Human Phys Final

A typical value of intraplural pressure (relative to atmospheric pressure) at the end of expiration (resting breathing) is approximately +6 mm Hg +3 mm Hg 0 mm Hg -4 mm Hg -12 mm Hg

-4

Place the following blood vessels that carry blood to and within the kidney in the order in which blood passes through them. 1) afferent arteriole 2) efferent arteriole 3) glomerulus 4) peritubular capillary 4, 2, 3, 1 1, 3, 2, 4 4, 3, 2, 1 1, 2, 3, 4 3, 4, 2, 1

1, 3, 2, 4

Under normal conditions, the aortic pressure after opening of the aortic value would be closest to which of the following values: 60 mm Hg 80 mm Hg 93 mm Hg 100 mm Hg 120 mm Hg

120

Put these phases of the cardiac cycle in the correct order. (start with #2) 1. isovolumic contraction 2. beginning of atrial systole 3. completion of ventricular filling 4. beginning of ventricular systole 5. ventricular relaxation 6. ventricular ejection 2, 3,1, 5, 6, 4 2, 3, 4, 6, 1, 5 2, 3, 4, 1, 6, 5 2, 1, 4, 3, 6, 5 2, 1, 4, 3, 5, 6

2, 3, 4, 1, 6, 5

Although the kidneys comprise about 1% of total body weight, at rest they receive approximately X% of cardiac output 2 5 10 20 50

20

An "average" 70 Kg male is breathing through a snorkel with a volume of 100 ml. If his tidal volume is 0.55 L and breathing rate is 10 breaths per minute, what is alveolar ventilation most likely to be? 1 L/min 1.5 L/min 3 L/min 4.5 L/min 5.5 L/min

3

With a normal tidal volume and a respiratory rate of 10 breaths per minute, alveolar ventilation would be approximately 5 liters per minute 3.5 liters per minute 1.5 liters per minute 7 liters per minute none of the above are even close

3.5

A substance that is filtered (not reabsorbed or secreted) and subsequently excreted would pass through the following segments of the nephron in what order? distal tubule proximal tubule peritubular capillaries Bowman's capsule descending limb of the Loop of Henle ascending Limb of the loop of Henle 3,4,2,6,5,1 3,4,2,5,6,1 4,2,6,5,1 4,1,5,6,2 4,2,5,6,1

4,2,5,6,1

In a patient with hypertension, a physician records a systolic blood pressure of 160 mm Hg and a diastolic pressure of 90 mm Hg. The patient's heart rate was 70 beats per minute. Further studies showed an end diastolic volume of 140 ml and an end systolic volume of 70 ml. What is this patient's cardiac output? 4900 ml/min 70 ml/min 490 ml/min 1400 ml/min not enough information is provided to determine cardiac output.

4900 ml/min

erythropoietin

A hormone produced and released by the kidney that stimulates the production of red blood cells by the bone marrow.

Which of the following determines whether a target tissue/cells respond to a paracrine signaling molecule. a) Concentration of the molecule released b)How far away the target is c) Type and number of receptors on the target d) A, B and C E) A and C

A, B and C

posterior pituitary

ADH (but made in the hypothalamus) and oxytocin

Which of the following is not a function of the hypothalamus? Activation of the sympathetic nervous system Activation of the parasympathetic nervous system Maintenance of body temperature and osmolarity Stimulation of the satiety and feeding centers Working with the limbic system to influence emotions and behavior

Activation of the parasympathetic nervous system

Antidiuretic hormone Is a peptide hormone released by the kidney to maintain water balance Acts to increase the permeability of the collecting ducts to water Acts on the collecting ducts to cause the secretion of water Acts to stimulate sodium reabsorption, and thereby promote water retention by the body Produces antidiuresis primarily by decreasing GFR

Acts to increase the permeability of the collecting ducts to water

What is the role of troponin in muscle contraction? After binding to calcium ions, it moves tropomyosin away from the myosin binding site on actin Troponin causes additional calcium release from the sarcoplasmic reticulum Troponin increases the ATPase activity of myosin Troponin phosphorylates myosin Both c and d

After binding to calcium ions, it moves tropomyosin away from the myosin binding site on actin

glycolytic fibers have few mitochondria, lack myoglobin, and are lighter in color.

All muscle fibers in a motor unit are of the same type; a single motor unit contains only one type of muscle fiber.

Injection of hexamethonium, a drug that blocks autonomic ganglionic transmission, into a healthy resting young adult would cause each of the following except An increase in heart rate A decrease in total peripheral resistance Dilation of the bronchioles An increase in alveolar ventilation A decrease in epinephrine secretion from the adrenal medulla

An increase in alveolar ventilation

Which of the following statements does NOT correctly describe antibodies? Antibodies are secreted by plasma cells. Antibodies protect against viruses by binding to them and presenting them to phagocytes Antibodies protect against viruses by binding to them and neutralizing them Antibodies activate complement Antibodies protect against viruses by binding to them and perforating them

Antibodies protect against viruses by binding to them and perforating them

Which statement describes the fastest muscle fibers, but not the slowest muscle fibers? Contain myoglobin to increase oxygen supply to the muscle fiber Use aerobic metabolism to generate ATP in the muscle Have smaller diameter fibers Are less efficient at producing ATP Are more resistant to developing fatigue.

Are less efficient at producing ATP

What will happen to blood flow to a cluster of alveoli that are provided no fresh air when a terminal bronchiole becomes obstructed? Blood flow to those alveoli will increase so that blood can efficiently pick-up the little oxygen left in the affected alveoli Blood flow to those alveoli will be unaffected, as alveolar PO2 has no impact on pulmonary blood flow Blood flow to those alveoli will decrease, due to a decrease in activity of sympathetic fibers innervating the pulmonary arterioles Blood flow to those alveoli will decrease because local oxygen concentration has a large effect on constriction of pulmonary arterioles the arterial chemoreceptor reflex will cause an increase in blood flow to the affected alveoli

Blood flow to those alveoli will decrease because local oxygen concentration has a large effect on constriction of pulmonary arterioles

What distinguishes endocrine signaling from other types of signaling? It occurs only within a localized area The targets of endocrine signaling are exclusively intracellular receptors Endocrine signaling involves release of signaling molecules into the bloodstream Endocrine signaling cannot change membrane permeability by opening ligand-gated receptors Compared to neural signaling, endocrine signaling is very fast and precise.

Endocrine signaling involves release of signaling molecules into the bloodstream

Which of the following would decrease glomerular filtration fraction? Increased blood protein concentration Decreased hydrostatic pressure in Bowman's space Vasodilation in the afferent arteriole Increased glomerular capillary blood pressure increased size of filtration slits

Increased blood protein concentration

Which of the following accurately describes blood flow from the toes to the lungs? Inferior vena cava, right atrium right ventricle, aortic valve, pulmonary artery Inferior vena cava, right atrium right ventricle, pulmonary valve, pulmonary artery Superior vena cava, right atrium, right ventricle, pulmonary valve, pulmonary artery Inferior vena cava, right ventricle, right atrium, pulmonary valve, pulmonary vein Inferior vena cava, pulmonary valve, right atrium, right ventricle, pulmonary artery

Inferior vena cava, right atrium right ventricle, pulmonary valve, pulmonary artery

Several years ago a promising drug (terfenadine) for the treatment of allergies was taken off the market because it caused a cardiac side effect called "prolonged Q-T syndrome", a lengthening of the Q-T segment of the ECG. This side effect was traced to an action of the drug on a specific ion channel in the heart. Which of the following could result in prolonged Q-T syndrome? Reducing the If current in SA node cells Reducing the threshold for opening of voltage-gated Ca++ channels in SA node cells Increasing the speed at which cardiac myocyte voltage-gated Na+ channels become blocked Partially blocking voltage-gated Ca++ channels in cardiac ventricular myocytes Interfering with a specific type of K+ channel in cardiac ventricular myocytes

Interfering with a specific type of K+ channel in cardiac ventricular myocytes

How would the shape of an action potential change if TEA, a drug that blocks voltage-gated potassium channels, was applied to a biologically active neuron? Shorter duration of the action potential Little to no hyperpolarization phase would occur No upstroke would occur The action potential would have a more negative peak Both a and b

Little to no hyperpolarization phase would occur

Which of the following functions is most likely to be performed by a circumventricular organ? Measuring osmolarity of extracellular fluid Phosphorylation of myosin light chain Activation of sympathetic input to the cardiovascular system Coordination of limbic system emotional responses Processing somatosensory information

Measuring osmolarity of extracellular fluid

Which of the following conditions is met when the cell is at its resting membrane potential? All ions that the cell is permeable to are at their equilibrium potentials. The concentration of sodium inside the cell must be equal to the concentration of sodium outside of the cell. The concentration of potassium inside the cell must be equal to the concentration of potassium outside of the cell. b and c are true at rest NONE of the above are true at rest

NONE of the above are true at rest

Each of the following statements concerning peptide hormones is true except one. Identify the INCORRECT statement: Peptide hormones are first synthesized as prohormones (or pre-prohormones). Prohormones can be activated by post-translational modification before their release. Peptide hormones remain in the circulation for relatively short periods of time (e.g., shorter than steroid hormones). Peptide hormones interact with receptors on the cell surface of their target cells. Peptide hormones in the bloodstream are always bound to carrier proteins.

Peptide hormones in the bloodstream are always bound to carrier proteins.

Which of the following is a correct distinction between the sympathetic (SNS) and parasympathetic (PNS) branches of the ANS? Postganglionic fibers of the PNS use norepinephrine, whereas those of the SNS use acetylcholine. The SNS postganglionic cell bodies are present in a chain alongside the spinal cord, whereas the PNS ganglia are more peripherally distributed The PNS has long postganglionic fibers, whereas the SNS has quite short postganglionic fibers The PNS is activated during exercise, whereas the SNS is active during feeding. All of the above are correct

The SNS postganglionic cell bodies are present in a chain alongside the spinal cord, whereas the PNS ganglia are more peripherally distributed

When a blood vessel dilates, which of the following is TRUE? The resistance decreases, and flow decreases. The resistance increases, and blood pressure increases. The resistance decreases, and flow increases. The resistance decreases, and blood pressure increases The resistance increases, and velocity increases.

The resistance decreases, and flow increases.

