Physiology I Flashcards by Tom Porter

What major cations are most abundant in the extracellular fluid?

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What major cations are most abundant in the intracellular fluid?

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What major anions are most abundant in the extracellular fluid?

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What major anions are most abundant in the intracellular fluid?

PO4, organic anions

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Which of the following would have to be a transmembrane protein?

A. A receptor protein
B. A protein binding to the cytoskeleton
C. A channel protein
D. A phosphorylase

C. a channel protein

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Which of the following organelles is directly associated with the synthesis of proteins for secretion?

A. mitochondria
B. golgi apparatus
C. nucleus
D. rough endoplasmic reticulum
E. smooth endoplasmic reticulum

D. rough endoplasmic reticulum

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Pits coated with which of the following are often associated with endocytosis?

A. Clathrin
B. COPI
C. COPII
D. Coatamers
E. Vinculin

A. Clathrin

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Which of the following processes does not require the presence of mitochondria?

A. Oxidative Phosphorylation
B. Production of carbon dioxide and whater
C. Breakdown of glucose to pyruvic acid
D. Electron transfer between cytochromes
E. Utilization of oxygen as a final electron receptor

C. Breakdown of glucose to pyruvic acid

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Which of the following transport mechanisms requires energy other than kinetic energy?

A. osmosis
B. diffusion
C. active transport
D. facilitated diffusion

C. active transport

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Of the following ions, which is most concentrated in the extracellular environments?

A. sodium
B. potassium
C. chloride
D. calcium

A. sodium

potassium is the most concentrated outside

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The sodium-potassium pump is an example of which of the following kinds of transport?

A. diffusion
B. primary active transport
C. secondary active transport
D. facilitated diffusion

B. primary active transport

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The sodium-glucose pump is an example of which of the following kinds of transport?

A. diffusion
B. primary active transport
C. secondary active transport
D. facilitated diffusion

C. secondary active transport

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The sodium-calcium pump is an example of which of the following kinds of transport?

A. diffusion
B. primary active transport
C. secondary active transport
D. facilitated diffusion

C. secondary active transport

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Glucose transporters (GLUT transporters) employ which of the following kinds of transport?

A. diffusion
B. primary active transport
C. secondary active transport
D. facilitated diffusion

D. facilitated diffusion

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Which of the following mechanisms would most likely be used to move water from an extracellular environment across an epithelial cell layer into an extracellular environment on the opposite side of the epithelial layer?

A. sodium channels and sodium ATPase pumps
B. calcium channels and sodium ATPase pumps
C. calcium channels and calcium ATPase pumps
D. sodium channels and sodium ATPase pumps

A. sodium channels and sodium ATPase pumps

water follows the increase in sodium concentration

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The action potential for both ventricular cardiomyocytes and a Purkinje fiber exhibit a plateau phase (phases 1 and 2). Conductance of which of the following ions is responsible for phase 0?

A. calcium ions
B. potassium ions
C. sodium ions
D. both potassium and calcium ions

C. sodium ions

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Which of the following characteristics would be true of cardiac muscle cells but not skeletal muscle fibers?

A. cells have the sarcomeric banded pattern
B. cells utilize T-tubules
C. cells are mononucleated
D. cells utilize ryanodine channels

C. cells are mononucleated

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The resting potential of -85 mv is characteristic of which of the following phases of the cardiac fast action potentials?

A. stage 1
B. stage 2
C. stage 3
D. stage 4

D. stage 4

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The sodium-calcium exchanger in the sarcolemma of the cardiac muscle cell is an example of which of the following mechanisms?

A. primary active transport involving an antiporter
B. primary active transport involving a symporter
C. secondary active transport involving a symporter
D. secondary active transport involving an antiporter

D. secondary active transport involving an antiporter

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Left ventricular isovolumic contraction occurs immediately following which of the following events?

A. closure of aortic valve
B. opening of aortic valve
C. closure of AV valve
D. opening of AV valve

C. closure of AV valve

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Which of the following statements is true for the period of rapid ejection?

A. it occurs when the left ventricular pressure is above 80 mm Hg
B. the semilunar valves are closed during this phase
C. it occurs during the last two-thirds of ejection
D. it results in the ejection of about 90% of the total volume of blood

A. it occurs when the left ventricular pressure is above 80 mm Hg

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Immediately prior to the ventricular isovolumic contraction, there is a slight but marked elevation in atrial pressure. Which of the following is responsible for this elevated pressure?

A. closure of the AV valve
B. opening of the AV valve
C. atrial contraction
D. diastasis
E. opening of the semilunar valve

C. atrial contraction

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The Frank-Sterling law is based on which of the following principles?

A. the greater the stretching of cardiac muscle, the greater the force of contraction
B. the more calcium returned to the sarcoplasmic reticulum, the greater the force of contraction
C. the amount of blood received by each tissue is directly related to the immediate needs of that tissue
D. the faster the heart rate, the more likely that the period of diastasis will be eliminated

A. the greater the stretching of the cardiac muscle, the greater the force of the contraction

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Stroke volume output can be increased by which of the following mechanisms?

