Physiology
Weak androgen like DHEA is secreted by _____________. * 1/1 A. Zona Glomerulosa Adrenal Cortex B. Zona Fasciculata Adrenal Cortex C. Zona Reticularis Adrenal Cortex D. Adrenal Medulla
Answer: C
a. NMJ b. Substantia nigra c. locus ceruleus of pons d. median raphe of brain stem e.Adrenal medulla 1. Dopamine 2. Epinephrine 3. Acetylcholine 4. serotonin 5. norepinephrine
Answer: 1. Dopamine: B 2. Epinephrine: E 3. Acetylcholine: A. 4. Serotonin: D. 5. Norepinephrine: C
contains the highest concentration of sodium
Nodes of Ranvier
What is the dominant form of CO2 in the blood? * 1/1 A. HCO3- B. CarbaminoHgB C. Freely-dissolved CO2 D. H+
aNSWER: A
Which neurotransmitter has the following characteristics: found as a gas, always an inhibitory NT, and can vasodilate arterioles? * 1/1 A. Nitrous Oxide B. Nitric Oxide C. Serotonin D. Dopamine
aNSWER: B. nitric oxide
Activates NMDA receptors
glutamate
conduction velocity is most dependent on
nerve diameter
F-actin is a component of the cellular cytoskeleton that: A. provides a structural component for cell movement. B. is defined as the "functional" form of actin in the cell. C. refers to the actin subunits that provide the molecular building blocks of the extended actin molecules found in the cell. D. provides the molecular architecture for cell to cell communication.
ANSWER: A • "Filamentous (F) actin provides a structural component for cell movement. • Globular (G) actin refers to the actin subunits that provide the molecular building blocks of the extended actin molecules found in the cell. • Microtubules provides the molecular architecture for cell to cell communication.
Which of the following is not correctly paired? A. Synaptic transmission: Antidromic conduction B. Molecular motors: Dynein and kinesin C. Fast axonal transport: ~400 mm/day D. Slow axonal transport: 0.5-10 mm/day E. Nerve growth factor: Retrograde transport
ANSWER: A • "In the natural situation, impulses pass in one direction only, ie, from synaptic junctions or receptors along axons to their termination. Such conduction is called orthodromic. Conduction in the opposite direction is called antidromic. Because synapses, unlike axons, permit conduction in one direction only, an antidromic impulse will fail to pass the first synapse they encounter and die out at that point."
A man falls into a deep sleep with one arm under his head. This arm is paralyzed when he awakens, but it tingles, and pain sensation in it is still intact. The reason for the loss of motor function without loss of pain sensation is A. A fibers are more susceptible to hypoxia than B fibers. B. A fibers are more sensitive to pressure than C fibers. C. C fibers are more sensitive to pressure than A fibers. D. Motor nerves are more affected by sleep than sensory nerves. E. Sensory nerves are nearer the bone than motor nerves and hence are less affected by pressure
ANSWER: B • "Conversely, pressure on a nerve can cause loss of conduction in large-diameter motor, touch, and pressure fibers while pain sensation remains relatively intact." Hypoxia: BAC Pressure: ABC Local anesthetics: CAB
The action potential of skeletal muscle: A. has a prolonged plateau phase. B. spreads inward to all parts of the muscle via the T tubules. C. causes the immediate uptake of Ca2+ into the lateral sacs of the sarcoplasmic reticulum. D. is longer than the action potential of cardiac muscle. E. is not essential for contraction
ANSWER: B • Action potential is essential for contraction which spreads inward to all parts of the muscle via the T- tubules; it triggers the release of Ca2+ from the terminal cisterns, the lateral sacs of the sarcoplasmic reticulum next to the T system; it is shorter than the action potential of cardiac muscle (which has prolonged plateau phase).
Which of the following statements about nerve growth factor is not true? A. It is made up of three polypeptide subunits. B. It is responsible for the growth and maintenance of adrenergic neurons in the basal forebrain and the striatum. C. It is necessary for the growth and development of the sympathetic nervous system. D. It is picked up by nerves from the organs they innervate. E. It can express both p75 NTR and Trk A receptors.
ANSWER: B • Nerve Growth Factor is made up of three polypeptide subunits. It can be express both p75 NTR and Trk A receptors. It is necessary for the growth and development of the sympathetic nervous system; and cholinergic neurons in the basal forebrain and the striatum. It is picked up by nerves from the organs they innervate.