Which of the following accurately describes the structure and function of intercalated disks in cardiac muscle? They contain desmosomes to connect adjacent cells together and keep them together during contraction They contain the T-tubules of the cardiac myocytes The intercalated disks store calcium that is released to bind to troponin and trigger muscle contraction The cell nuclei are contained in the intercalated disks None of the above, intercalated disks are only found in skeletal muscle

They contain desmosomes to connect adjacent cells together and keep them together during contraction

A thoracic spinal ventral root contains: axons of somatic motor neurons (but not B) axons of preganglionic sympathetic neurons (but not A) axons of preganglionic parasympathetic neurons axons of somatic sensory neurons both A and B

a and b

Consider the following homeostatic example. As carbon dioxide levels in blood increase, this is detected by sensory neurons with axons projecting into the brain stem. The increased signal provided to the brain stem by these sensory neurons causes an increase in the rate of breathing, thereby increasing the rate of loss of carbon dioxide in the expired air. This is an example of: a feedforward system a positive feedback system a negative feedback system a thermostat it is both a positive feedback and negative feedback system

a negative feedback system

In a skeletal muscle fiber a single twitch contraction lasts longer than the action potential because the muscle will continue to contract until it receives a signal to stop a single twitch contraction lasts longer than the action potential because the increase in cytosolic Ca++ lasts longer than the action potential a single twitch contraction has a similar time course to the action potential because it is caused by the action potential a single twitch contraction has a similar time course to the action potential because they share a common ionic mechanism a single twitch contraction is unrelated to the action potential, since the action potential is an electrical event and contraction is a mechanical event

a single twitch contraction lasts longer than the action potential because the increase in cytosolic Ca++ lasts longer than the action potential

Which of the following statements regarding B lymphocytes is NOT true? Each B cell clonal line recognizes a single antigen can secrete certain cytokines activation requires MHC class 1 proteins are activated by cytokines usually require T cells to be activated for B-cell activation

activation requires MHC class 1 proteins

The major function of bile in digestion is to stimulate bicarbonate secretion convert inactive pro-enzymes into active enzymes cause intestinal contractions aid in the breakdown of fat aid in the breakdown of starches

aid in breakdown fat

Norepinephrine is _________. an agonist at alpha adrenergic receptors and beta adrenergic receptors an antagonist at alpha adrenergic receptors and beta adrenergic receptors an agonist at one of these adrenergic receptors and an antagonist at the other an antagonist at cholinergic receptors an agonist at cholinergic receptors

an agonist at alpha adrenergic receptors and beta adrenergic receptors

The hormone insulin enhances the transport of glucose from the blood into most of the body's cells. Its secretion is controlled by a negative feedback system between the concentration of glucose in the blood and the insulin-secreting cells. Therefore, which of the following statements is correct? a decrease in blood glucose concentration stimulates insulin secretion, which in turn further lowers blood glucose concentration an increase in blood glucose concentration stimulates insulin secretion, which in turn lowers the blood glucose concentration a decrease in blood glucose concentration stimulates insulin secretion, which in turn increases the blood glucose concentration an increase in blood glucose concentration stimulates insulin secretion, which in turn further increases the blood glucose concentration. none of the above are correct.

an increase in blood glucose concentration stimulates insulin secretion, which in turn lowers the blood glucose concentration

Which vessels are large diameter, low-resistance vessels that function to distribute blood around the body? Arteries Arterioles Capillaries Venules Veins

arteries

The major site of sympathetic control of blood flow to a tissue is: arteries arterioles the heart metarterioles the sympathetic nervous system does not influence tissue blood flow

arterioles

Proteins in the diet are absorbed as free amino acids in the stomach as free amino acids in the small intestine as proteins in the small intestine as proteins in the large intestine as amino acids directly into lymph

as free amino acids in the small intestine

When air is not moving through the respiratory tract (and there is no obstruction), the pressure in the lungs is equal to pulmonary artery pressure transpulmonary pressure intrapleural pressure atmospheric pressure more than one of the above

atmospheric pressure

Which is true for movement of molecules through a membrane pore but not for facilitated diffusion? a) The transport proteins span the membrane b) The transport protein is open to the extracellular and intracellular cellular compartments at the same time. c) Molecules are moving down their concentration gradient d) Movement requires cleavage of ATP e) Movement requires the establishment of a sodium

b) The transport protein is open to the extracellular and intracellular cellular compartments at the same time.

You can estimate the relative number and complexity of synaptic inputs to a given neuron... based on how many axons that neuron has based on the extent and complexity of that neuron's dendritic branches based on how many neurotransmitter vesicles that neuron has based on how many mitochondria are in the axon terminal based on how many glial cells are surrounding the neuron

based on the extent and complexity of that neuron's dendritic branches

Depolarization of the AV node occurs during what portion of the ECG? between the P wave and the QRS complex between the QRS complex and the T wave during the T wave between the T and the P wave throughout the entire ECG

between the P wave and the QRS complex

Most of the oxygen transported by the blood is dissolved in plasma. bound to hemoglobin. in ionic form as solute in the plasma. bound to a plasma protein. carried by white blood cells.

bound to hemoglobin

A diuretic drug might result in a decrease in cardiac output because increased excretion by the kidneys would decrease blood volume causing a decrease in heart rate all diuretic drugs act by decreasing sympathetic nervous system activity, which would cause both a decrease in renal function and a decrease in heart rate by increasing excretion by the kidneys, blood volume would decrease thereby decreasing end diastolic volume which would decrease cardiac output. by increasing filtration by the kidneys, the macula densa would release a hormone that would decrease cardiac output. because diuretic drugs act on the kidney there is no way that they would result in a change in heart rate.

by increasing excretion by the kidneys, blood volume would decrease thereby decreasing end diastolic volume which would decrease cardiac output.

The hypothalamus controls prolactin secretion from the anterior pituitary gland primarily by sending action potentials directly to the anterior pituitary gland by secreting release-inhibiting hormones but not release-stimulating hormones by secreting release-stimulating hormones but not release-inhibiting hormones by secreting both release-inhibiting hormones and release-stimulating hormones the hypothalamus does not control the secretion of prolactin

by secreting both release-inhibiting hormones and release-stimulating hormones

A healthy young man has a total lung capacity of 6 L, a residual volume of 1 L, and an anatomic dead space of 150 ml. With a tidal volume of 500ml and a breathing rate of 10/minute, which of the following statements is/are correct? his alveolar ventilation would be 5 L/minute doubling his breathing rate would exactly double his minute volume. doubling the tidal volume would exactly double his alveolar ventilation all of the above both b and c

doubling his breathing rate would exactly double his minute volume.

Left ventricular pressure is higher than pressure in the aorta during... ventricular systole only atrial systole only atrial systole and ventricular systole ventricular diastole only All of the answers are correct

ventricular systole only

The partial pressure of oxygen in arterial blood is approximately ________ mm Hg. 40 45 50 70 100

100

If a person has an arterial blood pressure of 135/90 and a heart rate of 70 beats per minute, their mean arterial pressure would be approximately 225 mm Hg 135 mm Hg 105 mm Hg 90 mm Hg 45 mm Hg

105

The kidneys are continuously producing urine, however the bladder is able to effectively store urine and we eliminate it intermittently. Which of the following is responsible for the contraction of bladder muscle to cause urination? A spinal reflex that decreases smooth muscle tone of the bladder Increased levels of ADH make the bladder more permeable to fluid Sympathetic innervation of the external urethral sphincter A parasympathetic reflex that causes the bladder smooth muscle to contract Increased activity of the sodium / potassium pump

A parasympathetic reflex that causes the bladder smooth muscle to contract

What is a motor unit? All of the muscle fibers in a muscle fascicle. All of the myofibrils in the muscle fiber. A somatic motor neuron and all of the muscle fibers it innervates. A muscle fiber and all of the somatic motor neurons that innervate it. A muscle fiber and the one motor neuron that innervates it

A somatic motor neuron and all of the muscle fibers it innervates.

Why doesn't the absolute refractory period prevent sustained muscle contraction? Muscle action potentials don't depend on sodium channel activation or inactivation High levels of intracellular calcium prevent sodium channels from becoming inactivated A twitch contraction outlasts the muscle AP T-tubules function to limit the length of the absolute refractory period The absolute refractory period DOES prevent sustained muscle contractions

A twitch contraction outlasts the muscle AP

A scientist is recording action potentials in a sympathetic postganglionic neuron in an anesthetized rat and notes that the neuron is generating action potentials at a rate of approximately one per second. She then artificially stimulates a specific site in the thoracic spinal cord using a stimulating electrode and notes that the rate of action potential generation in the postganglionic she is recording from increases to approximately 10 per second. This could be because: More acetylcholine being released from specific axon terminals synapsing on the postganglionic neuron More axon terminals that synapse on that postganglionic neuron releasing their neurotransmitter Both A and B Stimulating the spinal cord would signal the pituitary gland to secrete ganglion stimulating hormone None of the above; stimulating the thoracic spinal cord would not increase the rate of action potential generation of a sympathetic postganglionic neuron

Answer Both A and B

Compared to a standard physiological solution, a 400 mOsm solution of a synthetic small protein (e.g., a twenty amino acid peptide chain) is: isotonic (and not B or C) hypertonic (and not A or C) hyperosmotic (and not A or B) A and C B and C

B and C

In the lab, you are recording from a neuron that is receiving numerous EPSPs and a few IPSPs. However, this neuron rarely fires an action potential. What might be the cause of this? The EPSPs are larger amplitude than the IPSPs The IPSPs are larger amplitude than the EPSPs The EPSPs are from inputs farther from the AP trigger zone. A and C B and C

B and C

If GFR is 125 ml/min, which of the following substances, each of which is freely filtered, is secreted, or reabsorbed? substance A: clearance rate = 250 ml/min substance B: clearance rate = 125 ml/min substance C: clearance rate = 0 ml/min substance D: clearance rate = 75 ml/min A and B are secreted while C and D are reabsorbed A is reabsorbed, C and D are secreted, and there is no net reabsorption or secretion of B C and D are reabsorbed, A is secreted, and there is no net secretion or reabsorption of B A and B are secreted, D is reabsorbed, and there is no net secretion or reabsorption of C. can't be determined based on the information provided

C and D are reabsorbed, A is secreted, and there is no net secretion or reabsorption of B

Which of the following is not a need of a typical cell? Source of nutrients Source of oxygen Source of carbon dioxide Elimination of wastes such as urea Maintenance of ECF composition

CO2 source

Which correctly describes cytoplasmic calcium increase in cardiac muscle during myocyte contraction? Calcium entry through voltage-gated calcium channels triggers the release of calcium from the sarcoplasmic reticulum by acting on ryanodine receptor channels Calcium entry through voltage-gated calcium channels triggers the release of calcium from the sarcoplasmic reticulum by acting on dihydropyridine receptors. Sodium entry through voltage-gated sodium channels triggers the release of calcium from the sarcoplasmic reticulum by acting on ryanodine receptor channels. Calcium entry through voltage-gated calcium channels is sufficient to cause muscle contraction Calcium does not need to increase because cardiac muscle does not have troponin

Calcium entry through voltage-gated calcium channels triggers the release of calcium from the sarcoplasmic reticulum by acting on ryanodine receptor channels

Compared to a non-myelinated axon, a myelinated axon Has a lower threshold for generating action potentials Can generate action potentials at a higher frequency Has larger action potentials Has longer action potentials Can conduct action potentials at a faster rate

Can conduct action potentials at a faster rate

In response to a threatening stimulus (e.g., confronting a bear in the woods), which of the following would occur: Increase in secretion of cortisol caused primarily by increased epinephrine acting on the adrenal cortex Constriction of the bronchioles caused by activation of the sympathetic nerves innervating the bronchioles Constriction of arterioles in the intestine caused by increased activity of the sympathetic nerves innervating those arterioles Increased glycogen synthesis in muscle Increased cardiac stroke volume caused in part by decreased parasympathetic nerve activity

Constriction of arterioles in the intestine caused by increased activity of the sympathetic nerves innervating those arterioles

The internal intercostal muscles... Contract during active inspiration Contract during passive inspiration Contract during active expiration Contract during passive expiration both c and d

Contract during active expiration

Administering a large amount of bicarbonate into the blood stream of a person would: Increase the activity of peripheral and brain chemoreceptors Decrease the activity of peripheral and brain chemoreceptors Increase the activity of peripheral chemoreceptors but decrease the activity of brain chemoreceptors Decrease the activity of peripheral chemoreceptors but increase the activity of brain chemoreceptors Have no effect on peripheral and brain chemoreceptors.