A. Decreasing EDV
B. Increasing EDV
C. Increasing ESV
D. By decreasing EDV and increasing ESV

B. increasing EDV

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Excess potassium in the extracellular fluid would have which of the following effects on heart activity? A. heart will become dilated B. heart rate will increase C. heart will go toward spastic contraction D. heart action potential will increase

A. heart will become dilated

In a typical ECG, which of the following waves occurs at the beginning of the contraction of the atria? ``` A. T B. R C. S D. P E. Q ```

D. P

If the end-diastolic volume is 110 ml and the end-systolic volume is 30 ml, the stroke volume is...? ``` A. 140 ml B. 80 ml C. 70 ml D. 40 ml E. 10 ml ```

B. 80 ml SV = end diastolic - end systolic

If the end diastolic volume is 120 ml, and the end-systolic volume is 50 ml, what is the approximate value of the ejection fraction? A. 42% B. 60% C. 214% D. 240%

B. 60% SV = end diastolic - end systolic EF = SV/end diastolic

Isovolumic contraction of the ventricles occurs: A. at the beginning of systole B. at the end of systole C. at the beginning of diastole D. after the opening of the semilunar valves

A. at the beginning of systole

Neostigmine can be used to alleviate some of the effects of myasthenia gravis, an autoimmune disease in which antibodies attack acetylcholine receptors. Which of the following best represents neostigmine's effects? A. neostigmine initiates the opening of more sodium channels creating stronger end plate potentials B. neostigmine binds to the antibodies and allows more acetylcholine receptors to participate in creating a stronger end plate potential C. neostigmine inactivates acetylcholinesterase, allowing more acetylcholine molecules to bind to receptors and create stronger end plate potentials D. neostigmine binds to voltage-gated sodium channels and initiates a stronger action potential

C. neostigmine inactivates acetylcholinesterase, allowing more acetylcholine molecules to bind to receptors and create stronger end plate potentials

Which of the following are anchored to the presynaptic membrane and are associated with synaptic vesicles to which they are tethered by short filaments? A. synaptic vesicles B. calcium channels C. dense bars D. dihydropyridine channels

C. dense bars

In order for an acetylcholine-gated ion channel to open, how many Ach molecules are necessary to attach to its alpha subunit? A. one B. two C. three D. four

B. two

Which of the following represents the first thing that happens after Ach binds to the ligand-gated channels on the sarcolemma? A. an action potential is created on the sarcolemma B. dihydropyridine channels allow entry of calcium ions C. an end-plate potential is created on the muscle fiber D. ryanodingaling channels allow calcium to escape into the myoplasm

C. an end-plate potential is created on the muscle fiber

The vesicles for acetylcholine are transported to the axon terminal from where? A. rough ER B. smooth ER C. the axon terminal membrane D. golgi

D. golgi

Which of the following can be used to inactivate acetylcholinesterase? A. methacholine B. neostigmine C. physostigmine D. carbachol

B. neostigmine

Which of the following represents an example of an eccentric contraction? A. the triceps muscle during the throwing of a ball B. the triceps muscle while raising the body from the floor during a push-up C. the triceps muscle while lowering the body to the floor during a push-up D. the biceps muscle while raising the body during a pull-up

C. the triceps muscle while lowering the body to the floor during a push-up

Ducks, geese, and many other species of birds may make long migratory trips during which they fly for long periods of time. Which of the following characteristics would be expected of their flight muscles (pectoralis complex)? A. their flight muscle fibers would have relatively small numbers of mitochondria B. their flight muscle fibers would have relatively small amounts of myoglobin C. their flight muscle fibers would have small concentrations of ATPase D. their flight muscles would have a more extensive sarcoplasmic reticulum

C. their flight muscle fibers would have small concentrations of ATPase

During skeletal muscle contraction, myosin heads go through repeated cycles in which they bind to actin, swivel to produce the power stroke, release from actin, and recock to prepare for the next cycle. One ATP molecule is required for each of these cycles. Which of the following events occurs after ATP binds to the myosin? A. the power stroke resulting in the sliding of the actin along the myosin molecules B. recocking of the myosin head C. release of the myosin head from the actin binding site D. binding of the myosin head to an active site on the actin

C. release of the myosin head from the actin binding site

Which of the following terms refers to a chain of sarcomeres? A. muscle B. myofiber C. myofibril D. myofilament

C. myofibril

Which of the following sarcomeric bands does not undergo a change in lenght during the contraction of a skeletal muscle? A. A band B. H band C. I band D. J band

A. A band

Which of the following sarcomeric bands is composed entirely of actin filaments? A. A band B. H band C. I band D. J band

C. I band

Dihydropyridine (DHP) channels are part of which of the following structures? A. Sarcoplasmic reticulum B. Plasmalemma C. T tubules D. Z discs

C. T tubules

Ryanodine-sensitive calcium ion release channels are part of which of the following structures? A. sarcoplasmic reticulum B. plasmalemma C. t tubules D. z discs

A. sarcoplasmic reticulum

Which of the following events occurs first during the transmission of a signal from an alpha motor neuron to a skeletal muscle fiber? A. end-plate depolarization (EPP) B. calcium ion influx into axon terminal C. exocytosis of synaptic vesicles D. sarcolemma action potential

