Exam 1:Quiz 1 and 2: Lecture 1-20

Question 1

What is the interstitial fluid volume (L) of a sheep weighing 77 kg? Show your work, include units in your answer, and round to one decimal place for full credit.

Answer 1

Your Answer:
77 kg x 16% of interstitial fluid

77 kg x 0.16 of I.F. = 12.32 L = 12.3 L of interstitial fluid for a 77kg sheep

Question 2

which substance is a major anion in the ICF?

Answer 2

organic phosphate

Question 3

which transporter indirectly uses energy by using the Na+ gradient to transport gluose against its conentration gradient?

Answer 3

Na+/ glucose co-transporter (SGLT 1)

Question 4

If a cell with normal osmolarity is placed into an extracellular solution with an osmolarity of 240 mOsm/L, where will water move via osmosis?

Answer 4

water will move from the extracellular solution into the cell

Question 5

How would a solution of 270 mOsm/L be described when compared to a solution of 250 mOsm/L?

Answer 5

hyperosmotic

Question 6

Solution A has an osmolarity of 245 mOsm/L and Solution B has an osmolarity of 230 mOsm/L. Which solution has greater osmotic pressure?

Answer 6

solution A

Question 7

Which ion is most commonly responsible for depolarizing the membrane potential?

Answer 7

Na+

Question 8

Which event(s) is/are associated with repolarization? More than one may be correct.

• closing of Na+ inactivation gates
• opening of Na+ activation gates
• opening of K+ channels
• closing of K+ channels

Answer 8

closing of Na+ inactivation gates

opening of K+ channels

Question 9

Which characteristic would allow an action potential to propagate the farthest?

Answer 9

internal resistance low

Question 10

Which neurotransmitter is considered to be inhibitory?

Answer 10

glycine

Question 11

Which neurotransmitter is excitatory and can use either ionotropic or metabotropic receptors?

Answer 11

glutamate

Question 12

What is the second messenger that, along with calcium, will activate protein kinase C in the phospholipase C system?

Answer 12

DAG

Question 13

Which type of axon would carry motor signals to skeletal muscle?

Answer 13

somatic efferent

Question 14

Which area of the CNS is the “intermediate” in receiving sensory information to pass on to the cerebrum?

Answer 14

brainstem

Question 15

Which major division of the CNS contains the hypothalamus, which is involved in regulation of hormone secretion from the pituitary gland?

Answer 15

forebrain

Question 16

All preganglionic neurons in the autonomic nervous system release what neurotransmitter

Answer 16

Acetylcholine

Question 17

Where are the cell bodies of PSNS preganglionic neurons located?

Answer 17

brainstem or spinal cord

Question 18

Which adrenergic receptor will cause relaxation of smooth muscle when stimulated?

Answer 18

beta 2

Question 19

Which adrenergic receptor causes inhibition of neurotransmitter release from the presynaptic terminal?

Answer 19

Alpha 2

Question 20

Which receptor(s) is/are stimulatory in the PSNS and use the phospholipase C signaling pathway?

Answer 20

M1, M3, and M5

Question 21

To which subunit of troponin does calcium bind when intracellular calcium concentration rises?

Answer 21

troponin C

Question 22

Within the myofibril, where does the force of contraction develop?

Answer 22

A band

Question 23

How does extracellular calcium enter cardiac cells during a muscle contraction?

Answer 23

L-type calcium channels

Question 24

Which structure(s) replace(s) sarcomeres in smooth muscle?

Answer 24

dense bodies

Question 25

Which enzyme changes myosin head conformation to allow it to bind actin in smooth muscle?

Answer 25

myosin light-chain kinase

Question 26

Which vascular bed has the highest cross-sectional area?

Answer 26

capillaries

Question 27

what determines blood distribution to tissues

Answer 27

oxygen demand

Question 28

in which vessels does control of blood flow mainly occur

Answer 28

arterioles

Question 29

the hearts of all species are able to maintain complete seperation between oxygenated and deoxygenated blood

true / false

Answer 29

flase

Question 30

what happens to resistance in a blood vessel as radius of the vessel increases

Answer 30

decreases

Question 31

You have the following information on a patient: systolic arterial blood pressure = 120 mm Hg, diastolic arterial blood pressure = 75 mm Hg, and heart rate = 85 BPM. What is the mean arterial pressure? You must show your work and include correct units to receive full credit.

Answer 31

75 mm Hg + 1/3 (systolic BP - diastolic BP)

75 mm Hg + 1/3 ( 120 mm Hg - 75 mm Hg) = 90 mm Hg

Question 32

You have the following information on a dog: end-diastolic volume = 35 mL, end-systolic volume = 19 mL, and heart rate = 70 BPM. What is cardiac output? You must show your work and include correct units to receive full credit.

Answer 32

( end-diastolic - end-systolic) x HR = X

(35 mL - 19 mL ) x 70 BPM = 1210 mL/min

Question 33

A 440 kg horse has an end-diastolic volume of 740 mL and a stroke volume of 520 mL. What is the ejection fraction? You must show your work and include units (%) to receive full credit.

Answer 33

stroke volume / end-diastolic volume = x

520 mL / 740 mL = 0.70 x 100 = 70%

Question 34

A 20 kg lamb has an end-diastolic volume = 45 mL, end-systolic volume = 12 mL, and heart rate of 90 bpm. What is stroke volume? You must show your work and include correct units for full credit.

Answer 34

end-diastolic volume - end-systolic volume = x

45 mL - 12 mL = 33 mL

Question 35

For most species, aortic pressure averages __________________ and right atrial pressure averages ___________________.

Answer 35

80-120 mm Hg, 0-5 mm Hg

Question 36

Which ion is responsible for the upstroke in Phase 0 of a cardiac action potential?

Answer 36

sodium

Question 37

Which receptors are used by the sympathetic nervous system to increase heart rate, conduction velocity, and contractility?

Answer 37

Beta-1 receptors

Question 38

As heart rate increases, intracellular Ca concentrations increase due to more Ca entering cell and more action potentials per unit time

true or false

Answer 38

true

Question 39

Besides an increase in pressure, what else occurs during isovolumetric contraction of the left ventricle?

Answer 39

valves are closed, so volume remains constant

Question 40

When the left ventricle contracts and the mitral valve closes, this coincides with:

Answer 40

the first heart sound

Question 41

What portion of the ECG represents depolarization of the atria?

Answer 41

P wave

Question 42

What is the function of baroreceptors located in the walls of the carotid sinus and aortic arch?

Answer 42

respond quickly to keep arterial pressure constant

Question 43

During the effective refractory period, a stimulus may locally excite the tissue, but conduction of an action potential can’t occur – some Na+ channels are starting to open during this period.

true or false

Answer 43

true

Question 44

Which type of blood vessel holds the unstressed volume?

Answer 44

veins

Question 45

What is the primary force causing fluid movement (filtration) out of the capillaries?

Answer 45

coronary
cerebral
pulmonary

Question 46

If tension in the ventricular wall decreases, myocardial oxygen consumption increases.

Answer 46

false

Question 47

Based on radius, which vessels would have the greatest resistance?

Answer 47

capillaries

Question 48

Which factor would be most likely to cause fluid to move out of capillaries and into tissues?

Answer 48

high interstitial oncotic pressure

Question 49

What is the heart rate if the RR interval is 325 msec?

Answer 49

185 bpm

Question 50

If a substance has a negative ionotropic effect on the heart, what happens to contractility?

Answer 50

decrease