Deck 9: Circulatory Systems

Question 1

Which of the following components is essential for a circulatory system?

A) fluid
B) pump-organ
C) vessels
D) cells
E) all of these

Answer 1

fluid

Question 2

The hematocrit is

A) the packed hemocytes found in hemolymph.
B) the packed red blood cells only.
C) the packed white blood cells only.
D) the total packed cell volume of blood.
E) the total volume of oxygen carried in the blood.

Answer 2

the total packed cell volume of blood.

Question 3

Plasma proteins constitute about _____ percent of plasma by weight.

A) 8- 10
B) 6 - 8
C) 4 - 6
D) 1 - 4

Answer 3

6 - 8

Question 4

The dominant inorganic cation in blood is

A) Na⁺
B) Cl^-
C) K⁺
D) HCO₃^-
E) Ca²⁺

Question 5

Antibodies are

A) $\alpha$ -globulins.
B) $\beta$ -globulins.
C) $\gamma$ -globulins.

Question 6

Which of the following does NOT contain cholesterol?

A) chylomicrons
B) high density lipoproteins
C) low density lipoproteins
D) very low density lipoproteins
E) All of these contain cholesterol.

Question 7

Both insects and vertebrates have ___________ in their circulatory fluid

A) chylomicrons
B) high density-lipoproteins
C) low-density lipoproteins
D) high-density and low-density lipoproteins
E) chylomicrons, high-density and low-density lipoproteins

Question 8

Erythrocytes function in the transport of CO₂ by

A) containing carbonic anhydrase, which catalyzes the interconversion of CO₂ and bicarbonate.
B) containing hemoglobin, which binds CO₂ to the iron portion.
C) containing hemoglobin, which binds CO₂ to the protein portion.
D) both containing carbonic anhydrase and binding CO₂ to the iron portion.
E) both containing carbonic anhydrase and binding CO₂ to the protein portion.

Question 9

In humans, old, worn out erythrocytes are destroyed in the _____ and their replacements are derived from _____ residing in the _____.

A) spleen; pluripotent stem cells; red marrow
B) spleen; embryonic stem cells; red marrow
C) red marrow; pluripotent stem cells; spleen
D) red marrow; embryonic stem cells; spleen
E) liver; pluripotent stem cells; red marrow

Question 10

Vascular spasm as a result of trauma to vessels minimizes blood loss by

A) slowing blood flow through the vessels as a consequence of constriction.
B) pressing together the surfaces of the vessel, promoting adhesion and sealing off the damaged vessel.
C) slowing blood flow as a result of sympathetic stimulation.
D) Only two of these.
E) All of these.

Question 11

ADP released by platelets is involved in reducing blood flow through an injured vessel by

A) causing the vascular musculature to remain contracted longer during the vascular spasm.
B) causing the surface of nearby endothelial cells to become sticky so that platelets will stick to them, enhancing aggregation of platelets.
C) causing the surface of nearby platelets to become sticky so that platelets will stick to them, enhancing aggregation of platelets.
D) increasing the release of fibrinogen by activated platelets.
E) all of these.

Question 12

Fibrinogen is converted to fibrin by

A) factor XIII.
B) prothrombin.
C) thrombin.
D) factor X.
E) platelet factor 3 (PF3).

Question 13

Although a grasshopper has a heart, it only functions in pumping blood when it's at rest because during activity blood is pumped by a _____ type pump.

A) flagella
B) extrinsic
C) peristaltic muscle
D) chamber muscle
E) none of these.

Question 14

In the heart of cartilaginous fishes, blood enters the _____ and is returned to the systemic circulation by the _____.

A) right atrium; left ventricle
B) sinus venosus; conus arteriosus
C) sinus arteriosus; conus venosus
D) sinus venosus; bulbus arteriosus
E) sinus arteriosus; bulbus venosus

Question 15

A significant change in vertebrate hearts began when

A) the ancestors of whales returned to the oceans.
B) flight evolved in birds.
C) reptiles moved onto land.
D) air-breathing fish evolved.
E) amphibians transitioned to life on land and in water.

Question 16

Brisket disease

A) is the development of tissue edema in cattle that have acclimatized to high altitude and then been shifted to low altitude.
B) is a disease occurring in race horses resulting in insufficient blood flow to support running.
C) occurs when the right atrium over fills as a result of circulatory edema .
D) none of these.

Question 17

Which of the following statements about the heart is true?

A) The left side of the heart is stronger than the right side.
B) The right side of the heart is stronger than the left side.
C) The left side of the heart pumps a greater volume of blood than the right side.
D) The right side of the heart pumps a greater volume of blood than the left side.
E) None of these.

Question 18

Which of the following statements is NOT true?

A) Cnidarians circulate fluid in the coelenteron.
B) The differences between an open and a closed circulatory system are clear-cut.
C) Many animals have an internal extracellular fluid that is separate from the environment.
D) The fluid leaving the capillary bed of closed circulatory systems is similar to the hemolymph of open systems.
E) Closed circulatory systems are made necessary by the large size of organisms that have them and the large distances between nutrient sources and cells.