B. calcium ion influx into axon terminal

Which of the following represents the factor by which the concentration of calcium ions increases in the cytosol after release from the sarcoplasmic reticulum? A. 10 B. 50 C. 100 D. 1000

C. 100 from 0.1 umol/L to 10 umol/L

Which of the following maintains an optimum calcium concentration gradient to facilitate return of calcium to SR? A. calsequestrin B. SERCA C. DHP D. ryanodine

A. calsequestrin

Fast twitch fibers have which of the following characteristics? A. they are reddish in color compared to slow twitch fibers B. they have more mitochondria than slow twitch fibers C. they have more myoglobin than slow twitch fibers D. they are more fatigable than slow twitch fibers

D. they are more fatigable than slow twitch fibers

Which of the following represents an example of an eccentric contraction? A. the triceps muscle during the throwing of a ball B. the triceps muscle while raising the body from the floor during a push-up C. the triceps muscle while lowering the body from the floor during a push-up D. the biceps muscle while raising the body during a pull-up

C. the triceps muscle while lowering the body to the floor during a push-up

Which of the following types of neurons would transmit an action potential the fastest? A. small diameter, non-myelinated B. small diameter, myelinated C. large diameter, myelinated D. large diamter, non-myelinated

C. large diameter, myelinated

Saltatory conduction is characteristic of which part of a typical neuron? A. dendrite B. nerve cell body C. axon hillock D. axon

D. axon jumps from node to node

A selectivity filter with carbonyl oxygens is associated with which of the following kinds of ion channels? A. gated sodium B. non-gated sodium C. potassium D. chloride

C. potassium

The resting potential for a typical neuron, such as a motor neuron, is best represented by which of the following potentials? A. 74 mV B. -74 mV C. 90 mV D. -90 mV

D. -90 mV

What is the role of calcium in muscle contraction?

binds to Troponin, exposing the myosin binding site on tropomyosin

What is the role of ATP in muscle contraction?

- used by SERCA to pump calcium back into the sarcoplasmic reticulum - causes myosin to release from actin - pumping of sodium/potassium to reestablish resting potential

3 major characteristics of an action potential

1. all or none; either occurs or it doesn't 2. self-propogating 3. non-decremental; no strength decrease

What covers the: 1. muscle 2. fascicle 3. myofiber

1. epimysium 2. perimysium 3. endomysium

Structural organization of a muscle from largest to smallest

Muscle --> fascicle --> myofiber -> myofibril --> myofilament

Isometric vs Isotonic

Isometric - inc tension, no change in length Isotonic - inc. in length

Eccentric vs Concentric

Eccentric - muscle lengthens Concentric - muscle shortens

Fast Twitch Fiber characteristics

- light and white - lower levels of mitochondria/myoglobin - high levels of ATPase - anaerobic - lower stamina

Slow Twitch Fiber characteristics

- dark and red - high levels of mitochondria/myoglobin - low levels of ATPase - aerobic

During the conduction of a signal from the SA node to the ventricular fibers, there is a .16 sec delay from the initial origin of the signal until onset of ventricular contraction. More than half of this delay occurs in which of the following areas of the transmission pathway? A. SA node B. AV node C. SA fibers D. penetrating bundles

B. AV node

In a typical ECG, which of the following waves occurs at the beginning of the contraction of the atria? ``` A. T B. R C. S D. P E. Q ```

D. P

Which of the following events is generally not seen on a typical ECG? A. Atrial depolarization B. Atrial repolarization C. Ventricular depolarization D. Ventricular repolarization

B. atrial depolarization

Which of the following is the direction of bipolar lead III? A. 0 degrees B. 60 degrees C. 90 degrees D. 120 degrees

D. 120 degrees

Of the three bipolar leads, which one is connected to both left and right arms? A. lead I B. lead II C. lead III D. all leads are connected to only one arm each

A. lead I

Of the three bipolar leads, which one would have the highest amplitude for the normal QRS wave, and which of the following reasons would explain this high amplitude? A. Lead I, because it is most perpendicular to the vector for the depolarization wave B. Lead I, because it is msot parallel to the vector for the depolarization wave C. Lead II, because it is most perpendicular to the vector of the depolarization wave D. Lead II, because it is most parallel to the vector for the depolarization wave

D. Lead II, because it is most parallel to the vector for the depolarization wave

Which of the following represents the mean electrical axis of the normal ventricles? ``` A. 59 degrees B. 67 degrees C. 120 degrees D. 157 degrees E. 270 degrees ```

A. 59 degrees

Which of the following conditions may result in tachycardia? ``` A. toxic conditions of the heart B. increased body temperature C. sympathetic nerve stimulation D. all of the above E. B and C only ```

D. all of the above

Circus movements are the basis of heart fibrillation. Which of the following statements is NOT true? A. Fibrillation may occur when the refractory period of the muscle is greatly shortened B. Fibrillation may occur when the pathway around the circle is too short C. Fibrillation may occur when the conduction velocity slows down D. Fibrillation may occur when the heart becomes dilated