Decrease the activity of peripheral chemoreceptors but increase the activity of brain chemoreceptors

A patient with emphysema has increased compliance because collagen and elastin fibers in lung are destroyed. Emphysema __________________the elastic recoil of the lungs and ________________ residual capacity. Increases, increases Increases, decreases Decreases, increases Decreases, decreases Decreases, has no effect

Decreases, increases

Stimulating just the sympathetic nerves innervating the respiratory system Increases contraction of inspiratory muscles Increases contraction of expiratory muscles Increases contraction of both inspiratory and expiratory muscles Increases contraction of inspiratory muscles and inhibits contraction of expiratory muscles Does not substantially alter contraction of either inspiratory or expiratory muscles

Does not substantially alter contraction of either inspiratory or expiratory muscles

Sarah is involved in a contest where she has to drink as much water as possible as quickly as possible (definitely not a good idea!). What happens to the osmolarity of her ECF and what happens to her cells? ECF becomes hypoosmotic, cells shrink ECF becomes hyperosmotic, cells shrink ECF becomes hypoosmotic, cells swell ECF becomes hyperosmotic, cells swell ECF doesn't change because it is always in equilibrium

ECF becomes hypoosmotic, cells swell

In an isometric contraction, the muscle generates tension/force but does not shorten. How is this possible? Sarcomeres don't shorten during an isometric contraction Elastic elements of the muscle stretch as the sarcomeres shorten Isometric contractions use less ATP, therefore don't have enough energy to shorten Calcium is sequestered before enough tension develops to shorten the muscle It's not possible, all muscle contractions result in muscle shortening.

Elastic elements of the muscle stretch as the sarcomeres shorten

Emily has a condition that allows ions and other molecules that have been filtered by her kidney to be reabsorbed back into her body from her urinary bladder. What type of tissue is likely damaged in Emily? Epithelial Muscular Connective Nervous Organismal

Epithelial

At puberty, an adolescent female body changes in both structure and function of several organ systems, primarily under the influence of changing concentrations of estrogens and other steroid hormones. How can one hormone, such as estrogen, mediate so many effects? Each cell responds in the same way when steroids bind to the cell surface. Cells metabolize steroids in different ways, producing by-products that stimulate tRNA production. Estrogen is kept away from the surface of any cells not able to bind it at the surface. Estrogen is produced in very large concentration by nearly every tissue of the body Estrogen binds to different subtypes of specific receptors inside many kinds of cells, each with different responses.

Estrogen binds to different subtypes of specific receptors inside many kinds of cells, each with different responses.

Filtered load (amount) of a any filtered substance is equal to GFR GFR/renal plasma flow rate net glomerular filtration pressure / renal plasma flow et glomerular filtration pressure X plasma concentration of the substance GFR X plasma concentration of the substance

GFR X plasma concentration of the substance

If a biochemist discovers a new molecule, which of the following pieces of data would allow her to draw the conclusion that the molecule is a steroid hormone? I. The molecule is lipid II. The molecule is derived from a series of steps beginning with III. The molecule acts at a target tissue some distance from where it is IV. The molecule uses a carrier protein when in an aqueous solution such as only I and III only I, III, and IV only II and IV only II and III I, II, III, and IV

I, II, III, and IV

Which of the following accurately describes the visceral motor system, but NOT the somatic motor system. I. Highly organized muscle endplates II. Has only ionotropic postsynaptic receptors III. all neurons have their cell bodies in the central nervous system IV. Contains neurons that release norepinephrine I,II I, II, III I, III, IV III, IV IV only

IV only

Which of the following is not a stimulus for renin secretion? Decreased aortic blood pressure Decreased renal blood pressure Increased sympathetic nerve activity Decreased sodium at the macula densa Increased plasma osmolarity

Increased plasma osmolarity

Alveolar pressure: must always be negative (lower than atmospheric pressure), or the lungs will collapse. Is always negative (lower than atmospheric pressure) during inspiration. Is typically lower than pleural pressure. Is most negative at the very end of the inspiration (no air moving) Is constant throughout the respiratory cycle.

Is always negative (lower than atmospheric pressure) during inspiration.

Which of the following statements about the blood brain barrier is true? It is formed by the tight junctions between capillary endothelial cells within the brain & spinal cord It is made of up 3 layers of protective tissue surrounding the CNS. It is formed by oligodendrocytes (glial cells) that wrap around the capillaries. All of the above None of the above

It is formed by the tight junctions between capillary endothelial cells within the brain & spinal cord

Which channels is responsible for the initialdepolarization of the neuromuscular junction? Ligand gated acetylcholine channels Metabotropic acetylcholine channels Voltage gated calcium channels Voltage gated sodium channels Both a and d

Ligand gated acetylcholine channels

The human body is mostly water. Which one of the following statements is correct? Of the approximately 40L of water in an adult human, approximately two thirds is extracellular fluid. Of the approximately 40L of water in an adult human, approximately two thirds is intracellular fluid. Of the approximately 28L of water in an adult human, approximately two thirds is intracellular fluid. Of the approximately 28L of water in an adult human, approximately two thirds is extracellular fluid. The majority of extracellular fluid is the fluid component of blood

Of the approximately 40L of water in an adult human, approximately two thirds is intracellular fluid.

What is the reason that a person with a complete upper cervical spinal transection (C1-C2 level), is unable to breathe spontaneously? Inputs from peripheral chemoreceptors cannot reach the brainstem. Outputs from the dorsal and ventral respiratory groups cannot reach respiratory motor neurons in the spinal cord. The phrenic nerves are severed. Respiratory pacemaker cells in the upper cervical spinal cord were destroyed such a person can breathe spontaneously

Outputs from the dorsal and ventral respiratory groups cannot reach respiratory motor neurons in the spinal cord.

The major reason that capillary blood pressure in the renal glomeruli is higher than in other capillary beds is because the fluid in Bowman's capsule provides back pressure the kidney has both afferent and efferent arterioles the arterioles leading into the glomeruli provide less resistance than arterioles in other capillary beds the peritubular capillaries are unusually long capillary blood pressure in the renal glomeruli is not higher than in other capillaries

the arterioles leading into the glomeruli provide less resistance than arterioles in other capillary beds

The large osmotic gradient in the renal medulla results from the ascending limb of the loop of Henle pumping sodium and being impermeable to water, whereas the descending limb does not pump sodium and is permeable to water the descending limb of the loop of Henle pumping sodium and being impermeable to water, whereas the ascending limb does not pump sodium and is permeable to water the loop of Henle being impermeable to water while still being permeable to solutes like urea the loop of Henle transporting solute but not water extensive reabsorption of solute by the proximal tubule.

the ascending limb of the loop of Henle pumping sodium and being impermeable to water, whereas the descending limb does not pump sodium and is permeable to water

The plasma concentration of antidiuretic hormone is increased by increases in plasma osmolarity because: the posterior pituitary contains osmoreceptors the brain contains osmoreceptors that influence the ADH-releasing cells the macula densa cells release ADH increases in plasma osmolarity stimulates the anterior pituitary gland to release ADH-releasing hormone. increases in osmolarity are always accompanied by decreases in blood pressure, and this is sensed by baroreceptors

the brain contains osmoreceptors that influence the ADH-releasing cells

With no antidiuretic hormone present, the collecting duct is the only segment of the nephron that is impermeable to water all segments of the nephron are impermeable to water the collecting ducts and ascending limb of the loop of Henle are impermeable to water the collecting duct and the descending limb of the loop of Henle are impermeable to water Only the proximal tubule is impermeable to water

the collecting ducts and ascending limb of the loop of Henle are impermeable to water

Calcium (Ca++), sodium (Na+), and potassium (K+) are all important for the normal function of cells. Which of the following statements concerning their relative concentrations in the interstitial fluid and the cytoplasm of typical cells is correct? the concentration of Ca++ is higher in the cytoplasm than interstitial fluid the concentration of Na+ is higher in the cytoplasm than interstitial fluid the concentration of K+ is higher in the cytoplasm than interstitial fluid the concentration of Na+ is similar in the cytoplasm and interstitial fluid more than one of the above is correct

the concentration of K+ is higher in the cytoplasm than interstitial fluid

The If current is a cation current responsible for: sustained depolarization during the action potential in ventricular myocytes the depolarizing phase of the action potential in atrial myocytes the increase in Ca++in the cytosol of ventricular myocytes the depolarizing pacemaker current in sino-atrial node cells. the rapid depolarization of the action potential in sino-atrial node cells

the depolarizing pacemaker current in sino-atrial node cells.

Curare is a drug that blocks the type of nicotinic cholinergic receptor in the somatic motor system. Thus, curare would block which of the following: the effect on the heart of stimulating the vagus nerve the effect on the heart of stimulating the thoracic spinal cord the effect on leg muscle contraction of stimulating the lumbar spinal cord. a and b a and c

the effect on leg muscle contraction of stimulating the lumbar spinal cord.

During inspiration, air moves into the alveoli because the gas pressure in the lungs is less than atmospheric pressure the volume of the lungs decreases, pushing air into the alveoli muscular contraction of all the intercostal muscles forces air into the alveoli the elastic recoil of the lungs causing them to stretch contraction of the diaphragm decreases the volume of the plural cavity

the gas pressure in the lungs is less than atmospheric pressure

According to the Starling law of the heart the heart completely empties with each beat the heart empties more completely with increased activity of the vagus nerve the heart normally pumps out all of the blood returned to it when venous pressure decreases, stroke volume increases to compensate cardiac output cannot be varied, thereby maintaining circulatory stability

the heart normally pumps out all of the blood returned to it

Bulk flow of fluid from capillaries to interstitial fluid is minimal because the capillary endothelial cells provide a barrier to fluid movement the hydrostatic pressure gradient is offset by the red blood cells holding fluid in the capillaries the hydrostatic pressure gradient is opposed by an osmotic gradient, due to the concentration of sodium in blood the hydrostatic pressure gradient is opposed by an osmotic gradient resulting from the concentration of protein in blood the hydrostatic pressure gradient from capillary to interstitial fluid is so small

the hydrostatic pressure gradient is opposed by an osmotic gradient resulting from the concentration of protein in blood

The bulk flow of fluid from capillaries to interstitial space is minimal because: the hydrostatic pressure gradient from capillary to interstitial fluid is small the hydrostatic pressure gradient is opposed by an osmotic pressure gradient, due to the high concentration of Na+ in blood the hydrostatic pressure gradient is opposed by an osmotic gradient resulting from the high concentration of protein in blood the hydrostatic pressure gradient is offset by the red blood cells holding fluid in the capillaries the capillary endothelial cells provide a barrier to fluid movement.

the hydrostatic pressure gradient is opposed by an osmotic gradient resulting from the high concentration of protein in blood

The baroreceptor reflex causes which of the following cardiovascular adjustments? the increase in blood flow to exercising muscle the maintenance of blood pressure during vasodilation of a group of arterioles the decrease in blood pressure that often accompanies standing The increase in cardiac output associated with stress the increase in heart rate associated with an increase in blood pressure

the maintenance of blood pressure during vasodilation of a group of arterioles

The baroreceptor reflex produces which of the following cardiovascular adjustments the increase in blood flow to exercising muscle the maintenance of blood pressure during vasodilation of a group of arterioles the decrease in blood pressure that often accompanies standing the increase in cardiac output associated with stress the increase in stroke volume in response to increased ventricular filling

the maintenance of blood pressure during vasodilation of a group of arterioles

The relative refractory period of the neuronal action potential is due to: the inactivation (blockade) of voltage-gated Na+ channels the inability of voltage-gated K+ channels to open a ligand binding to Na+ channels the membrane potential being closer to the equilibrium potential for K+ than under normal resting conditions opening of Cl- channels

the membrane potential being closer to the equilibrium potential for K+ than under normal resting conditions