The cross-bridges of the sarcomere in skeletal muscle are made up of A. actin. B. myosin. C. troponin. D. tropomyosin. E. myelin.
ANSWER: B • Tropomyosin: acting as a "relaxing protein" at rest by covering up the sites where myosin binds to actin. • Myosin: sliding on actin to produce shortening/ cross-bridging. • Actin: binding to myosin head during contraction. • Troponin T binds the troponin components to tropomyosin; • Troponin I inhibit the interaction of myosin with actin; and • Troponin C contains the binding sites for the Ca2+ that helps to initiate contraction. Myelin covers the nerve fibers
A 20-year-old female student awakens one morning with severe pain and blurry vision in her left eye; the symptoms abate over several days. About 6 months later, on a morning after playing volleyball with friends, she notices weakness but not pain in her right leg; the symptoms intensify while taking a hot shower. Which of the following is most likely to be the case? A. The two episodes described are not likely to be related. B. She may have primary-progressive multiple sclerosis. C. She may have relapsing-remitting multiple sclerosis. D. She may have a lumbar disk rupture. E. She may have Guillain-Barre syndrome
ANSWER: C Relapsing-Remitting MS: transient episodes lasting weeks or months that recur Primary-progressive MS: no periods of remission CLinical features: 1. optic neuritis 2. Paraparesis (weakness of LE) 3. high temperature • "Typical physiological deficits of multiple sclerosis range from muscle weakness, fatigue, diminished coordination, slurred speech, blurred or hazy vision, bladder dysfunction, and sensory disturbances. Symptoms are often exasperated by increased body temperature or ambient temperature." • "In the most common form, transient episodes appear suddenly, last a few weeks or months, and then gradually disappear. Subsequent episodes can appear years later, and eventually full recovery does not occur. Others have a progressive form of the disease in which there are no periods of remission."
Gap junctions A. are absent in cardiac muscle. B. are present but of little functional importance in cardiac muscle. C. are present and provide the pathway for rapid spread of excitation from one cardiac muscle fiber to another. D. are absent in smooth muscle. E. connect the sarcotubular system to individual skeletal muscle cell
ANSWER: C • "Gap junctions are present in cardiac muscles and provide the pathway for rapid spread of excitation from one cardiac muscle fiber to another. It is also present in smooth muscle, which is responsible for its unitary movement; on the other hand, it is absent in skeletal muscle cells
Which of the following ionic changes is correctly matched with a component of the action potential? A. Opening of voltage-gated K+ channels: After-hyperpolarization B. A decrease in extracellular Ca2+: Repolarization C. Opening of voltage-gated Na+ channels: Depolarization D. Rapid closure of voltage-gated Na+ channels: Resting membrane potential E. Rapid closure of voltage-gated K+ channels: Relative refractory period
ANSWER: C • Opening of voltage-gated Na+ channels: Depolarization • Opening of voltage-gated K+ channels: Repolarization • A decrease in extracellular Ca2+: increased excitability → affects Resting Membrane Potential • Rapid closure of voltage-gated Na+ channels: Inactivated sate → Relative Refractory Period • Slow closure of voltage-gated K+ channels: Afterhyperpolarization
The functions of tropomyosin in skeletal muscle include: A. sliding on actin to produce shortening. B. releasing Ca2+ after initiation of contraction. C. binding to myosin during contraction. D. acting as a "relaxing protein" at rest by covering up the sites where myosin binds to actin. E. generating ATP, which it passes to the contractile mechanism
ANSWER: D • Tropomyosin: acting as a "relaxing protein" at rest by covering up the sites where myosin binds to actin. • Myosin: sliding on actin to produce shortening. • Sarcoplasmic reticulum: releasing Ca2+ after initiation of contraction. Actin: binding to myosin during contraction. •Phosphocreatine: generating ATP, which it passes to the contractile mechanism.
Second messengers: A. are substances that interact with first messengers outside cells. B. are substances that bind to first messengers in the cell membrane. C. are hormones secreted by cells in response to stimulation by another hormone. D. mediate the intracellular responses to many different hormones and neurotransmitters. E. are not formed in the brain
ANSWER: D. Second messengers bring about many short-term changes in cell function by altering enzyme function, triggering exocytosis, and also can lead to the alteration of transcription of various genes.