B. Fibrillation may occur when the pathway around the circle is too short

84% of the blood volume is in the systemic circulation. Of this, 64% is in which of the following vessels? A. Capillaries B. Systemic arterioles C. Veins D. Arterioles

C. Veins

Blood flow resistance is inversely (indirectly) proportional to which of the following? A. viscosity B. vessel diameter C. density D. both A and C

B. vessel diameter

If rate of blood flow through the entire circulatory system (= cardiac output) = 100 ml/sec AND the pressure difference from the systemic arteries to the systemic veins = 100 mm Hg; the total peripheral resistance is equal to...? A. 10 PRU B. 1 PRU C. 0.01 PRU D. 100,000 PRU

B. 1 PRU Resistance = pressure difference/cardiac output

Reynolds number is a measure of which of the following parameters? A. Tendency for turbulence B. Blood pressure C. Conductance D. Resistance

A. Tendency for turbulence

Which of the following represents the viscosity of blood with a hematocrit of 38-42? A. 1.5 B. 3.0 C. 38 D. 42

B. 3.0

Consider the following statements: (1) Veins are about 8 times more distensible than arteries (2) Vascular compliance is directly proportional to volume increase and indirectly proportional to pressure. A. only statement 1 is true B. only statement 2 is true C. both statements are true D. both false statements are false

C. both statements are true

Which of the following properties is a measure of the ease with which a hollow viscus may be distended? A. Elastance B. Compliance C. Resistance D. Distensibility

B. Compliance

Which of the following relationships is correct? A. The greater the amount of elastic tissue in a blood vessel, the higher the compliance and the lower the elastance B. The greater the amount of elastic tissue in a blood vessel, the higher the compliance and the elastance C. The greater the amount of elastic tissue in a blood vessel, the lower the compliance and elastance D. The greater the amount of elastic tissue in a blood vessel, the lower the compliance and the greater the elastance

D. The greater the amount of elastic tissue in a blood vessel, the lower the compliance and the greater the elastance

High resistance in which of the following groups of vessels results in a disappearance in the phasic pressure pattern such as seen in the aorta? A. pulmonary arteries B. systemic arterioles C. systemic veins D. pulmonary capillaries

B. systemic arterioles

The least amount of damping of the pressure pulses would occur in which of the following components of the circulatory system? A. femoral artery B. arterioles C. capillaries D. venules

A. femoral artery

Precapillary sphincters are associated with which of the following types of vessels? A. small arteries B. arterioles C. metarterioles D. capillaries

C. metarterioles

The forces that determine whether fluid will move out of the blood into the interstitial fluid or in the opposite direction are referred to as Starling forces. Which of the following forces tends to move fluid inward at the arterial end of the capillary? A. capillary hydrostatic pressure B. negative interstitial free fluid pressure C. plasma colloid osmotic pressure D. interstitial fluid colloid osmotic pressure

C. plasma colloid osmotic pressure

If mean capillary pressure is 17.3 mm Hg; and negative interstitial free fluid pressure is 3.0 mm Hg; and interstitial fluid colloid osmotic pressure is 8.0 mm Hg; and plasma colloid osmotic pressure is 28.0 mm Hg; what is the total inward force? A. 17.3 mm Hg B. 20.3 mm Hg C. 28.0 mm Hg D. 28.3 mm Hg

C. 28.0 mm Hg

In any tissue in the body, a rapid increase in arterial pressure causes an immediate rise in blood flow. But within less than a minute, the blood flow in most tissues returns almost to the normal level even through the arterial pressure is kept elevated. This return of flow toward normal is due to which of the following events? A. autoregulation of blood flow B. tubuloglomerular feedback C. sympathetic response D. means systemic pressure feedback

A. autoregulation of blood flow

Which of the following factors is most responsible for controlling the rate of blood flow to each tissue of the body so that it is precisely controlled in relation to tissue need? A. sympathetic system B. renin-aldosterone-angiotensinogen system C. oxygen and accumulation of tissue waste products D. constriction of large venous reservoirs

C. oxygen and accumulation of tissue waste products

Which of the following substances would NOT result in vasoconstriction? A. Epinephrine/norepinephrine B. Angiotensin II C. Nitric Oxide D. Endothelin

C. Nitric Oxide

Vasodilators (4)

nitric oxide, ANP, bradykinins, histamine

Vasoconstrictors (6)

epinephrine/norepinephrine, angiotensin II, endothelin, vasopressin, catecholamines, thromboxane

Signals from the peripheral baroreceptors have which of the following effect(s) on the cardiac centers in the brain stem? A. inhibit vasoconstrictor and excite vasodilator centers B. inhibit both vasoconstrictor and vasodilator centers C. inhibit vasodilator and excite vasoconstrictor centers D. excite both vasoconstrictor and vasodilator centers

A. inhibit vasoconstrictor and excite vasodilator centers

Which of the following factors results in decreased peripheral resistance (vessel dilation) leading to decreased blood pressure? A. increased production of angiotensin II B. increased release of thromboxane C. increased release of catecholamines D. increase in atrionatriuretic peptide (ANP)

D. increase in atrionatriuretic peptide (ANP)

Which of the following factors is related to primary (essential) hypertension? A. Sedentary life style B. Preeclampsia C. Renal artery constriction D. coarctation of the aorta