Changing the extracellular fluid concentration of K+from the normal value to 0.1 millimolar would have what effect on the resting membrane potential of a typical neuron? the membrane would become more polarized (i.e., hyperpolarized) the membrane would become less polarized (i.e., depolarized) the membrane potential would not change depends on whether the neuron is an efferent neuron or an afferent neuron the effect on membrane potential cannot be determined based on the information

the membrane would become more polarized (i.e., hyperpolarized)

Which of the following statements regarding comparison between the pulmonary circulation and systemic circulation is correct? the pressures in the 2 systems are different, however, the volume flowing through each per unit time is equal arterial pressure is higher in the pulmonary circulation the valve between the ventricle and artery opens sooner on the pulmonary side of the circulation the right ventricle muscle is stronger than the left ventricle muscle pulmonary arteriolar resistance is higher than systemic arteriolar resistance

the pressures in the 2 systems are different, however, the volume flowing through each per unit time is equal

If a nerve cell was placed in a dish and bathed with an artificial solution that was the same as normal interstitial fluid except that the calcium was removed, communication of that neuron with the neurons it innervates would fail because in the absence of extracellular calcium: K+ would leave the neuron, rendering it incapable of depolarizing to threshold sufficiently large graded potentials could not be generated even with graded potentials exceeding the normal threshold for an action potential an action potential could not be generated the process of neurotransmitter release from the nerve terminal is disrupted the nerve terminal cannot depolarize

the process of neurotransmitter release from the nerve terminal is disrupted

Blood pressure at the beginning of capillaries is typically approximately 30 mm Hg whereas it is only approximately 15 mm Hg at the distal end of the capillary. This change in pressure is the result of: diffusion of organic solutes out of the blood stream the bulk flow of fluid out of the blood stream the resistance provided by the small diameter of the capillary the lack of elasticity of capillaries capillary sphincters

the resistance provided by the small diameter of the capillary

The proximal tubule is the site at which the majority of amino acids are reabsorbed the site at which antidiuretic hormone acts to influence water reabsorption the primary site at which sodium reabsorption is regulated the site at which inulin is secreted into the tubules the site of the macula densa cells

the site at which the majority of amino acids are reabsorbed

The speed of contraction is different between slow oxidative muscle fibers and fast oxidative muscle fibers because ______ the slow fibers have less ATP the slow fibers have less creatine phosphate the slow fibers have myosin that cleaves ATP at a slower rate the slow fibers conduct action potentials slower the speed of contraction is not different between slow oxidative fibers and fast oxidative fibers

the slow fibers have myosin that cleaves ATP at a slower rate

Why might malnutrition (starvation) cause edema? interstitial protein levels are lower than plasma protein levels. the resulting anemia increases blood pressure there are not enough nutrients for plasma protein synthesis break down of muscle increases the plasma protein concentration All of the answers are correct.

there are not enough nutrients for plasma protein synthesis

During contraction of a skeletal muscle fiber the contractile proteins contract thin filaments slide toward the A band the thick filaments become tightly coiled the I band slides between the A band the lateral sacs of the sarcoplasmic reticulum shrink, pulling the Z discs together.

thin filaments slide toward the A band

The role of the "skeletal muscle pump" in the circulation is To prevent excess blood flow to non-active skeletal muscle to provide the driving force of blood flow during diastole to help force blood through the veins back to the heart to help pump additional blood into active skeletal muscle the skeletal muscle pump is not involved in the circulation

to help force blood through the veins back to the heart

Regarding tropomyosin in skeletal muscle sarcomeres: tropomyosin is the primary protein of the M line tropomyosin is found primarily in the H zone tropomyosin is found only in the I band tropomyosin is found in both the I band and the A band tropomyosin is not found in sarcomeres in skeletal muscle

tropomyosin is found in both the I band and the A band

Which of the following is NOT secreted by cells of the stomach in response to parasympathetic nervous system stimulation? pepsinogen HCl gastrin histamine trypsinogen

trypsinogen

Which of the following substances would NOT be found in secretions that pass through the sphincter of Oddi into the duodenum (i.e., first part of small intestine)? bile salts amylase pepsinogen Cholesterol Trypsinogen

trypsinogen

A portal circulation is a) a unique circulatory system allowing two tissues to exchange molecules with each other e) the passageway through which cerebrospinal fluid flows b) the unique blood supply of the brain protecting it from harmful substances in the blood c) a passageway through which a hormone enters the blood d) two groups of capillaries connected in series, allowing high concentrations of molecules released into the first set of capillaries to reach the second set of capillaries in higher concentration than reaches other tissues

two groups of capillaries connected in series, allowing high concentrations of molecules released into the first set of capillaries to reach the second set of capillaries in higher concentration than reaches other tissues

Secondary active transport of a solute (e.g., an amino acid): typically involves the transport of Na+ into the cell does not require any energy utilization by the cell cannot result in a net flux of the transported molecule across the cell membrane from a low concentration to a higher concentration is mediated by transport proteins that are themselves ATPases only transports molecules into cells

typically involves the transport of Na+ into the cell

Which of the following statements about calcium in arteriolar smooth muscle is incorrect? some of the calcium responsible for contraction comes from the extracellular fluid binding of calcium to calmodulin is important for the initiation of contraction increased cytosolic calcium, and therefore contraction, can occur in the absence of an action potential in the smooth muscle cell. paracrine signals can cause graded increases in cytosolic calcium levels under normal resting conditions, cytosolic calcium levels are so low there is no contraction

under normal resting conditions, cytosolic calcium levels are so low there is no contraction

Immediately before the onset of the T-wave of the ECG: ventricular pressure is near its minimum ventricular volume is near its minimum the valve between the left atrium and left ventricle is open the aortic valve closes the atria contract

ventricular volume is near its minimum

Sensory information regarding pressure applied to the hand enters the central nervous system via a sensory cranial nerve via a dorsal root in the cervical region of the spinal cord via a dorsal root in the lumbar region of the spinal cord via a ventral root in the cervical region of the spinal cord via a ventral root in the sacral region of the spinal cord

via a dorsal root in the cervical region of the spinal cord

Cytotoxic T cells are targeted to virus-infected cells because virus-infected cells present viral antigens along with MHC class I proteins virus-infected cells present viral antigens along with MHC class II proteins cytotoxic T cells express CD4 antibodies bind to virus-infected cells cytotoxic T cells do not destroy virus-infected cells

virus-infected cells present viral antigens along with MHC class I proteins

If a student inhales as deeply as possible and then blows the air out until he cannot exhale any more, the amount of air that he expelled is his ________________. total lung capacity inspiratory reserve capacity expiratory reserve capacity tidal volume vital capacity

vital capacity

The repolarizing phase of the neuronal action potential is due to... voltage-gated Na+ channels and voltage-gated K+ channels being open. voltage-gated Na+ channels being inactivated (blocked) and voltage-gated K+ channels being open. voltage-gated Na+ channels being open and voltage-gated K+ channels being closed voltage-gated Na+ channels and voltage-gated K+ channels being closed the Na+K+-ATPase being less active.

voltage-gated Na+ channels being inactivated (blocked) and voltage-gated K+ channels being open.

A beta-adrenergic receptor agonist applied to the heart would increase stroke volume because it would increase heart rate would increase end systolic volume would decrease end systolic volume would decrease end diastolic volume It would not alter stroke volume

would decrease end systolic volume

Dense bodies found in smooth muscle are analagous to what structure in striated muscle? A band I band H zone M line Z disc

z disc

Dense bodies in smooth muscle are most like which structure in skeletal muscle?

z line

Abnormally slow conduction through the ventricles would change the ________ in an ECG tracing T wave PR interval P wave RT interval QRS complex

QRS complex

Macula densa cells: Contribute to the filtration process in Bowman's capsule Secrete renin into blood Are the target for aldosterone Respond to changes in Na+ delivery by releasing paracrine factors Generate the high osmotic concentration in the renal medulla

Respond to changes in Na+ delivery by releasing paracrine factors

In what order are motor units recruited? Slow oxidative, fast oxidative, fast glycolytic Slow oxidative, fast glycolytic, fast oxidative Fast oxidative, slow oxidative, fast glycolytic Fast oxidative, fast glycolytic, slow oxidative A motor unit contains more than one type of fiber, so all are recruited simultaneously.

Slow oxidative, fast oxidative, fast glycolytic

If surfactant production in the lungs were to drop tremendously, what would be the effect? Surface tension in alveoli would decrease. Lung compliance would increase Small alveoli would collapse alveoli ventilation would increase pleural pressure would become positive

Small alveoli would collapse

anterior pituitary

TSH and ACTH, LH FSH and GH and prolactin

Which of the following statements about homeostasis is false? Disruption can result in illness Body temperature, nutrient supply, and fluid and ion balance are all examples The set-points can change The body compartments are in equilibrium homeostasis involves producing optimal function for the current physiological conditions

The body compartments are in equilibrium

Which of the following is false regarding the composition of blood? Hematocrit is the proportion of the blood that is comprised of red blood cells A typical hematocrit value is approximately 45% The buffy coat is made of white blood cells and makes up about 10% of the blood Plasma is yellow-tinted due to the presence of metabolites like bilirubin There are about 5 million red blood cells per microliter of blood.

The buffy coat is made of white blood cells and makes up about 10% of the blood

Oxygen diffuses from extracellular fluid into cells down its concentration gradient. As cells become more metabolically active, more oxygen is used for oxidative metabolism within the cell. Thus, which one of the following statements is correct? The concentration gradient for oxygen decreases and oxygen movement into the cell decreases. The concentration gradient for oxygen increases and oxygen movement into the cell decreases The concentration gradient for oxygen decreases and oxygen movement into the cell increases The concentration gradient for oxygen increases and oxygen movement into the cell increases The concentration gradient for oxygen does not change and therefore oxygen movement into the cell does not change

The concentration gradient for oxygen increases and oxygen movement into the cell increases

In a person with anemia (as compared to a healthy non-anemic person): PO2 of the arterial blood is reduced. PO2 of the arterial blood is increased. The percent saturation of hemoglobin is reduced The oxygen carrying capacity of blood is reduced. PCO2 of the arterial blood is increased.

The oxygen carrying capacity of blood is reduced.

Spinal muscular atrophy is the most common genetic cause of infant mortality. This is in part due to the mutation in the genes for synaptotagmin-1 (SYT1) and synaptotagmin-2 (SYT2), inhibiting their function. What is the most likely mechanism disrupting neurotransmission in patients with these mutations? They are unable to break down neurotransmitters once they've been released into the synapse. There is a reduced ability to detect calcium once it enters. Action potentials are generated but are not able to propagate to the axon terminal. The SNARE complex is unable to "dock" vesicles at the presynaptic membrane Calcium influx through voltage-gated calcium channels is inhibited.

There is a reduced ability to detect calcium once it enters.

There is a mutation that prevents the insertion of the Na+/K+ ATPase into the basolateral membrane of epithelial cells. What effect will this mutation have on glucose absorption? There would be less secondary transport of glucose across the apical membrane Transporters involved in facilitated diffusion would no longer be able to function High intracellular concentrations of glucose would saturate the glutamate transporter Glucose could be moved across the apical membrane but not the basolateral membrane Both a and b

There would be less secondary transport of glucose across the apical membrane

Why do lipophobic signaling molecules bind exclusively to membrane-bound receptors. a) Lipophobic signaling molecules are not in high enough concentration to diffuse across the membrane b) Binding proteins that carry the molecules prevent their entry into the cell c) These molecules are not potent enough to influence gene transcription d) They cannot diffuse across the membrane to reach cytosolic receptors e) all of the above

They cannot diffuse across the membrane to reach cytosolic receptors

Which of the following is an example of feed forward signaling? During childbirth, uterine contractions push the baby against the cervix. This pressure stimulates the release of a hormone, oxytocin, that triggers stronger uterine contractions. This cycle continues until the baby is born. When a person stands up, blood pressure decreases due to blood pooling in the feet and legs. The heart and blood vessels respond in such a way as to bring blood pressure back toward normal. When a person smells good food, his mouth waters due to the production of saliva. The saliva will help digest the food once it has been consumed. Both A and C Both B and C

When a person smells good food, his mouth waters due to the production of saliva. The saliva will help digest the food once it has been consumed.