Primary erythromelalgia, which may be due to a peripheral nerve sodium channelopathy, was diagnosed in a 13-year-old girl who was experiencing frequent episodes of red, painful, warm extremities. Which part of a neuron has the highest concentration of Na+ channels per square micrometer of cell membrane? A. dendrites B. cell body near dendrites C. initial segment D. axonal membrane under myelin E. node of Ranvier
ANSWER: E • "The number of Na+ channels per square micrometer of membrane in myelinated mammalian neurons has been estimated to be: Cell body: 50-75 Initial segment: 350-500 Surface of myelin: less than 25 Nodes of Ranvier: 2000-12,000 Axon terminals: 20-75
When LDL enters cells by receptor-mediated endocytosis, which of the following does not occur? A. ↓ in the formation of cholesterol from mevalonic acid B. ↑ in the intracellular concentration of cholesteryl esters C. ↑ in the transfer of cholesterol from the cell to HDL D. ↓ in the rate of synthesis of LDL receptors E. ↓ in the cholesterol in endosomes
ANswer: E. • When LDL enters cells by receptor-mediated endocytosis, there will be: 1. Decrease in the formation of cholesterol and in the rate of synthesis of LDL receptors. 2. Increase in the intracellular concentration of cholesteryl esters, transfer of cholesterol from the cell to HDL, and amount of cholesterol in endosomes
a 56 year old woman with severe muscle weakness is hospitalized. The only abnormality in her laboratory vaues is an elevated serum K concentrations, The elevated serum K causes muscle weakness because a. RMP is hyperpolarized b. K+ equilibrium potential is hyperpolarized c. K+ channels are closed by depolarization d.K+ channels are opened by depolarization e. Na channels are closed by depolarization
Answer: A
hat is the effect of PTH on Plasma Calcium and Plasma Phosphate? * 1/1 A. Increased plasma calcium, decreased plasma phosphate B. Increased plasma calcium, Increased plasma phosphate C. Decreased plasma calcium, increased plasma phosphate D. Decreased plasma calcium, decreased plasma phosphate
Answer: A
The electrogenic Na+, K+ ATPase plays a critical role in cellular physiology A. by using the energy in ATP to extrude 3 Na+ out of the cell in exchange for taking two K+ into the cell. B. by using the energy in ATP to extrude 3 K+ out of the cell in exchange for taking two Na+ into the cell. C. by using the energy in moving Na+ into the cell or K+ outside the cell to make ATP. D. by using the energy in moving Na+ outside of the cell or K+ inside the cell to make ATP.
Answer: A Na+, K+ ATPase catalyzes the hydrolysis of ATP to adenosine diphosphate (ADP) and uses the energy to extrude three Na+ from the cell and take two K+ into the cell for each molecule of ATP hydrolyzed." • It is an electrogenic pump which does not produce new ATP.
Acts as vasoconstrictor of the afferent arteriole? * 1/1 A. Adenosine B. Nitric Oxide C. Aldosterone D. All of the above
Answer: A Adenosine- cAMP
Solutions A and B are separated by a membrane that is permeable to urea. Solution A is 10 mM urea and solution B is 5mM. If the concentration of urea in solution A is doubled, the flux of urea across the membrane will a. Double b. Triple c. be unchanged d. decrease to 1/2 e. decrease to 1/3
Answer: A. Reflection coefficient of urea = 0 (complete penetration)
solutions A and B are separated by a semipermeable membrane that is permeable to K+ but not to Cl-. Solution A is 100 mM KCl and solution B is 1mM KCl. Which of the following statements about solutions A and solutions B is true? A. K+ ions will diffuse from solution A to solution B until the K+ of both solutions is 50.5mM B. K ions will diffuse from solution B to solution A until the K of both solutions is 50.5 mM C. KCl will diffuse from solution A to solution B until the KCl of both solutions is 50.5 D. K+ will diffuse from solutions A to Solution B until the membrane potential develops with solution A negative with respect to solution B E. K+ will diffuse from solution A to solution B until a membrane potential develops with solution A positive with respect to solution B
Answer: A. Nernst potential (Equilibrium potential) - diffusion potential that exactly balances the tendency for diffusion caused by concentration difference. equilibrium potential in nerve and muscle
What is the approximate number of neurons? * 0/1 A. 100 billion B. 1 trillion C. 30 trillion D. 68 trillion