A. sedentary life style C and D are part of 2nd hypertension

Characteristics of primary hypertension would NOT include which of the following? A. sympathetic nerve activity B. increase in cardiac output C. activation of renal pressure natriuresis mechanism D. increased levels of angiotensin II and aldosterone in obese partients

C. activation of renal pressure natriuresis mechanism

Angiotensinogen is converted to angiotensin I by renin. Angiotensin I is then converted to angiotensin II, which then results in an increase in extracellular fluid volume. Angiotensinogen is derived from which of the following sources? A. Kidney B. Liver C. Adrenal cortex D. Adrenal medulla

B. Liver Renin comes from the kidney

Blocking of the renin-angiotensin mechanism would have with of the following effects on arterial pressure? A. it would have no effect on arterial pressure B. it would result in sodium and water retention and increased arterial pressure C. it would result in sodium and water retention and decreased arterial pressure D. it would result in sodium and water loss and increased arterial pressure E. it would result in sodium and water loss and decreased arterial pressure

E. it would result in sodium and water loss and decreased arterial pressure

Using the Fick principle for calculating the cardiac output, the patients oxygen consumption volume could be divided by which of the following? A. the difference between the oxygen concentration in the systemic arterial blood and the systemic mixed venous blood B. the difference between the oxygen concentration in the systemic arterial blood and the pulmonary vein C. the difference between the oxygen concentration in the systemic mixed venous blood and the pulmonary vein D. the difference between the oxygen concentration in the systemic mixed venous blood and the pulmonary artery

A. the difference between the oxygen concentration in the systemic arterial blood and the systemic mixed venous blood

Which of the following factors would cause a hypereffective heart? A. hypertrophy of the heart B. valvular heart disease C. inhibition of nervous excitation of the heart D. coronary artery block

A. hypertrophy of the heart other causes of hypereffective (pump more than you need): nervous stimulation, exercise via nervous system

A certain dietary deficiency condition weakens the heart. Under these conditions, if the systemic filling pressure is 11.5, the right arterial pressure is 9 mm Hg, and the cardiac output is 8 L/min, this type of heart failure would be best referred to as which of the following? A. low-output cardiac failure B. left-right cardiac shunt C. right-left cardiac shunt D. high-output cardiac failure

D. high-output cardiac failure

Which of the following factors is NOT quantitatively expressed on the venous return curve? A. mean systemic filling pressure B. right arterial pressure C. blood flow resistance between peripheral vessels and right atrium D. cardiac output

D. cardiac output

An increase in blood volume would have which of the following effects on the cardiac and vascular function curves? A. a decrease in mean systemic pressure and a shift of the vascular function curve to the right B. a decrease in mean systemic pressure and a shift of the vascular function curve to the left C. an increase in mean systemic pressure and a shift of the vascular function curve to the right D. an increase in mean systemic pressure and a shift of the vascular function curve to the left

C. in increase in mean systemic pressure and a shift of the vascular function curve to the right

During exercise, total peripheral resistance decreases because of the effect of which of the following? A. the sympathetic nervous system on splanchnic nerves B. the parasympathetic nervous system on skeletal muscle arterioles C. local metabolites on skeletal muscle arterioles D. local metabolites on cerebral arterioles

C. local metabolites of skeletal muscle arterioles

When both the mean systemic filling pressure and right atrial pressure are 7, what is the venous return rate? A. 5.2 liters per minute B. 5 liters per minute C. 4 liters per minute D. 0 liters per minute

D. 0 liters per minute

Which of the following would not occur as a result of a mass discharge of the sympathetic system during exercise? A. strong contraction of the coronary arteries B. increase in the mean systemic filling pressure due to contraction of the muscle walls of veins C. increase in heart rate D. strong contraction of most peripheral arteries

A. strong contraction of the coronary arteries

Which of the following is the primary controller of coronary artery blood flow? A. sympathetic innervations B. parasympathetic innervations C. local muscle metabolism D. systemic venous resistance

C. local muscle metabolism

Which of the following mechanisms would most likely serve as the major immediate factor in compensating for an acute myocardial infarction? A. renal angiotensin system B. aldosterone C. sympathetic response D. intravenous fluid therapy

C. sympathetic response

Which of the following pairs of potentially fatal conditions may follow severe acute left heart failure? A. pulmonary vascular congestion and pulmonary edema B. systemic vascular congestion and pulmonary edema C. systemic vascular congestion and systemic edema D. pulmonary vascular congestion and systemic edema

A. pulmonary vascular congestion and pulmonary edema

The second heart sound is due to which of the following events? A. closure of atrioventricular valves at onset of ventricular systole B. opening of atrioventricular valves at onset of atrial systole C. closure of semilunar valves at onset of ventricular systole D. opening of semilunar valves at onset of ventricular diastole

C. closure of semilunar valves at onset of ventricular systole

Compared to non-progressive shock, which of the following is one of the most important features if progressive shock? A. sympathetic reflexes B. hemorrhagic in origin C. cardiac depression D. increased vascular permeability