Which of the following is FALSE for metabotropic receptors? a) They signal through second messenger signaling cascades. b) Signaling is slower than through ionotropic (ligand-gated) receptors c) They can be used for signal amplification d) When the ligand binds, a conformational change allows the permeable ions to flow through the pore e) All of the above are true

When the ligand binds, a conformational change allows the permeable ions to flow through the pore

Which of the following statements concerning cardiac pacemaker cells is correct? Pacemaker cells are located only in the SA node. Pacemaker cells are located in clusters spread throughout the atria and ventricles Pacemaker cells require external inputs in order to generate an action potential Within a group of pacemaker cells, all cells are electrically coupled via gap junctions Cardiac pacemaker cells exist in the brain stem, not in the heart.

Within a group of pacemaker cells, all cells are electrically coupled via gap junctions

Compared to a standard physiological solution, a 150 millimolar solution of NaCl is: isotonic isoosmolar hypoosmotic A and B A and C

a and b

During the cross-bridge cycle in skeletal muscle the cross bridge is energized as myosin ATPase activity hydrolyzes ATP the myosin cross bridge is able to bind with an actin molecule when Ca pulls the troponin-tropomyosin complex aside the linkage between actin and myosin is broken at the end of the cross-bridge cycle as Mg++ binds to the cross bridge both a and b are correct a, b, and c are all correct

a and b

When during a cardiac cycle are all 4 valves of the heart closed? isovolumetric contraction phase isovolumetric relaxation phase systolic ejection phase passive filling phase both a and b

a and b

Generation of an action potential in a specific neuron causes a 4 millivolt depolarization in a portion of a dendrite of a post-synaptic neuron. On another occasion, a 10 millivolt depolarization is recorded at that location. Which of the following might explain that? several action potentials being generated in a short period of time in the presynaptic neuron a larger action potential being generated in the presynaptic neuron action potentials being generated in other inputs to the post-saction potentials being generated in other inputs to the post-synaptic neuron a and b a and c

a and c

Which of the following conditions would produce edema? an increase in arteriolar resistance a decrease in capillary blood pressure a decrease in plasma protein concentration an increase in plasma protein concentration a decrease in diastolic blood pressure

a decrease in plasma protein concentration

Which of the following would increase the net filtration pressure in the renal glomerulus? a decrease in plasma protein concentration an increase in Bowman's capsule fluid pressure an increase in afferent arteriole constriction a decrease in efferent arteriole constriction ore than one of the above.

a decrease in plasma protein concentration

Which of the following factors would not affect the percent saturation of hemoglobin in arterial blood when alveolar PO2 is ~70 mm Hg: a decrease in pH of the blood. temperature of the blood. an increase in pH of the blood. an increase in interstitial fluid surrounding the alveoli a decrease in the number of red blood cells

a decrease in the number of red blood cells

In response to a severe decrease in blood pressure, which of the following responses will NOT occur a reflexive increase in heart rate an increase in renin secretion by the juxtaglomerular cells an increase in sympathetic nerve activity a decrease in intestinal blood flow a dilation of the veins

a dilation of the veins

An excitatory postsynaptic potential (EPSP) could be elicited in a dendrite by which of the following: a neurotransmitter causing the opening of ligand-gated Na+ channels a neurotransmitter causing the opening of ligand-gated K+ channels a neurotransmitter causing the opening of ligand-gated chloride channels a neurotransmitter acting on a G-protein coupled receptor, with the G-protein then decreasing the opening of Na+ channels none of the above; EPSPs cannot occur in dendrites

a neurotransmitter causing the opening of ligand-gated Na+ channels

Which of the following statements concerning blood volume is correct? a normal blood volume is approximately 5L, of which most is present in the capillaries a normal blood volume is approximately 5L, of which most is found in the veins the normal blood volume is approximately 3 L, of which most is found in the veins a normal blood volume is approximately 10 L, of which most is present in the arteries none of the above

a normal blood volume is approximately 5L, of which most is found in the veins

If a typical mammalian epithelial cell is placed in a solution of 150 mM NaCl containing 100 mM urea (lipid soluble), which statement about the movement of water is correct? a) There will be no net movement of water in this case. b) Water will move out of the cell by simple diffusion. c) Water will move into the cell by simple diffusion. d) Water will move out of the cell by facilitated diffusion e) Water will move into the cell by facilitated diffusion

a) There will be no net movement of water in this case.

Which of the following is incorrect? (ignore the few exceptions to the general statements) acetylcholine is the transmitter used by sympathetic preganglionic neurons acetylcholine is the transmitter used by parasympathetic preganglionic neurons acetylcholine is the transmitter used by sympathetic postganglionic neurons acetylcholine is the transmitter used by parasympathetic postganglionic neurons acetylcholine is the transmitter used by somatic motor neurons

acetylcholine is the transmitter used by sympathetic postganglionic neurons

When an action potential is generated in a somatic motor neuron, the neurotransmitter ____ is released at the neuromuscular junction, and it acts on __ receptors. Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a norepinephrine, beta adrenergic b norepinephrine, alpha adrenergic c acetylcholine, adrenergic d acetylcholine, nicotinic cholinergic e acetylcholine, muscarinic cholinergic

acetylcholine, nicotinic cholinergic e

The type of adrenergic receptors on the renin-secreting cells of the kidney are Beta-1 adrenergic receptors. Therefore, these cells would respond to activation of the sympathetic nervous system input to these cells and/or activation of the adrenal medulla activation of the sympathetic nervous system input to these cells but not activation of the adrenal medulla activation of the adrenal medulla but not activation of the sympathetic nervous system input to these cells activation of either the sympathetic nervous system input to these cells or activation of the adrenal medulla, but not at the same time neither activation of the sympathetic nervous system input to these cells or activation of the adrenal medulla

activation of the sympathetic nervous system input to these cells and/or activation of the adrenal medulla

Parathyroid hormone is released from the parathyroid gland under the control of the anterior pituitary gland is released from the parathyroid gland under the control of the posterior pituitary acts on bone and kidney to regulate blood concentration of Ca++ is a steroid hormone is an iodine-containing hormone released by the thyroid gland

acts on bone and kidney to regulate blood concentration of Ca++

Which of the following statements regarding aldosterone is FALSE: aldosterone is a steroid hormone aldosterone is secreted by cells in the adrenal cortex aldosterone contributes to Na+ and K+ homeostasis aldosterone is synthesized from cholesterol aldosterone secretion is regulated primarily by the posterior pituitary

aldosterone secretion is regulated primarily by the posterior pituitary

The rate of mediated transport is affected by a) The affinity of the molecule for the transporter B)The number of transporters found on the membrane c)The inherent speed with which the transporter operates D)All of the above e)none of the above

all of above

ATP is necessary for... muscle contraction muscle relaxation maintenance of the membrane potential All of the above A and c only

all of the above

Which one of the following statements about spinal nerves and cranial nerves is correct: all spinal nerves have somatic motor components, but only some cranial nerves do all spinal nerves have axons in the peripheral nervous system, but cranial nerves are entirely within the brain. all spinal and cranial nerves contain sensory and motor nerve fibers there are more cranial nerves than spinal nerves cranial nerves are just like spinal nerves except that they innervate the head

all spinal nerves have somatic motor components, but only some cranial nerves do

The role of Purkinje fibers in the heart is to connect the SA node to the AV node provide sympathetic innervation of the ventricles connect ventricular myocytes with each other allow the rapid spread of the action potential throughout the ventricles provide structural support of the valves

allow the rapid spread of the action potential throughout the ventricles

In skeletal muscle an increase in calcium concentration in the sarcoplasm initiates contraction by activating myosin ATPase activity binding to calmodulin binding to tropomyosin allowing actin and myosin to bind to each other causing an action potential

allowing actin and myosin to bind to each other

Each of the following would cause an increase in smooth muscle contraction except: an increase in myosin light chain kinase activity a decrease in myosin phosphatase activity an increase in Ca++ concentration in the cytosol an increase in Ca++ binding to troponin none; all of the above would increase smooth muscle contraction

an increase in Ca++ binding to troponin

Which of the following would not cause an increase in aldosterone secretion? an increase in plasma sodium concentration an increase in plasma potassium concentration a decrease in plasma sodium concentration a decrease in arterial blood pressure a decrease in the filtered load of sodium

an increase in plasma sodium concentration

The enzyme renin is directly responsible for the activation of which molecule? aldosterone erythropoietin angiotensin I atrial natriuretic peptide ADH

angiotensin I

What would be the daily urine volume and osmolality for a person deprived of drinking water for two days? approx. 0.5 L of urine, at a concentration of approx. 600 mOsm/L approx. 0.5L of urine, at a concentration <300 mOsm/L approx. 0.5L of urine, at a concentration >1000 mOsm/L 1 L of urine, at a concentration of 300 mOsm/L no urine would be excreted

approx. 0.5L of urine, at a concentration >1000 mOsm/L

Muscarinic cholinergic receptors: are found on skeletal muscle cells are ligand-gated sodium channels are receptors for adrenaline are found at parasympathetic neuroeffector sites both a and b

are found at parasympathetic neuroeffector sites

the MAJOR site of sympathetic control of blood flow to different tissues is at the arteries arterioles capillaries metarterioles veins

arterioles

If a skeletal muscle fiber were stretched to twice its normal resting length, the force it could generate in response to neural stimulation is less than it would be at its normal length. This is because: at the longer length it takes longer for the action potential to spread through the muscle fiber at the longer fiber length, more calcium is needed to cause the same increase in cytosolic calcium levels at the longer fiber length fewer cross bridges form at the longer fiber length, the angle of the energized myosin head is less efficient for contraction the statement is not true; stretching a muscle fiber to 1.5X its normal length would not influence the force it would generate.