Answer: A. 100 Billion
trigger REM sleep A. Acetylcholine B. Glycine C. GABA D. Serotonin
Answer: A. Acetylcholine
Responsible for interhemispheric communication: __________. * 1/1 A. Corpus Callosum B. Thalamus C. Hippocampus D. Cerebral cortex
Answer: A. Corpus callosum
depolarizes postsynaptic cell, brings closer to threshold A. Excitatory Post synaptic Potentials B. Inhibitory Post synaptic potentials C. Excitatory Pre synaptic Potentials D. Inhibitory Pre synaptic potentials
Answer: A. EPSP (clue: Depolarizes: Na influx) B. IPSP: Hyperpolarizes; Cl influx
Which muscle fiber is involved in muscle endurance? * 1/1 A. Type I muscle fiber, extrafusal B. Type II muscle fiber, extrafusal C. Type I muscle fiber, intrafusal D. Type II muscle fiber, intrafusal
Answer: A. Type I, extrafusal
Which of the following statements about nerve growth factor is NOT true? A. It is made up of three polypeptide subunits B. It facilitates the process of apoptosis C. It is necessary for the growth and development of the sympathetic nervous system D. It is picked up by nerves from the organs they innervate E. It is present in the brain
Answer: B "Nerve Growth Factor is made up of three polypeptide subunits. It is necessary for the growth and development of the sympathetic nervous system; and cholinergic neurons in the basal forebrain and the striatum. There is evidence that the maintenance of neurons by NGF is due to a reduction in apoptosis. It is picked up by nerves from the organs they innervate."
The Golgi complex A. is an organelle that participates in the breakdown of proteins and lipids. B. is an organelle that participates in posttranslational processing of proteins. C. is an organelle that participates in energy production. D. is an organelle that participates in transcription and translation. E. is a subcellular compartment that stores proteins for trafficking to the nucleus
Answer: B. A. Lysosomes C. Mitochondria D. Nucleus E. RER
Transcription refers to: A. the process where an mRNA is used as a template for protein production. B. the process where a DNA sequence is copied into RNA for the purpose of gene expression. C. the process where DNA wraps around histones to form a nucleosome. D. the process of replication of DNA prior to cell division
Answer: B. Transcription is the process where a DNA sequence is copied into RNA for the purpose of gene expression. • Translation is the process where an mRNA is used as a template for protein production. • Synthesis is the process of replication of DNA prior to cell division. Ganong. Review of Medical Physiology 23rd ed. Ch
Gap junctions are intercellular connections that A. primarily serve to keep cells separated and allow for transport across a tissue barrier. B. serve as a regulated cytoplasmic bridge for sharing of small molecules between cells. C. serve as a barrier to prevent protein movement within the cellular membrane. D. are cellular components for constitutive exocytosis that occurs between adjacent cells
Answer: B. (clue: Sharing) A. Tight junction (zonula adherens); clue: Barrier C. Tight junction D. paracellular transport (tight jxn) Tight junctions provide intercellular connections that link cells into a regulated tissue barrier, it also provides barrier to movement of proteins in the cell membrane and thus, are important to cellular polarization. • Gap junctions provide contacts between cells that allow for direct passage of small molecules between two cells. • Desmosomes and adherens junctions are specialized structures that hold cells together. • Hemidesmosomes and focal adhesions attach cells to their basal lamina
The membrane potential of a particular cell is at the K+ equilibrium. The intracellular concentration for K+ is at 150 mmol/L and the extracellular concentration for K+ is at 5.5 mmol/L. What is the resting potential? A. -70 mV B. -90 mV C. +70 mV D. +90 mV
Answer: B. -90 mV Equilibrium potential: K: -90 mV (-88 mV) Cl: -70 mV Na: +65 mV RMP of action potential: -70 mV
Urge to defecate occurs once the rectum is ______ filled. * 1/1 a. 10% b. 25% c. 50% d. 75%
Answer: B. 25%
The distance from between one stimulating electrode to recording electrode is 4.5 cm. When the axon is stimulated, the latent period is 1.5 ms. What is the conduction velocity of the axon? A. 15 m/s B. 30 m/s C. 40 m/s D. 67.5 m/s E. This cannot be determined from the information given.