B. hemorrhagic in origin

Spinal anesthesia has which of the following effects on cardiac output and venous return? A. it decreases venous return but increases cardiac output B. it decreases venous return and cardiac output C. it increases venous return but decreases cardiac output D. it increases venous return and cardiac output

B. it decreases venous return and cardiac output

Which of the following conditions increases the systemic filling pressure by decreasing vascular compliance? A. lying down B. renal-angiotensin-aldosterone system C. burn trauma D. inhibition of the sympathetic system

A. lying down

ADH (anti-diuretic hormone) is formed in the supraoptic and paraventricular nuclei. It is secreted by specialized neurons from which of the following areas? A. adrenal cortex B. adrenal medulla C. anterior pituitary D. posterior pituitary

D. posterior pituitary

Which of the following factors would decrease venous return and increase right atrial pressure? A. Hemorrhage B. Vasodilation of arterioles C. Decreased venous compliance D. Increased ADH secretion

A. Hemorrhage

Which of the following substances would result in vasodilation? A. epinephrine/norepinephrine B. angiotensin II C. nitric oxide D. endothelin

C. nitric oxide

Vascular distensibility is directly proportional to which of the following? ``` A. increase in volume B. original volume C. increase in pressure D. original pressure E. Both A and C ```

A. increase in volume Compliance = V/P

Which of the following properties is a measure of the ease with which a hollow structure may be distended? A. elastance B. compliance C. resistance D. distensibility

B. compliance

Which of the following factors affect(s) pulse pressure? ``` A. vascular elastance B. arterial compliance C. stroke volume D. all of the above E. B and C only ```

E. B and C only Pulse pressure = stroke volume / arterial compliance

Which of the following is the most important means for the exchange of substances between the blood and the interstitial fluid? ``` A. blood hydrostatic pressure B. capillary hydrostatic pressure C. diffusion D. interstitial fluid hydrostatic pressure E. osmosis ```

C. diffusion

Baroreceptors are extremely abundant in carotid sinuses and the walls of the aortic arch. Which of the following transmit signals from baroreceptors to cranial nerve IX (glossopharyngeal nerve)? A. Mueller nerves B. Hering nerves C. Starling nerves D. Purkinje nerves

B. Hering nerves

Approximately how much of the total cardiac output is received by the kidneys? A. 25% B. 50% C. 75% D. 100%

A. 25%

Which of the following describes the effects of adding hypertonic sodium chloride to extracellular fluid after osmotic equilibrium is reached? A. both extracellular and intracellular volumes decrease and osmolarity in both compartments increases B. the extracellular volume decreases and the intracellular volume increases, osmolarity in both compartments increases C. the extracellular volume increases and the intracellular volume decreases, osmolarity in both compartments increases D. both extracellular and intracellular volumes increases and osmolarity in both compartments increases

C. the extracellular volume increases and the intracellular volume decreases, osmolarity in both compartments increases

The osmolar gap can be determined from the basic metabolic profile and helps to narrow the differential diagnosis. Which of the following can elevate the osmolar gap? A. Ethanol B. Glycerol C. Sucrose D. Glucose

A. Ethanol other elevators of osmolar gap: ethylene glycol, mannitol, methanol, acetone

Which of the following characteristics would be true for cortical nephrons? A. glomeruli lie deep in the cortex near the medulla of the kidney and have short loops of Henle B. glomeruli lie deep in the cortex near the medulla of the kidney and have long loops of Henle C. glomeruli lie in the outer cortex and have short loops of Henle D. glomeruli lie in the outer cortex and have long efferent arterioles

C. glomeruli lie in the outer cortex and have short loops of Henle

Renal autoregulation refers to the relative constancy of GFR and renal blood flow. A decrease in arterial pressure and glomerular filtration rate ultimately leads to a reduction in the concentration of sodium ions at the macula densa. This results in which of the following responses that ultimately restors GFR? A. release of renin by juxtaglomerular apparatus B. release of endothelin by glomerular capillaries C. release of nitric oxide by the vasa recta endothelium D. release of angiotensin II by the juxtaglomerular apparatus

A. release of renin by the juxtaglomerular apparatus

GFR is determined by the net filtration pressure and the glomerular capillary filtration coefficient. Which of the following factors has the greatest effect on increasing GFR? A. Glomerular capillary colloid osmotic pressure B. Bowman's capsule hydrostatic pressure C. Bowman's capsule colloid osmotic pressure D. Glomerular hydrostatic pressure

D. Glomerular hydrostatic pressure 60 mm Hg

Minimum change disease occurs when the negative charges on the filtration membrane of the glomerulus are not present. What abnormality in the urine would be expected under these conditions? A. Urine would contain numerous red blood cells B. Urine would contain excess albumin C. Urine would contain excess sodium and chloride D. Urine would be less concentrated

B. Urine would contain excess albumin

A number of hormones are involved in the control of glomerular filtration rate. Which of the following preferentially constricts the efferent arterioles but has little to no effect on the afferent arterioles? A. Bradykinin B. Angiotensin II C. Endothelial-derived nitric oxide D. Endothelin

B. Angiotensin II

Which of the following, in liter/day, represents the GFR in the average adult human? A. 3 B. 125 C. 180 D. 360