at the longer fiber length fewer cross bridges form

During digestion of a meal there is increased blood flow to the intestine, brought about, at least in part, by autoregulation. This would be accompanied by a similar increase in blood flow to most other tissues a baroreceptor reflex evoked arteriolar constriction in some other tissues. a baroreceptor reflex evoked decrease in heart rate a baroceptor reflex evoked increase in cardiac output B and C B and D

b and d

Which of the following statements regarding epinephrine is FALSE: a) It is a catecholamine b) It is secreted by cells in the adrenal cortex c) It contributes to your sympathetic "fight or flight" response d) It is synthesized from Norepinephrine e) It is stored in secretory vesicles and released by exocytosis

b) It is secreted by cells in the adrenal cortex

Injection of sodium nitroprusside, a drug that acts directly on arteriolar smooth muscle cells to produce dilation of arterioles, into a patient will result in the following: baroreceptor reflex-induced increase in heart rate lengthened period of diastole, permitting more filling of the heart baroreceptor reflex-induced reduction in activity of sympathetic efferent fibers innervating smooth muscle of arterioles a baroreceptor reflex-induced increase in blood flow to the small intestine. increased

baroreceptor reflex-induced increase in heart rate

Fluid moving from the glomerular capillaries into Bowman's capsule would have to move across the capillary endothelial cell and then the _____ and then past _______ basal lamina : macula densa mesangial cell : basal lamina podocyte filtration slit : granular cell basal lamina : podocyte filtration slit podocyte filtration slit : basal lamina

basal lamina : podocyte filtration slit

The sodium-potassium ATPase transport system that plays a pivotal role in much of tubular reabsorption is located in the lumenal (apical) membrane of most tubular epithelial cells basolateral membrane of most tubular epithelial cells podocytes only the proximal tubule only in the Loop of Henle

basolateral membrane of most tubular epithelial cells

Atropine, a muscarinic acetylcholine receptor antagonist, would be expected to... block the effect that the vagus nerve has on heart rate cause arteries to dilate mimic the effect of stimulation of a somatic motor neuron on muscle contraction mimic the effect of parasympathetic nerve stimulation on contraction of the bladder block the effect of stimulation of the thoracic spinal cord on heart rate

block the effect that the vagus nerve has on heart rate

Why is diffusion not sufficient to account for movement of all substances in the body? The high temperature of the body slows down diffusion too much. Most molecules are too small to diffuse very far Diffusion is too slow for molecules to be able to travel the distances they need to reach all of our cells Many molecules are either lipophobic or too big to diffuse directly through the membrane. Both c and d

both c and d

Increased PCO2 of the arterial blood might result during which of the following situations: stress breathing through a long narrow tube decreased cardiac output breathing deeper without changing breathing rate breathing air with a reduced partial pressure of oxygen

breathing through a long narrow tube

Why might a beta-adrenergic receptor antagonist (beta blocker) be useful in the treatment of hypertension (high blood pressure)? by blocking beta-adrenergic receptors in arterioles it would reduce total peripheral resistance by blocking beta-adrenergic receptors in the heart it would reduce cardiac output by blocking beta-adrenergic receptors it would also reduce alpha-adrenergic receptor mediated constriction of arterioles by causing veins to constrict it would decrease cardiac output beta-adrenergic receptor antagonists cause the release of vasodilating hormones

by blocking beta-adrenergic receptors in the heart it would reduce cardiac output

A drug used in the treatment of chronic obstructive pulmonary disease (COPD), tiotropium (Spiriva) inhibits a specific class of muscarinic cholinergic receptors. This would be useful in the treatment of COPD because: by blocking parasympathetic input to the bronchioles, it would cause them to dilate by blocking sympathetic input to the bronchioles, it would cause them to dilate it would decrease the force of contraction of the internal intercostal muscles it would decrease the rate of surfactant production it would dilate pulmonary capillaries

by blocking parasympathetic input to the bronchioles, it would cause them to dilate

The action potential traveling along the t-tubule in skeletal muscle results in an increase in Ca++ levels in the sarcoplasm by opening Ca++ channels in the t-tubule membrane by activating the dihydropyridine (DHP) receptor to transport Ca++ across the t-tubule membrane by changing the conformation of the dihydropyridine (DHP) receptor resulting in a change of the ryanodine receptor resulting in an increase in Ca++ release from the sarcoplasmic reticulum by activating the Ca++ pump to pump Ca++ out of the sarcoplasmic reticulum. none of the above; action potentials don't travel along the t-tubule.

by changing the conformation of the dihydropyridine (DHP) receptor resulting in a change of the ryanodine receptor resulting in an increase in Ca++ release from the sarcoplasmic reticulum

You are testing the diffusion rate of a molecule by applying it outside a cell and measuring how much crosses into the cell over time. In which situation would the diffusion rate increase? a) You apply a smaller amount of the molecule b) You conjugate (attach) it to another known, larger protein c) You test it on a larger human cell rather than a smaller mouse cell d) You put a charge on the molecule e) None of the above, diffusion is constant

c) You test it on a larger human cell rather than a smaller mouse cell

Which one of the following is the correct sequence of a negative feedback reflex pathway? a) stimulus, receptor, output pathway, integrating center, input pathway, effector b) stimulus, effector, output pathway, integrating center, input pathway, receptor c) stimulus, receptor, input pathway, integrating center, output pathway, effector d) stimulus, effector, input pathway, integrating center, output pathway, receptor E) effector, output, integrating center, input pathway, receptor, stimulus

c) stimulus, receptor, input pathway, integrating center, output pathway, effector

In the presence of high circulating levels of ADH, what changes occur in the collecting duct? aquaporin 2 is removed from the membrane and placed into vesicles cAMP signaling results in insertion of water pores in the apical membrane gene transcription of aquaporins is turned on by ADH receptors renin secretion is stimulated the sympathetic nervous system is stimulated to cause vasodilation of the peritubular capillaries

cAMP signaling results in insertion of water pores in the apical membrane

A drug that blocks calcium channels might lower blood pressure because: the skeletal muscle pump would no longer be active the baroreceptor reflex responds to calcium calcium entering vascular smooth muscle cells through calcium channels promotes contraction of vascular smooth muscle calcium entering vascular smooth muscle cells through calcium channels promotes dilation of vascular smooth muscle. blocking calcium channels in capillary endothelial cells would cause them to swell.

calcium entering vascular smooth muscle cells through calcium channels promotes contraction of vascular smooth muscle

Tetanic contraction of the left ventricle... can be produced by intense electrical stimulation of the vagus nerve can be produced by intense electrical stimulation of the sympathetic nerves innervating the ventricles can be produced by intense electrical stimulation of the Purkinje fibers can never be produced because the pacemaker cells do not have voltage gated Na+ channels can never be produced because the left ventricle has a refractory period that lasts approximately as long as contraction

can never be produced because the left ventricle has a refractory period that lasts approximately as long as contraction

Which of the following statements regarding tubular reabsorption is correct? Tubular reabsorption: refers to the movement of a substance from the peritubular capillary blood to tubular fluid refers to the movement of substances out of Bowman's capsule can occur by active or passive transport mechanisms the majority occurs in the collecting ducts occurs only in the proximal tubule

can occur by active or passive transport mechanisms

The velocity of blood flow is slowest in arterioles, because they impose the greatest resistance capillaries, because they have the smallest diameter capillaries, because together, capillaries account for the greatest cross-sectional area veins, because pressure is the lowest the velocity of blood flow is the same throughout all levels of the circulation

capillaries, because together, capillaries account for the greatest cross-sectional area

Of the following structures in the central nervous system, which would be least involved in the control of the cardiovascular system: hypothalamus cerebellum medulla oblongata thoracic spinal cord limbic system

cerebellum

Which of the following statements regarding intercellular signaling molecules is correct? a specific molecule (e.g., histamine) can only be either a hormone, paracrine, or neurotransmitter a unique feature of hormones is that they act on all cells in the body peptides act as intercellular signaling molecules that act directly on the genome. certain hormones are secreted from the brain all intercellular signaling molecules act on receptor proteins embedded in the cell membrane

certain hormones are secreted from the brain

Which of the following is not a chemical structure of certain hormones catecholamine steroid peptide rotein cholesterol

cholesterol

Complement proteins can do all of the following except: act as opsonins kill cells promote inflammation attract neutrophils to an infected area complement proteins can do all of the things listed above

complement proteins can do all of the things listed above

Which is NOT an effect of stimulation of sympathetic nerves? breakdown of fat in adipose tissue constriction of certain blood vessels inhibition of gastrointestinal activity constriction of smooth muscle lining the airways increased sweating

constriction of smooth muscle lining the airways

Injection of norepinephrine into the blood would cause each of the following responses except increased heart rate constriction of blood vessels constriction of the pupil of the eye dilation of airways decreased intestinal motility

constriction of the pupil of the eye

There are similarities in the mechanisms that control smooth and skeletal muscle contraction. There are also differences. Which of the following statements concerning control of muscle contraction is true? Binding of Ca2+ to troponin triggers the process of contraction in both muscle types. Myosin ATPase enzymatic activity is identical in both muscle types. contraction in both muscle types results from actin and myosin filaments sliding past each other Myosin phosphatase is important in terminating muscle contraction in both muscle types Most of the Ca2+ that triggers contraction is derived from the sarcoplasmic reticulum in both muscle types

contraction in both muscle types results from actin and myosin filaments sliding past each other

Which of the following cells of the immune system are not phagocytic? neutrophils macrophages cytotoxic T lymphocytes dendritic cells all of these are phagocytic

cytotoxic T lymphocytes

If a chemical were injected into active muscle that caused a leftward shift in the hemoglobin-oxygen binding curve, what impact would that have on oxygen delivery to that muscle? have no effect increase it decrease it the effect would depend on arterial pO2 the effect would depend on venous pCO2

decrease it

A decrease in cardiac ejection fraction would occur with

decreased cardiac contractility

Placing a nerve cell in a solution in which the potassium ion concentration has been changed to 50 millimolar would cause what change in membrane potential (hint - think about what this would do to the gradient for potassium) hyperpolarize depolarize repolarize no change to membrane potential would cause an absolute refractory period

depolarize

At a normal resting heart rate, diastole lasts longer then systole systole lasts longer than diastole diastole and systole las the same length of time periods of ventricular systole and diastole overlap because systole and diastole vary, it is not possible to determine the answer based on the information provided

diastole lasts longer then systole

the pressure in the aorta measured just prior to ventricular ejection would be cardiac pressure pulse pressure mean arterial pressure diastolic pressure systolic pressure

diastolic

A charged organic molecule like glucose might get into a cell by any of the following mechanisms except: diffusion facilitated diffusion primary active transport secondary active transport

diffusion

protein

digested in stomach by acid and pepsin, and in small intestine by trypsin and chymotrypsin from pancrea

Placing a typical mammalian epithelial cell in a 400 milliosmolar solution, will cause the cell to Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a shrink, because water will move out of the cell b shrink, because water will move into the cell c expand, because water will move into the cell d neither shrink nor swell e either shrink, swell, or stay the same size, depending on the nature of the solute molecules

either shrink, swell, or stay the same size, depending on the nature of the solute molecules

Despite the fact that the left ventricle pumps intermittently, blood flow in capillaries is not intermittent. Which factor below contributes to this: the right ventricle pumps while the left ventricle fills the aortic valve remains at least partially open at all times the respiratory pump keeps blood flowing through capillaries during ventricular filling elastic properties of the aorta allow it maintain flow to the capillaries The question is incorrect; blood flow in capillaries is intermittent

elastic properties of the aorta allow it maintain flow to the capillaries

The lymphatic system... has heart-like pumps called lymph nodes. stores blood when circulatory demand is low. empties the lymph vessels into the veins near the clavicles. when removed causes elephantiasis regulates protein concentration in the plasma.

empties the lymph vessels into the veins near the clavicles.

Which of the following is not a steroid hormone? cortisol epinephrine aldosterone testosterone estradiol

epinephrine

In a healthy heart, the stroke volume of the right ventricle is: equal to the stroke volume of the left ventricle. less than the stroke volume of the left ventricle because less blood is delivered to the lungs than to the systemic circulation. greater than the stroke volume of the left ventricle because more blood must be delivered to the lungs than to the systemic circulation. less than the stroke volume of the left ventricle because the right atria is smaller and fills the right ventricle with less blood Stroke volume varies between right and left ventricles depending on circumstances

equal to the stroke volume of the left ventricle.

