthritis involving one joint.
Deposits of tophi in and around the joints.
Renal disease involving glomerular, tubular, and interstitial tissues and blood vessels.
Formation of kidney stones.

Myoblasts

Primary cells for muscle growth and regeneration.
Aka satellite cells in an inactive state.
Become activated to form myoblasts and assist in muscle injury repair.

Osteoarthritis

Common age-related disorder of synovial joints.

Inflammatory Joint Disease

AKA degenerative joint disease.
Local areas of damage, loss of articular cartilage, bone spurs, and thickening of the joint capsule.
General signs; Pain, stiffness, enlargement of joint, tenderness, limited motion, and deformity.
Joint swelling (Heberden or Bouchard nodes)
Joint Effusion (exudate or blood entering the joint).

Compact Bone

AKA cortical bone
85% of the skeleton
Solid and strong
Haversian system: haversian canal, lamellae, lacunae, osteocytes, and canaliculi.

Long Bones

Diaphysis: Long shaft containing fat (yellow marrow) in the medullary cavity.
Metaphysis: Broad neck.
Epiphysis: End of long bone. Medullary cavity contributes to blood formation (red marrow). Epiphyseal plate (growth plate) present in kids.
Endosteum: Lines the medullary cavity.

Renal/Urinary System

Acute Kidney Injury: Sudden decline in kidney function with decreased glomerular filtration and accumulation of nitrogenous waste products in the blood (increasing CRT & BUN). Oliguric urine output <400 ml/day.
Tubular obstruction: Backleak of glomerular filtrate.

Chronic Kidney Disease

Progressive loss of renal function, associated with systemic diseases.
No symptoms until renal function drops below 25%.

ADH (Antidiuretic Hormone)

Controls final urine concentration.
Increases water permeability in the distal tubules and collecting ducts.
Stimulation by angiotensin II in RAAS (renin-angiotensin-aldosterone system).
Main function is to increase water reabsorption back into the bloodstream from the urine.

Urea

End-product of protein metabolism.
Major constituent of urine (50% excreted in urine, 50% recycled by kidneys).

Renal System Primary Functions (except)

Maintains stable internal environment for optimal cell and tissue metabolism.
Balances solute and water transport.
Excretes metabolic waste products.
Conserves nutrients (vitamins).
Regulates acids and bases.
Forms urine.
A nephron is the functional unit of the kidney.

Glomerular Hypertension

Increased pressure in the glomerular capillaries (caused by DM and HTN).
Leads to hyperfiltration (increased glomerular filtration rate).

Angiotensin II

Stimulates aldosterone secretion by adrenal cortex.
Increases sodium reabsorption and potassium secretion.
Increases water retention and blood volume/blood pressure.
Powerful vasconstrictor (constricts blood vessels).
Stimulates ADH secretion.

Loop of Henle

Enables kidneys to concentrate urine and conserve water.
Establishes a hyperosmotic state within the medullary interstitial fluid.
Countercurrent exchange system—fluid moves up and down parallel loops. Longer loops result in greater concentration gradients.

Protective Urinary Mechanisms (UTIs)

Washed out of the urethra during urination.
Lower pH and high osmolarity of urea.
Presence of Tamm-Horsfall protein (urothelium secretions) that is bactericidal.
Ureteroveical Junction closes to prevent reflux.
Women: mucus-secreting glands.
Men: longer urethra.

Effects of aging on renal function

Decrease in kidney size,
Decreased renal blood flow (RBF), and glomerular filtration rate (GFR)
Decreased number of nephrons.
Decreased tubular transport.

Ureters

30 cm long, smooth muscle.
Oblique passage through the bladder.
Peristaltic activity moves urine.
Micturition compresses ureter ends to prevent urine reflux.

Skin System

Candidiasis: Normally found on skin, GI tract, and vagina; can be widespread if environment supports it (warm, moist).
Function of fibroblasts: Secrete connective tissue matrix and collagen; help with structural integrity and tissue repair; during wound healing, they proliferate and synthesize new matrix components, helping with collagen regeneration.
Effects of aging on skin: Skin becomes thinner, drier, wrinkled, less elastic, changes in pigment (fewer melanocytes), decreased capillary loops, reduced melanocytes and Langerhans cells, decreased sebaceous, eccrine, apocrine glands (atrophy), compromised temperature regulation, decreased pressure receptors and free nerve endings, compromised protective function (increased infections and delayed wound healing).

Erysipelas

Acute superficial infection of upper dermis (superficial form of cellulitis).
Tx: Cold compresses, systemic antibiotics.

Folliculitis

Infection of hair follicles caused by staph.
Tx: Soap, water, topical antibiotics.

Furuncles

Inflammation of hair follicles (boils) caused by staph.
Develop from folliculitis.

Carbuncles

Collection of infected hair follicles (clump of boils).
Inflammation/development of abscesses.
Redness, painful swollen mass that drains through multiple openings.

Impetigo

Very common infection in children.
Superficial skin lesion caused by staph and strep.
Highly contagious crusty lesions.

Keloids

Elevated, rounded, firm, claw-like margins extending beyond the original site.
Hypertrophic scars, elevated erythematous fibrous lesions.
Excessive collagen formation and abnormal fibroblast activity.
Common in dark-skinned individuals.
Treated with corticosteroids, 5-FU, cryotherapy, radiotherapy, and surgical or laser procedures.

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Test your knowledge on the nervous system, including neurons and CAD diagnosis methods. This quiz covers the basic structure of neurons and their functions, as well as diagnostic techniques used in neurology such as ultrasound and MRI. Perfect for students and enthusiasts alike!