Answer: B. 30 m/s If the duration of the latent period and the distance between the stimulating and recording electrodes are known, axonal conduction velocity can be calculated. • Convert the units: 4.5cm = 0.045m; 1.5ms = 0.0015s • Conduction Velocity = Distance/Latent period • Conduction Velocity = 0.045m/0.0015s = 30 m/s
Act as "primer pumps" of the heart: _____________. * 1/1 A. SA Node B. Atria C. Ventricles D. SVC and IVC
Answer: B. Atria
which of the following will double the permeability of a solute in a lipid bilayer? a. Doublig the molecular radius of the solute b. Doubling the oil/water partition coefficient of the solute c. Doubling the thickness of the bilayer d. Doubling the concentration difference of the solute across the bilayer
Answer: B. Partition coefficient AKA. Distribution coefficient - movement of drug molecules from one phase (aqueous/water) to another phase (organic/ oil) and vice versa
Fill in the blanks: Glycogen is a storage form of glucose. _______ refers to the process of making glycogen and _______ refers to the process of breakdown of glycogen. A.glycogenolysis, glycogenesis B.glycolysis, glycogenolysis C.glycogenesis, glycogenolysis D.glycogenolysis, glycolysis
Answer: C
Which of the following is true: I. Normal Filtration Fraction (FF) is 20%. II. FF = GFR/RPF III. Highest FF is seen in efferent arteriolar constriction. 1/1 A. Statements I and II are correct B. Statements II and III are correct C. Statements I, II and III are correct Statements I and III are correct
Answer: C.
G-protein-coupled receptors: A. are intracellular membrane proteins that help regulate movement within the cell. B. are plasma membrane proteins that couple the extracellular binding of primary signaling molecules to exocytosis. C. are plasma membrane proteins that couple the extracellular binding of primary signaling molecules to the activation of heterotrimeric Gproteins. D. are intracellular proteins that couple the binding of primary messenger molecules with transcription
Answer: C. G-protein-coupled receptors are plasma membrane proteins that couple the extracellular binding of primary signaling molecules to the activation of heterotrimeric G-proteins."
The contractile response in skeletal muscle A. starts after the action potential is over. B. does not last as long as the action potential. C. produces more tension when the muscle contracts isometrically than when the muscle contracts isotonically. D. produces more work when the muscle contracts isometrically than when the muscle contracts isotonically. E. decreases in magnitude with repeated stimulation.
Answer: C. ISOMETRIC: TENSION ISOTONIC: WORK Muscle fiber does not have a refractory period, repeated stimulation before relaxation produces additional activation of the contractile elements, or summation of contractions. • Note that because work is the product of force times distance, isotonic contractions do work, whereas isometric contractions do not. • When the muscle fiber contracts isometrically, the tension developed is proportional to the number of cross-bridges between the actin and the myosin molecules • Contraction starts before the action potential is over and last longer as the action potential.
Endocytosis A. includes phagocytosis and pinocytosis, but not clathrin mediated or caveolae-dependent uptake of extracellular contents. B. refers to the merging of an intracellular vesicle with the plasma membrane to deliver intracellular contents to the extracellular milieu. C. refers to the invagination of the plasma membrane to uptake extracellular contents into the cell. D. refers to vesicular trafficking between Golgi stacks.