Elevated cortisol levels act on the brain to inhibit CRH secretion.

example of long loop negative feedback

Which of the following statements concerning facilitated diffusion is true: facilitated diffusion requires energy provided by the cell facilitated diffusion is how lipid-soluble molecules are able to cross a cell membrane facilitated diffusion refers to diffusion through a pore (i.e., channel) in the membrane facilitated diffusion can result in the net movement of molecules from a lower concentration to a higher concentration facilitated diffusion has a transport maximum

facilitated diffusion has a transport maximum

Stress puts increased metabolic demands on many tissues in the body, resulting in cells in those tissues metabolizing more glucose. A rapid response to stress is the secretion of cortisol, which makes glucose more readily available in the body, preventing a decrease in blood glucose levels. Thus, stressed-evoked cortisol secretion could be viewed as negative feedback regulation positive feedback regulation feed forward regulation resetting a set point afferent control

feed forward regulation

An increase in GFR would increase _____, resulting in the release of a paracrine factor from the macula densa that would _____. afferent arteriole pressure: constrict the afferent arteriole afferent arteriole pressure: increase filtrate flow flow of tubular fluid : dilate the afferent arteriole flow of tubular fluid : constrict the efferent arteriole flow of tubular fluid : constrict the afferent arteriole

flow of tubular fluid : constrict the afferent arteriole

Cells of the sino-atrial node... generate actions potentials during the QRS complex of the ECG generate action potentials that are due to the opening of voltage-gated Ca++ channels are stimulated by ventricular contraction generate only graded potentials, not action potentials have long projections called Purkinje fibers

generate action potentials that are due to the opening of voltage-gated Ca++ channels

Which of the following would occur during the post-absorptive (i.e., fasting) state? glycogen synthesis insulin secretion CCK secretion VLDL production gluconeogenesis

gluconeogenesis

Which of the following is NOT used in the body as a storage form of energy whose production is promoted by insulin? glycogen triglycerides proteins glucose all of the above are energy storage forms

glucose

Which of the following hormones is not released by the anterior pituitary gland prolactin thyroid stimulating hormone growth hormone gonadotropin releasing hormone adrenocorticotrophic hormone (ACTH)

gonadotropin releasing hormone

Immunoglobulin class G (IgG) antibodies are made of a single, large protein chain share a common structure with HDL have a constant region that is identical to antibodies of all classes have two sites for antigen binding

have two sites for antigen binding

ECG will show

heart rate the electrical signals generated by the heart the duration of ventricular diastole

Injection of a drug that blocks autonomic ganglionic transmission (e.g., hexamethonium) would have what effect on heart rate in an individual who had just finished exercising and therefore had a heart rate of 150 beats per minute? heart rate would remain at approximately 150 bpm because the drug blocks both sympathetic and parasympathetic actions heart rate would increase to over 180 bpm because the vagus slowing of the heart would be removed heart rate would decrease to approximately 100 bpm because the drug would block the predominantly sympathetic influence on the heart heart rate would decrease to approximately normal resting levels (70 bpm) because the drug blocks both sympathetic and parasympathetic actions heart rate would not change, because autoregulation in the heart is a powerful mechanism

heart rate would decrease to approximately 100 bpm because the drug would block the predominantly sympathetic influence on the heart

What effect would destroying the SA node have on heart rate in an otherwise normal person? no effect at all the heart would stop, because the SA node is the site of the pacemaker cells heart rate would increase, because this would remove the influence of the vagus nerve, leaving the sympathetic innervation of the ventricles unopposed. heart rate would decrease, because in the absence of the SA node the AV node would depolarize at a slower rate heart rate would decrease because it would take longer for damaged atria to fill.

heart rate would decrease, because in the absence of the SA node the AV node would depolarize at a slower rate

Respiratory acidosis could result from each of the following except: increased buildup of fluid in the lungs decreased tidal volume decreased surfactant production hyperventilation obstructive lung disease

hyperventilation

portal system is between

hypothalamus and anterior pituitary, in series capillary beds

Most carbon dioxide is transported from tissue to lungs dissolved in plasma bound to hemoglobin in red blood cells in ionic form as a solute in plasma bound to a plasma protein in white blood cells

in ionic form as a solute in plasma

During the absolute refractory period of a neuronal action potential, voltage-gated Na+ channels are ___________ and voltage-gated K+ channels are ___________________. inactivated, inactivated inactivated, open open, closed open, open open, inactivated

inactivated, open

A 10% increase in the level of CO2 in systemic arterial blood will decrease the rate of breathing increase the rate of breathing decrease pulmonary ventilation decrease alveolar ventilation decrease tidal volume

incr breathing rate

what effect would decreasing plasma protein concentration have on the flow of fluid in lymphatic vessels? increase it decrease it have no effect on it the answer would depend on specifically which proteins were decreasing.

increase

Increased constriction (by approximately 20%) of the efferent arteriole would decrease GFR and renal plasma flow increase GFR and renal plasma flow increase GFR but decrease renal plasma flow decrease GFR but increase renal plasma flow the efferent arteriole cannot constrict; only the afferent arteriole can

increase GFR but decrease renal plasma flow

administration of a beta-adrenergic receptor agonist to a person would have each of the following effects EXCEPT: Increase heart rate Increase stroke volume increase renin secretion increase insulin secretion decrease airway resistance

increase insulin secretion

At a normal resting heart rate, atropine, a drug that is a muscarinic receptor antagonist, would have what effect on heart rate? increase it decrease it not alter it, because heart rate is determined by activity of the SA node not alter it, because it would block both the parasympathetic and sympathetic influences on the heart.

increase it

Constriction of the efferent arterioles of the renal glomeruli would have what impact on GFR? increase it decrease it not change it either increase it or decrease it depending upon the conditions at the time it occurred. the efferent arterioles cannot constrict

increase it

Removing the adrenal glands would have what effect on interstitial fluid concentration of K+ over the course of several days? increase it because of changes in plasma aldosterone levels decrease it because of changes in plasma aldosterone levels increase it because of changes in plasma ADH levels decrease it because of changes in plasma ADH levels have no effect on it

increase it because of changes in plasma aldosterone levels

A decrease in the elasticity of arteries would increase diastolic pressure decrease systolic pressure increase pulse pressure increase mean arterial pressure have no effect on the pressure in the arteries

increase pulse pressure

Stimulation of the vagus nerve would... increase the duration of ventricular systole with no change in the duration of diastole decrease the duration of ventricle diastole with no change in the duration of systole increase the duration of ventricular diastole with no change in the duration of systole increase in the duration of ventricular diastole and decrease in ventricular systole increase in the duration of the ventricular diastole and systole

increase the duration of ventricular diastole with no change in the duration of systole

Each of the following would increase cardiac output EXCEPT: increased beta-adrenergic stimulation of cardiac myocytes increased beta-adrenergic stimulation of SA node cells increased alpha-adrenergic stimulation of veins increased beta-adrenergic stimulation of the papillary muscles decreased muscarinic cholinergic stimulation of the SA node

increased beta-adrenergic stimulation of the papillary muscles

Which of the following is an example of active hyperemia? baroreceptor reflex compensation of a decrease in arterial blood pressure stimulation of erythropoietin secretion at high altitude maintenance of blood flow to the brain during physical exercise increased blood flow to leg muscles during running vasoconstriction of arterioles in the legs upon standing

increased blood flow to leg muscles during running

Each of the following factors would influence total peripheral resistance EXCEPT: a large increase in hematocrit a decrease in the resistance of some arterioles atherosclerosis, causing a narrowing of some arterioles the growth of new blood vessels increased cardiac contractility

increased cardiac contractility

Which of the following responses that occur during stress is not mediated, at least in part, by the autonomic nervous system increased cardiac output decreased blood flow to the skin increased glucose mobilization from tissue increased respiratory tidal volume dilation of the pupil (eye)

increased respiratory tidal volume

Which of the following statements about hemoglobin binding to O2 is correct? increasing the metabolic activity of tissues increases the percent saturation of hemoglobin in venous blood. increasing the metabolic activity of tissues increases the percent saturation of hemoglobin in arterial blood increasing the metabolic activity of tissues decreases the percent saturation of hemoglobin in venous blood increasing the metabolic activity of tissues decreases the percent saturation of hemoglobin in arterial blood increasing the metabolic activity of tissues would have no impact on the percent saturation of hemoglobin anywhere

increasing the metabolic activity of tissues decreases the percent saturation of hemoglobin in venous blood

Most of the fluid in the body is found in Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a inside cells b in tissue surrounding the cells c in the blood stream d in the lymphatic system e inside the gastrointestinal tract

inside cells

In resting skeletal muscle, the cross bridge cycle is stopped because myosin is not in its phosphorylated active state is stopped because at the very low levels of intracellular calcium myosin is prevented from fully binding to actin is stopped because at the very low levels of intracellular calcium ATPase activity is inhibited is stopped because in the absence of depolarization, the actin molecules cannot move is still cycling, but is dissociated from contraction

is stopped because at the very low levels of intracellular calcium myosin is prevented from fully binding to actin

During this phase of the cardiac cycle, pressure inside the right ventricle increases until it becomes equal to the pressure inside the pulmonary artery.

isovolumetric contraction

Which of the following statements regarding the left A-V (or mitral) valve is true: at a ventricular pressure of 120 mm Hg, the valve would be open its closing is due to the contraction of papillary muscles connected to it it closes at approximately the time of the P wave of the ECG it closes just after the onset of ventricular contraction it is open at the same time as the pulmonary valve, allowing blood pushed into the pulmonary circulation to return to the heart

it closes just after the onset of ventricular contraction

njection of an alpha-adrenergic agonist (phenyleprhine is such a drug) increases blood pressure because it increases stroke volume it increases heart rate it decreases the elasticity of arteries it increases blood flow it decreases the radius of arterioles

it decreases the radius of arterioles

A large increase in cardiac filling pressure results in an increase in Na+ excretion because it stimulates ADH secretion it produces a reflexive increase in sympathetic neural activity to the kidney it increases arterial pressure which therefore increases GFR it decreases the sympathetic neural activity to the adrenal cortex it stimulates the secretion of atrial natriuretic hormone (also called atrial natriuretic peptide)

it stimulates the secretion of atrial natriuretic hormone (also called atrial natriuretic peptide)

Which of the following statements about the Na+-K+ATPase is incorrect? it is electrogenic (i.e., it generates an electrical gradient across the membrane with each transport cycle it transports 3 Na+ and 2K+ it transports K+ out of the cell, but Na+ into the cell it is a primary active transport protein it establishes the Na+ gradient that drives most secondary active transport

it transports K+ out of the cell, but Na+ into the cell

The major determinant of the number of red blood cells is a hormone, released from the ____________, in response to ____________. bone marrow, oxygen delivery heart, glucose delivery kidney, low arterial pressure kidney, decreased glucose delivery kidney, decreased oxygen delivery

kidney, decreased oxygen delivery

Which of the following is most likely to be observed in a patient with respiratory alkalosis that has been compensated for by the kidneys over the long term? body retains less carbon dioxide kidneys conserve bicarbonate kidneys secrete fewer hydrogen ions respiratory rate increases tidal volume increases

kidneys secrete fewer hydrogen ions

If the pressure in the intrapleural space became equal to that in the alveoli, then what would happen? the lungs would collapse air would move into the lungs the alveoli would enlarge the lungs would expand breathing would continue normally

lungs collapse

An important difference between simple diffusion and mediated transport is that Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a ions can only get across a cell membrane by mediated transport b mediated transport, but not simple diffusion, has a transport maximum (i.e., it can saturate). c simple diffusion can only result in net movement of molecules down a concentration gradient whereas mediated transport can only result in the net movement of molecules up a concentration gradient. d simple diffusion doesn't require external energy whereas mediated transport does. e none of the above

mediated transport, but not simple diffusion, has a transport maximum (i.e., it can saturate).

