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Flashcards in Exam 3 Deck (50):
1

The _______________ is an intracellular storage site for calcium found in skeletal muscle.

Sarcoplasmic reticulum

2

What is the function of T tubules

The conduct action potentials from the sarcolemma to the interior of the muscle cell.

3

During skeletal muscle contraction, as the sarcomere shortens, the ______ and ______ shorten as myosin pulls actin towards the M line.

H-zone : I band

4

__________covers the binding sites for myosin on actin when a muscle fiber is relaxed.

Tropomyosin

5

In order for crossbridge cycling to occur, calcium needs to bind to ________ and ATP needs to bind to __________.

Troponin : myosin

6

Which of the following steps in excitation-contraction occurs first?

Acetylcholine is released from the motor neuron.

7

Which of the following steps in excitation-contraction occurs first?

Acetylcholine is released from the motor neuron.

8

Which of the following would allow a contracting muscle to relax?

Calcium being taken back up by the sarcoplasmic reticulum

9

When skeletal muscles utilize ___________ to regenerate ATP during intense exercise like sprinting, lactic acid is formed

Anaerobic glycolysis

10


When you do sit ups, your abdominal muscles undergo _______ muscle contraction, which creates force _______ movement.

Isotonic : with

11

A single action potential occurring on a motor neuron will cause __________ in the muscle fiber it innervates.

A twitch

12

Which of the following would increase the strength of contraction in your quadriceps?

Recruiting large motor units.

13

Which of the following characteristics would be typical of an extreme endurance athlete's leg muscle?

High myoglobin content

14

Muscle fatigue is caused by:

changes in ion concentration

depletion of acetylcholine

depletion of energy reserves

lactic acid accumulation


ALL CORRECT

15

Plasma is 90% ________, which serves as the transport medium and helps carry heat.

Water

16


_________ is the most abundant plasma protein, it is a major contributor to colloid osmotic pressure and non-specifically carries hydrophobic substances.

Albumin

17

The hormone _________that causes new red blood cell production in the bone marrow is released by the ________ in response to a reduced oxygen carrying capacity of the blood.

Erythropoietin : kidneys

18

Hemoglobin:

Is found in erythrocytes

19

________ are the least abundant type of leukocyte in the blood, and release histamine and heparin in response to parasites and allergens.

Basophils

20

B cells that produce antibodies against specific targets are ______.

Lymphocytes

21


_______ are immature macrophages circulating in blood.

Monocytes

22

Platelets

i are shed from megakaryocytes in the bone marrow in response to the liver releasing thrombopoietin.

form a plug when they come in contact with the von Willebrand factor bound to exposed collagen in damaged blood vessels.

in a platelet plug release chemical messengers like epinephrine to cause vasoconstriction.

in a platelet plug release ADP, that causes the surface of nearby circulating platelets to become sticky so that they also adhere to the en

23

Which of the following steps in hemostasis occurs last

Conversion of fibrinogen to fibrin

24

Deoxygenated blood returning to the heart from the systemic circuit enters the_________________.

Right atrium

25

Which of the following is a DIFFERENCE between cardiac muscle and skeletal muscle?

Presence of gap junctions between adjacent muscle fibers.

26

The atrioventricular valves open when

Atrial pressure is greater then ventricular pressure.

27

The depolarization or rising phase of the action potentials in AUTORHYTHMIC cells of the heart, is due to:

Opening of L-type calcium channels.

28

The depolarization or rising phase phase of the action potentials in the CONTRACTILE cells of the heart, is due to:

Opening voltage gated sodium channels

29

Which of the following of an ECG encompasses ventricular systole:

QT segment

30

The closing of the semilunar valves signals the end of

Ventricular ejection

31

The longest phase in the cardiac cycle is

Ventricular filling

32

All four heart valves are open during

None of the phases of the cardiac cycle

33

The amount of blood in the be tricked at the end of the ventricular filling is

End diastolic volume

34

The sympathetic nervous system innervates the SA node. When the sympathetic postganglionic neurons fire action potentials:

T-type channel opening is enhanced.

35

The sympathetic nervous system can INCREASE cardiac output by:

increasing venous return.

increasing heart rate.

increasing force of ventricular contraction.

increasing stroke volume.

correct all of the above

36

Which of the following would INCREASE blood flow?

An increase in blood pressure

37


________are compliant and act as volume reservoirs.

Veins

38



________act as pressure reservoirs when the ventricles relax.
correct Arteries

Arteries

39

________are the major determinant of total peripheral resistance in the vascular tree, because they can vasodilate or vasoconstrict.

Arterioles

40


______ are only one cell layer thick and are where exchange between the circulatory system and interstitial fluid takes place.

Capillaries

41



Which of the following factors would cause vasodilation of arterioles supplying a tissue?

histamine

nitric oxide

placing a heating pad on the area

increased concentration of carbon dioxide in the tissue being supplied by the arteriole


correct all of the above would cause vasodilation

42



What is the primary method by which small water soluble molecules like electrolytes are exchanged between plasma in the capillaries and interstitial fluid surrounding tissues?

Diffusion/bulk flow through pores between capillary endothelial cells.

43



At the beginning of the capillary bed ________ is the major force causing filtration, while at the end of the capillary bed _______ is the major force causing absorption.

capillary blood pressure : colloid osmotic pressure

44

The lymphatic system:

returns excess fluid filtered at the capillaries to the circulatory system.

transports fat absorbed from the small intestine.

is a low pressure circuit.

contains lymph nodes that are filled with leukocytes that help defend against pathogens.

All of these are correct

45

Veins

Contain one way valves

46

Venous return to the heart helped by:

skeletal muscle pumps.

one way valves.

cardiac suction.

venous vasoconstriction.


correct all of the above

47



When measuring blood pressure with a sphygmomanometer you record __________ the LAST time you hear any sounds through the stethoscope.

Diastolic pressure

48



If baroreceptors in your carotid sinuses detect an INCREASE in blood pressure and increase the frequency of action potentials to the cardiovascular control center in your oblongata, your cardiovascular control center will do which of the following in order to DECREASE your blood pressure?

Via the parasympathetic nervous system decrease heart rate.

49


While taking this exam your cardiac output increases as well as your total peripheral resistance. What effect would this have on your mean arterial pressure?

It would elevate your mean arterial pressure

50

Hypertension can cause:

Congestive heart failure
Stroke
Heart attack
Renal damage