Answer: C. (clue: invagination) A.include phagocytosis, pinocytosis, clathrine mediated or caveolae-dependent uptake B: exocytosis D. Exocytosis
The difference in concentration of H+ in a solution of pH 2.0 compared with one of pH 7.0 is: A. 5-fold B. 1/5 as much C. 10 ^5-fold D. 10 ^-5 as much
Answer: C. 10^ 5 fold For each pH unit less than 7.0, the [H+] is increased tenfold (101); for each pH unit above 7.0, it is decreased tenfold (10-1)." • The difference in pH between 2.0 and 7.0 is 5, therefore an increase of 105 is expected
which of the following is an inhibitory neurotransmitter in the CNS? a. Norepinephrine b. Glutamate c. GABA d. Serotonin E. Histamine
Answer: C. GLUTAMATE (brain) Glycine (SPinal cord)mi8
Which antibody is involved in the primary response? * 1/1 A. IgG B. IgA C. IgM D. IgE E. IgD
Answer: C. IgM
Which part of a neuron has the highest concentration of Na+ channels per square millimeter of cell membrane? A. dendrites B. cell body near dendrites C. initial segment D. axonal membrane under myelin E. none of the above
Answer: C. Initial segment 1. Nodes of Ranvier: 2000-12,000 2. Initial segment: 350-500 3. Cell body: 50-75 4. Axon terminalis: 20-75 5. surface of myelin: <25
Which of the following statements about glia is true? A. Microglia arise from macrophages outside of the nervous system and are physiologically and embryologically similar to other neural cell types. B. Glia do not undergo proliferation. C. Protoplasmic astrocytes produce substances that are tropic to neurons to help maintain the appropriate concentration of ions and neurotransmitters by taking up K+ and the neurotransmitters glutamate and GABA. D. Oligodendrocytes and Schwann cells are involved in myelin formation around axons in the peripheral and central nervous systems, respectively. E. Macroglia are scavenger cells that resemble tissue macrophages and remove debris resulting from injury, infection, and disease
Answer: C. Protoplasmic astrocytes Protoplasmic astrocytes produce substances that are tropic to neurons to help maintain the appropriate concentration of ions and neurotransmitters by taking up K+ and the neurotransmitters glutamate and GABA." • "Microglia arise from macrophages outside of the nervous system and are physiologically and embryologically unrelated to other neural cell types; they are scavenger cells that resemble tissue macrophages and remove debris resulting from injury, infection, and disease." • "Oligodendrocytes and Schwann cells are involved in myelin formation around axons in the central and peripheral nervous systems, respectively. Glia undergo proliferation." Fibrous astrocytes: astrocytes in the white matter Astrocytes: Macroglia that send processes that envelop synapses and the surface of nerve cells and helps form the BBB
Site of gas exchange: _________. * 1/1 A. Arteries B. Arterioles C. Capillaries D. Veins E. Lymphatics
Answer: C. capillaries A. stressed pressure B. Resistance D. Compliance
The primary structure of a protein refers to: A. the twist, folds, or twist and folds of the amino acid sequence into stabilized structures within the protein (i.e. α-helices and β-sheets). B. the arrangement of subunits to form a functional structure. C. the amino acid sequence of the protein. D. the arrangement of twisted chains and folds within a protein into a stable structure.
Answer: C: Amino acid Primary structure is the amino acid sequence of the protein. • Secondary structure is the twist, folds, or twist and folds of the amino acid sequence into stabilized structures within the protein (i.e. α-helices and β-sheets). • Tertiary structure is the arrangement of twisted chains and folds within a protein into a stable structure. • Quaternary structure is the arrangement of subunits to form a functional structure.
Edema can be caused by which of the following? * 1/1 A. Increased capillary hydrostatic pressure B. Decreased capillary oncotic pressure C. Increased filtration coefficient D. All of the above
Answer: D.
SARS-Cov-2 binds to which of the following? * 1/1 A. ACE B. ACE2 C. ACE Receptor D. ACE2 Receptor
Answer: D.
Which of the following is expected due to high altitude? * 1/1 A. Initial respiratory alkalosis that eventually declines due to renal compensation B. Increased RBC production and blood vessel formation C. Shift to the right of the O2-HgB dissociation curve D. All of the above
Answer: D.
Cell membranes: A. contain relatively few protein molecules. B. contain many carbohydrate molecules. C. are freely permeable to electrolytes but not to proteins. D. have variable protein and lipid contents depending on their location in the cell. E. have a stable composition throughout the life of the cell
Answer: D. A: Many proteins B. Many Phospholipids C. Semipermeable E. Variable composition
Identify: part of the Enteric nervous system, and responsible for contraction of the muscularis mucosa: _________. * 0/1 A. Parasympathetic NS B. Sympathetic NS C. Meissner Plexus D. Auerbach Plexus
Answer: D. Auerbach plexus
Choose the best answer: I. Simple diffusion is slower than Facilitated Diffusion at low solute concentration but faster at high solute concentration II. Simple diffusion is carrier-mediated, Facilitated Diffusion is non-carrier-mediated III. Simple diffusion and Facilitate Diffusion are passively transported * A. Statements I and II are correct B. Statements II and III are correct C. Statements I, II and III are correct D. tatements I and III are correct
Answer: D. I and III II. SD: Noncarrier mediated; FD: carrier-mediated
The major lipoprotein source of the cholesterol used in cells is: A. chylomicrons B. intermediate-density lipoproteins (IDL) C. albumin-bound free fatty acids D. low-density lipoproteins (LDL) E. high-density lipoproteins (HDL)
Answer: D. LDL • "Low-density lipoproteins (LDL) is the major lipoprotein source of the cholesterol used in cells. Chylomicrons is the transport system for ingested exogenous lipids (exogenous pathway). • Intermediate-density lipoproteins (IDL) give up phospholipids and, through the action of the plasma enzyme lecithin-cholesterol acyltransferase (LCAT), pick up cholesteryl esters formed from cholesterol in the HDL. • High-density lipoproteins (HDL), also transports triglycerides and cholesterol throughout the body."