Compared to normal resting breathing, at the end of inspiration of a larger breath, intrapleural pressure would be the same more negative less negative more positive less positive

more negative

The first lumbar segment of the spinal cord contains: somatic motor neurons in the dorsal horn region motor neurons in the ventral horn region that receive direct sensory input sympathetic postganglionic neurons in the ventral horn region parasympathetic preganglionic neurons in the dorsal horn region somatic motor neurons that control the movement of fingers

motor neurons in the ventral horn region that receive direct sensory input

Which of the following statements about somatic motor neurons is FALSE: most motor neuron cell bodies are present in the ventral horn of the spinal cord motor neurons synapse in the ventral root ganglion acetylcholine is the primary neurotransmitter of motor neurons some input to motor neurons comes directly from the primary motor cortex some somatic motor neurons are located in the brain

motor neurons synapse in the ventral root ganglion

If GFR is normal and the clearance of substance X is 200 ml/min, then the substance must have been actively secreted in the nephron must have been passively secreted in the nephron must have been actively reabsorbed in the nephron must have been not filtered by the nephron the renal handling of this substance cannot be determined based on the information provided.

must have been actively secreted in the nephron

The regulation of smooth muscle contraction is mediated by the phosphorylation of ________ in response to calcium binding to ______ myosin, calmodulin actin, calmodulin troponin, calmodulin myosin, troponin actin, troponin

myosin, calmodulin

A substance used to measure glomerular filtration rate by measuring its clearance, would need to be filtered and neither reabsorbed or secreted completely reabsorbed completely secreted completely reabsorbed and completely secreted GFR cannot be determined by measuring the excretion of a substance.

neither reabsorbed or secreted

The normal rhythm of quiet breathing is generated by pacemaker potentials in the phrenic motor neurons nerve cells in the medullary region of the brain stem sensory feedback from the lungs a spinal reflex neurons in the cerebral cortex

nerve cells in the medullary region of the brain stem

Increasing the PO2 of inspired air from 160 mm Hg to 180 mm Hg would have what effect on breathing? it would decrease the rate of breathing without changing tidal volume it would decrease tidal volume without changing the rate of breathing it would decrease both the rate of breathing and tidal volume it would increase both the rate of breathing and tidal volume it would have no significant effect

no effect

Tetanic contraction of skeletal muscle would result from: a single stimulation of multiple motor neurons a larger than normal action potential in the motor neuron innervating the muscle fiber stimulation of the motor neuron innervating the muscle fiber to elicit action potentials in the neuron at the rate of 1 per second injection of a drug that stimulates muscarinic cholinergic receptors none of the above

none of the above

Placing a specific type of neuron in a hypotonic solution causes it to generate action potentials. The depolarizing potentials getting the neuron to the threshold for action potential generation most likely result from opening of a ligand-gated channel that is permeable to Na+ opening of a ligand-gated channel that is permeable to K+ opening of a mechanosensitive channel that is permeable to Na+ opening of a mechanosensitive channel that is permeable to K+ opening of a voltage-gated channel that is permeable to Na+

opening of a mechanosensitive channel that is permeable to Na+

Histamine released by mast cells does not contribute to opsonizaton of pathogens redness at the site of an infection increased capillary permeability at the site of an infection

opsonizaton of pathogens

What process is used for water reabsorption in the kidney? Osmosis Secondary active transport through symport with Na+ Primary active transport Secondary active transport through antiport with Na+ Water isn't reabsorbed in the kidney

osmosis

Histamine released by a specific cell type (mast cells) in tissue acts on nearby blood vessels to cause them to become more permeable to certain substances. This is an example of neural communication endocrine communication paracrine communcation electrical coupling a positive feedback system

paracrine communcation

found passing through the common bile duct (

pepsin and trypsin

If neural innervation of the GI tract were severed, how would peristalsis be affected? (note that the enteric nervous system would still be present) peristalsis would be absent permanently throughout the GI tract peristalsis would be absent in the stomach but present in the small intestine peristalsis would still occur in most regions of the GI tract peristalsis would be absent everywhere except the colon peristalsis would still occur in most regions of the GI tract but at a much faster rate.

peristalsis would still occur in most regions of the GI tract

The primary role of neutrophils in the immune response is to phagocytize pathogens act as opsonins stimulate antibody secretion cause inflammation

phagocytize pathogens

The anterior pituitary gland secretes hormones that influence each of the following tissues in women except: the posterior pituitary the adrenal gland the liver the thyroid gland the ovaries

posterior pituitary

Aldosterone... functions in pH regulation helps decrease blood volume is secreted in response to elevated levels of sodium in the blood increases the concentration of sodium in urine promotes sodium retention in the kidneys

promotes sodium retention in the kidneys

The cililated cells of the airways function to provide rigid support to keep the airways open produce mucus engulf foreign material that has been trapped in the mucus propel mucus toward the nose and mouth help push more air into the alveoli

propel mucus toward the nose and mouth

A scientist stimulated the sympathetic nerve innervating the heart of a cat, and, as expected, witnessed the expected effect on heart rate. She left the lab and when she later returned the same stimulus was no longer effective at influencing heart rate. When questioned, the assistant admitted to having injected some drug into the cat, but couldn't remember the name of the drug. Which one of the following drugs might it have been? atropine (a muscarinic receptor antagonist) propranolol (a beta-adrenergic receptor antagonist) muscarine (muscarinic receptor agonist) nicotine (nicotinic receptor agonist) epinephrine

propranolol (a beta-adrenergic receptor antagonist)

he T-tubules in skeletal muscle store Ca++ form the Z discs allow for nutrients to be carried into the cell store ATP provide a means of rapidly transmitting the action potential throughout the muscle fiber

provide a means of rapidly transmitting the action potential throughout the muscle fiber

The MAJOR parameter influencing changes in total peripheral resistance is blood viscosity the radius of arterioles the plasma protein concentration cardiac output blood volume

radius

The difference in the rate of contraction of "fast" and "slow" skeletal muscle fibers is due to

rate at which myosin is cleaved

The drug curare, which causes paralysis of voluntary muscle contraction is an antagonist at receptors that mediate transmission in autonomic ganglia receptors in skeletal muscle that normally respond to acetylcholine adrenergic receptors in skeletal muscle receptors that cause phosphorylation of adenylyl cyclase muscarinic cholinergic receptors

receptors in skeletal muscle that normally respond to acetylcholine

Active hyperemia refers to the arteriolar dilation that occurs within a tissue in response to local chemical changes that accompany increased metabolic activity in that tissue refers to local arteriolar mechanisms that are aimed at keeping tissue blood flow constant in spite of deviations in arterial pressure refers to the increase in blood flow to tissue that accompanies increases in cardiac output is important in maintaining an adequate pressure to drive blood through the body is an example of extrinsic control of regional blood flow

refers to the arteriolar dilation that occurs within a tissue in response to local chemical changes that accompany increased metabolic activity in that tissue

Which of the following statements regarding average capillary hydrostatic pressure is correct: renal glomerulus > pulmonary> muscle renal glomerulus > muscle > pulmonary pulmonary> muscle > renal glomerulus muscle > renal glomerulus > pulmonary hydrostatic pressure is constant throughout the capillaries

renal glomerulus > muscle > pulmonary

secondary active transport... requires the occurrence of primary active transport does not require enery utilization by the cell cannot result in the next flux of the transported molecule up a concentration gradient only occurs in neurons and muscle cells only transports molecules into cells

requires the occurrence of primary active transport

Putting a typical mammalian cell in a solution made up of 150 millimolar valine (an amino acid), 150 millimolar NaCl, and 150 mM substance X (which is freely lipid soluble) would cause the cell to swell shrink stay to same size cannot be determined from the information provided

shrink

The skeletal muscle pump refers to: the ability of rhythmic contraction of skeletal muscle to force additional blood into that muscle skeletal muscle contraction causing the constriction of veins in that muscle skeletal muscle contraction causing vasodilation of arterioles in the muscle so it receives more blood flow the "sucking" of blood into the thoracic cavity through the contraction of respiratory muscles the fact that heart muscle works like skeletal muscle

skeletal muscle contraction causing the constriction of veins in that muscle

The large membrane depolarization that represents a neuronal action potential is due to the flux of what ion? sodium potassium calcium chloride more than one of the above

sodium

Which of the following is NOT an action or effect of the hormone CCK? contraction of the gall bladder stimulation of insulin secretion from the pancreas inhibition of gastric motility stimulation of bile secretion into the intestines all of the above are actions of CCK

stimulation of insulin secretion from the pancreas

Two stimuli to a neuron (stimulus A and stimulus B) are both above threshold (suprathreshold) and last for 1 second. However, stimulus A is a stronger stimulus. Therefore, only stimulus A will produce an action potential. the action potential produced by stimulus A will be larger than that produced by stimulus B the action potential produced by stimulus A will be of longer duration than that produced by stimulus stimulus A will cause a higher frequency of action potentials in terms of action potential generation (both magnitude and frequency), both stimuli would have the same effect.

stimulus A will cause a higher frequency of action potentials

The volume of blood ejected from each ventricle during a contraction is called the _____________________. end-systolic volume stroke volume cardiac reserve end-diastolic volume. cardiac output

stroke volume

What is the physiological outcome of the Frank-Starling (or Starling) Law of the Heart? the right and left ventricles pump the same amount of blood arterial pressure remains constant, despite arteriolar vasodilation the baroreceptor reflex adjusts cardiac output such that as aortic pressure increases the force of contraction of the heart increases to maintain cardiac output end-systolic volume changes with changes in atrial filling pressure stroke volume is equal to the volume of blood returning to the heart during diastole

stroke volume is equal to the volume of blood returning to the heart during diastole

Lung compliance is determined by elasticity of the lungs and lung volume intrapleural pressure surface tension airway resistance transpulmonary pressure

surface tension

The difference in the rate of contraction between "fast" and "slow" skeletal muscle fibers is due to the speed of the action potential the diameter of the muscle fiber the concentration of phosphocreatine the ATPase activity of the myosin the affinity of troponin for calcium

the ATPase activity of the myosin

During contraction of a slow oxidative muscle fiber, the Z line gets smaller the A band gets wider the length of the thick filaments gets shorter the I band gets smaller the dense bodies get denser

the I band gets smaller

Flow autoregulation refers to the fact that the heart automatically pumps the same amount of blood that it fills with the right and left ventricles pump the same amount of blood the negative feedback reflex that keeps cardiac output constant. the ability of arterioles to constrict or dilate in response to intrinsic factors of the tissue to keep tissue blood flow constant despite changes in arterial pressure the flow to the lungs automatically adjusts to match to flow through the systemic circulation.

the ability of arterioles to constrict or dilate in response to intrinsic factors of the tissue to keep tissue blood flow constant despite changes in arterial pressure

Flow autoregulation refers to: the ability of individual tissues to adjust their blood flow to match their need the ability of the heart to pump the amount of blood that it fills with the ability of the heart to adjust cardiac output to meet the needs of the body the ability of the baroreceptor reflex to maintain constant arterial pressure the ability of capillaries to open and close

the ability of individual tissues to adjust their blood flow to match their need

Each of the following glands secrete a steroid hormone except: the anterior pituitary gland the testes the adrenal cortex ovaries all of the above secrete steroid hormones

the anterior pituitary gland

Although the left ventricle pumps blood only intermittently, arterial blood pressure does not decrease to near zero when the left ventricle is not ejecting blood into the arteries because: the right ventricle ejects blood during that period the arterioles provide resistance to flow the arteries have elastic properties the skeletal muscle pump provides some pressure the respiratory muscle pump provides some pressure

the arteries have elastic properties