C. 180 liters/day OR 125 mL/min

An increase in which of the following factors will result in a decrease in glomerular hydrostatic pressure? ``` A. Arterial pressure B. Afferent arteriolar resistance C. Efferent arteriolar resistance D. Both B and C E. All of the above ```

B. Afferent arteriolar resistance

Approximately how much of the total cardiac output is received by the kidneys? A. 25% B. 50% C. 75% D. 100%

A. 25%

The macula densa is found in which of the following parts of the renal tubule? A. Proximal convoluted tubule B. Thin descending limb of Henle C. Thick ascending limb of Henle D. Distal convoluted tubule

D. Distal convoluted tubule

The thin descending loop of Henle is highly permeable to which of the following? A. sodium B. water C. urea D. amino acids

B. water moderately permeable to sodium and urea

Aldosterone is an important regulator of sodium reabsorption and potassium secretion; one of its main targets is...? A. podocytes B. principal cells C. intercalated cells D. cells of the macula densa

B. principal cells intercalated cells = potassium reabsorption and hydrogen secretion

Which of the following cells play a major role in the secretion of potassium? A. intercalated cells B. principal cells C. chief cells D. podocytes

B. principal cells

Most potassium reabsorption occurs at which of the following sites? A. ascending loop of Henle B. distal convoluted tubule C. proximal convoluted tubule D. collecting duct

C. proximal convoluted tubule

Primary active hydrogen secretion involves a hydrogen transporting ATPase. It occurs in which of the following parts of the renal tubules? A. descending limb of Henle B. ascending limb of Henle C. late distal tubules in intercalated cells D. early collecting tubules in principal cells

C. late distal tubules in intercalated cells

ADH (anti-diuretic hormones) is formed in the supraoptic and paraventricular nuclei. It is secreted by specialized neurons from which of the following areas? A. adrenal cortex B. adrenal medulla C. anterior pituitary D. posterior pituitary

D. posterior pituitary

A normal 70 kg human must excrete about 600 mOsm of solute each day in order to get rid of waste products of metabolism and ions that are ingested. The maximal urine concentration ability is 1200 mOsm/L. Which of the following represents the obligatory urine volume that must be excreted each day to get rid of metabolic waste products? A. 1.0 L/day B. 0.5 L/day C. 0.3 L/day D. 0.0 L/day

B. 0.5 L/day

ADH acts on which of the following regions of the nephron? A. proximal convoluted tubule B. descending loop of Henle C. ascending loop of Henle D. distal convoluted tubule

D. distal convoluted tubule

Which of the following reflects the amount of urine that the kidneys can excrete per day when there is a large excess of water? A. 180 liters B. 75 liters C. 20 liters D. 4 liters

C. 20 liters

Which of the following reflects the maximum urine concentration that can be produced by the kidneys? A. 6000-7000 mOsml/L B. 5500-6000 mOsml/L C. 1200-1400 mOsml/L D. 2000-2400 mOsml/L

C. 1200-1400 mOsml/L

Osmoreceptors cells are located in which of the following regions? A. adjacent to carotid bodies B. in the macula densa C. in the anterior part of the third ventricle D. in the distal collecting ducts

C. in the anterior part of the third ventricle

Which of the following segments of the nephron is NOT permeable to water? A. proximal convoluted tubule in the presence of ADH B. descending loop of Henle in the presence of ADH C. ascending loop of Henle in the presence of ADH D. distal convoluted tubule in the presence of ADH

C. ascending loop of Henle in the presence of ADH

Which of the following plays a major role in stimulating potassium excretion by the kidney tubules? A. aldosterone B. angiotensin II C. sodium ion D. PTH

A. aldosterone PTH = calcium reabsorption

Approximately how much of the body's supply of calcium is stored in the bone? A. 1% B. 47% C. 78% D. 99%

D. 99%

How much of the filtered calcium is excreted in the kidneys? A. 1% B. 47% C. 78% D. 99%

A. 1%

Which of the following cells reabsorb potassium during potassium depletion? A. intercalated cells B. principal cells C. chief cells D. podocytes

A. intercalated cells principal cells = potassium secretion

A high potassium intake would have which of the following effects on potassium excretion associated with increased renal tubular flow rate? A. potassium excretion would increase with increased tubular flow rate B. potassium excretion would decrease with increased tubular flow rate C. there would be little effect D. tubular flow rate would be decreased

A. potassium excretion would increase with increased tubular flow rate

Which of the following describes a valid change in potassium distribution due to an acid-base abnormality? A. Metabolic acidosis decreases extracellular K concentration B. Metabolic alkalosis increases extracellular K concentration C. Metabolic acidosis increases extracellular K concentration D. Both A and B are valid

C. Metabolic acidosis increases extracellular K concentration metabolic alkalosis = decreased extracellular K concentration

Which of the following buffer systems is most important in buffering renal tubular fluid? A. phosphate buffer systems B. carbonate buffer systems C. bicarbonate buffer systems D. hemoglobin buffer systems

A. phosphate buffer systems

Compounds that dissociate incompletely into hydrogen ions and a conjugate base are members of which of the following compounds? A. strong acids B. weak acids C. strong bases D. weak bases