In which part of the Menstrual Cycle is LH at its highest? * 1/1 A. Menses B. Follicular Phase C. Luteal Phase D. Ovulation
Answer: D. Ovulation
What is the longest phase of the cardiac cycle? * 1/1 A. Reduced Ventricular ejection B. Isovolumic Relaxation C. Rapid Ventricular Filling D. Reduced Ventricular Filling
Answer: D. Reduced ventricular filling Cardiac cycle: AIRSIRS
What maintains oxygenation of the blood when you hold your breath? * 1/1 A. IRV B. TV C. ERV D. RV
Answer: D. Residual volume
A 45-year-old woman who works in an office had been experiencing tingling in her index and middle fingers and thumb of her right hand. Recently, her wrist and hand had become weak. Her physician ordered a nerve conduction test to evaluate her for carpal tunnel syndrome. Which one of the following nerves has the slowest conduction velocity? A. Aα fibers B. Aβ fibers C. Aγ fibers D. B fibers E. C fibers
Answer: E • "In general, the greater the diameter of a given nerve fiber, the greater its speed of conduction." • In decreasing order of diameter and speed: • Aα fibers > Aβ fibers > Aγ fibers > B fibers > C fibers Speed (slowest-fastest): CAB Local anesthetics: CAB Pressure: ABC Hypoxia: BAC
Which of the following produces the most high-energy phosphate compounds? A. Aerobic metabolism of 1 mol of glucose B. Anaerobic metabolism of 1 mol of glucose C. Metabolism of 1 mol of galactose D. Metabolism of 1 mol of amino acid E. Metabolism of 1 mol of long-chain fatty acid
Answer: E. long Fatty acid "Catabolism of 1 mol of a six-carbon fatty acid through the citric acid cycle to CO2 and H2O generates 44 mol of ATP, compared with the 38 mol generated by catabolism of 1 mol of the six-carbon carbohydrate glucose.
Macrophages secrete which cytokines? * 1/1 A. IL-1, IL-6, IL-8 B. TNF-alpha C. TGF- beta D. All of the above
Answer:D
causes reduction of potassium leak out of the cells
Hyperpolarizing the membrane potential
autoimmune disease that attacks the myelin resulting in demyelination
Multiple sclerosis clinical features: Paraparesis (weakness of LE) paresthesia optic neuritis exacerbated by increased temperature
Relaxes Lower Esophageal Sphincter (LES), Orad Stomach, Pyloric Sphincter, Ileocecal Valve: __________. * 1/1 a. VIP b. GIP c. GLP-1 d. glucagon
answer: A.
Which of the following is true? I. Peripheral chemoreceptors are located in the aortic arch and carotid sinus while central chemoreceptors are located in the medulla. II. Peripheral chemoreceptors respond best to hypoxemia, while central chemoreceptors respond to CSF H+. III. Chemoreceptors can trigger increase in the respiratory rate. * 1/1 A. Statements I and II are correct B. Statements II and III are correct C. Statements I, II and III are correct D. Statements I and III are correct
answer: B. I. Aortic body and carotid body
degeneration od dopaminergic neurons has been implicated in: a. Schizophrenia b. Parkinsons disease c. myasthenia gravis d. curare poisoning
answer: B. Parkinsons disease
Patient develops fever after halothane is given. Treatment? * 1/1 A. Paracetamol B. Steroids C. Dantrolene D. ASA
answer: C. dantrolene Hyperthermia - halothane, succinylcholine,stress, exercise