B. weak acids

The bicarbonate buffer system consists of a bicarbonate salt and which of the following? A. weak acid B. strong acid C. weak base D. strong base

A. weak acid

Which of the following buffer systems is the most important extracellular buffer systems? A. phosphate buffer system B. carbonate buffer system C. bicarbonate buffer system D. hemoglobin buffer system

C. bicarbonate buffer system

Most bicarbonate reabsorption occurs in which of the following parts of the renal tubule? A. proximal tubule B. descending loop of Henle C. ascending loop of Henle D. distal tubule

A. proximal tubule

Which of the following occurs when a decrease in bicarbonate ion results in a decrease in the ratio of bicarbonate ion to carbon dioxide in the extracellular fluid? A. respiratory acidosis B. respiratory alkalosis C. metabolic acidosis D. metabolic alkalosis

C. metabolic acidosis

Respiratory alkalosis due to a decrease in carbon dioxide concentration caused by hyperventilation is compensated for by which of the following mechanisms? A. increased ventilation rate B. decreased ventilation rate C. renal excretion of bicarbonate ion D. renal addition of new bicarbonate ion to extracellular fluid

C. renal excretion of bicarbonate ion

Which of the following would be a result of increased levels of angiotensin II? A. decreased blood pressure B. increase vasoconstriction C. increased natriuresis D. decreased aldosterone levels

B. increased vasoconstriction

A 1-sodium, 2-chloride, 1-potassium co-transporter is found in the lumbrical membrane of which part of the renal tubule? A. proximal convoluted tubule B. thin descending limb of Henle C. thick ascending limb of Henle D. distal convoluted tubule

C. thick ascending limb of Henle

If tidal volume is 0.5 liters, dead space is 0.15 liters, and breathing rate is 12 time per minute, calculate the minute ventilation. A. 1.8 liters B. 4.0 liters C. 6.0 liters D. 7.8 liters

C. 6.0 liters minute ventilation = 0.5 x breathing rate

The solubility of oxygen = 0.024; the solubility of carbon dioxide = 0.57. Because carbon dioxide is more soluble in water than oxygen, it will exert a partial pressure (for a given concentration) that is less than 1/20th that of oxygen. This relationship between partial pressures and solubility illustrates which of the following gas laws? A. Henry's B. Boyle's C. Dalton's D. Euclid's

A. Henry's

If tidal volume is 0.5 liters, dead space is 0.15 liters, and breathing rate is 12 times per minute, calculate the minute alveolar ventilation. A. 1.8 liters B. 3.5 liters C. 4.2 liters D. 6.0 liters

C. 4.2 liters alveolar ventilation = (tidal vol. - dead space) x breath rate

Humidification of air in the alveoli has which of the following effects on the partial pressures of nitrogen and oxygen in the alveoli? A. it increases the partial pressure of each of the other gases B. it decreases the partial pressures of each of the other gases C. it has no effect on the partial pressures of each of the other gases D. it increases the partial pressure of oxygen but decreases the partial pressure of nitrogen in alveolar air

B. it decreases the partial pressures of each of the other gases

The range in the pressure change (in cm of water) in alveolar pressure during inspiration is expressed by which of the following? A. 0 to -1 B. -5 to -7.5 C. -7.5 to -5 D. -1 to 0

A. 0 to -1

What would be the Va/Q ratio for alveolar air with a PO2 of 104 and a PCO2 of 40? A. 2.5 B. 0.8 C. 0 D. infinity

B. 0.8 Normal = pO2 - 100 and pCO2 - 40

Which of the following would be characteristic of alveoli lacking perfusion, as in the case of a pulmonary embolism? A. Va/Q ratio = infinity B. Va/Q = 0 C. Blood gas composition remains unchanged D. Both B and C are characteristic

A. Va/Q ratio = infinity

Under normal conditions at rest, which of the following patterns regarding pulmonary blood flow would be most likely? A. Apices: zone 1; middle part of lungs: zone 1; lower part of lungs: zone 3 B. Apices: zone 2; middle part of lungs: zone 2; lower part of lungs: zone 3 C. Apices: zone 2; middle part of lungs: zone 3; lower part of lungs: zone 3 D. Apices: zone 3; middle part of lungs: zone 2; lower part of lungs: zone 1

C. Apices: zone 2; middle part of lungs: zone 3; lower part of lungs: zone 3

The pulmonary circulation can be divided into two systems. Which of the following describes the system supplying the trachea, bronchial tree and the rest of the intersititum? A. high pressure - low flow B. high pressure - high flow C. low pressure - low flow D. low pressure - high flow

A. high pressure - low flow

Which of the following represents the mean pulmonary arterial pressure in mmHg? A. 7 B. 15 C. 25 D. 125

B. 15

The most common cause of pulmonary edema is left sided heart failure or mitral valve disease. Pulmonary edema occurs when pulmonary capillary pressure exceeds which of the following levels? A. 07 mmHg B. 15 mmHg C. 20 mmHg D. 25 mmHg

D. 25 mmHg pulmonary edema likely to develop above 30 mmHg