Question 19

Which statement about desmosomes is NOT true?

A) They hold cells together under high mechanical stress.
B) They are located in intercalated discs.
C) They are found in vertebrate hearts.
D) They conduct electrical impulses between cardiac cells.
E) all of these are true.

Question 20

The problem of electrical discontinuity caused in the normal heart by the connective tissue separating the atria from the ventricles is solved by

A) having the A-V node function as a secondary pacemaker.
B) having an ectopic pacemaker.
C) coordinating electrical activity in the atria with electrical activity in the ventricles by connecting them via the vagus nerve.
D) coordinating electrical activity in the atria with electrical activity in the ventricles by connecting them via the bundle of His.
E) coordinating electrical activity in the atria with electrical activity in the ventricles by connecting them via the Purkinje fibers.

Question 21

The movement of which two ions is responsible for maintaining the plateau phase of the action potential of contractile cardiac muscle cells?

A) Na⁺ and Cl^-
B) Na⁺ and K⁺
C) K⁺ and Cl^-
D) Ca²⁺ and Na⁺
E) Ca²⁺ and K⁺

Question 22

An increase in heart rate is accompanied by

A) an increase in L-type Ca²⁺ channel activity.
B) an increase in K⁺ flux through voltage-gated K⁺ channels.
C) an increase in the passive movement of Na⁺ into cells of the SA node.
D) an increase in the passive movement of K⁺ out of cells of the SA node.
E) a combined increase in passive movement of Na⁺ and K⁺ out of the cells of the SA node.

Question 23

In a normal ECG, no separate wave is detected for atrial repolarization because

A) the amount of atrial tissue is too little for the current to be detected by the ECG electrodes.
B) the time period between atrial depolarization and repolarization occurs too rapidly.
C) atrial repolarization and ventricular depolarization are simultaneous, and the expected wave is masked by the QRS complex.
D) None of these.

Question 24

At the onset of ventricular diastole, the A-V valves close as a result of

A) higher pressure in the atria relative to the ventricles.
B) higher pressure in the ventricles relative to the atria.
C) higher pressure in the arteries (pulmonary and aorta) relative to the ventricles.
D) higher pressure in the venae cavae relative to the atria.
E) contraction of the small muscles which attach to the valves.

Question 25

Ventricular systole includes the periods of

A) isometric contraction and ventricular ejection.
B) isovolumetric contraction and ventricular ejection.
C) isometric contraction and end-systolic volume.
D) isovolumetric contraction and end-systolic volume.
E) none of these

Question 26

Which of the following statements is NOT true regarding sympathetic stimulation of the heart?

A) It increases the rate of depolarization of the SA node.
B) It increases excitability of the AV node.
C) It results in stronger ventricular contractions.
D) It increases venous return.
E) None of these.

Question 27

Parasympathetic stimulation of the heart

A) increases venous return to the heart.
B) has an impact on the ventricular conduction pathway.
C) increases the number of cross-bridges that can form during contraction.
D) increases the strength of contraction.
E) none of these.

Question 28

Venous return and by extension end-diastolic volume are examples of factors directly related to the _____ control of stroke volume.

A) endocrine
B) nervous
C) extrinsic
D) intrinsic
E) sympathetic

Question 29

Which of the following will cause local adjustments in an arteriole's radius and hence vessel diameter?

A) decreased O₂
B) increased K⁺
C) increased O₂
D) increased acid
E) all of these.

Question 30

Venous return is affected by

A) the cardiac suction effect.
B) the respiratory pump.
C) the skeletal muscle pump.
D) none of these.
E) all of these.

Question 31

Which of the following decreases with increased muscular activity?

A) venous return
B) mean arterial blood pressure
C) peripheral resistance
D) blood flow to brain
E) none of these.

Question 32

The total cross-sectional area of arteries is less than that of the arterioles.

Question 33

Arteries but not veins have elastic fibers in their walls.

Question 34

Differences in flow are determined by the amount of vascularization and the amount of
resistance in the arterioles.

Question 35

Histamine whose release increases blood flow is released in response to local metabolic
changes that require greater delivery of oxygen.

Question 36

Nitric oxide (NO) interferes with platelet function and blood clotting.

Question 37

Concentration gradients not bulk flow of solutes determines the distribution of
extracellular fluids.

Question 38

While an individual is at rest about 20% of the total cardiac output goes to the kidneys.

Question 39

Both thrombocytes and platelets are living cells but they are found in different
organisms.

Question 40

Thrombin is formed in a positive-feedback cycle.

Question 41

It is exposed collagen that initiates the clotting cascade.

Question 42

Match each sentence with the most appropriate choice:

-Open circulatory system

A) Hemolymph
B) Hageman factor
C) Oxygen transport
D) Parasympathetic neurotransmitter
E) Clotting
F) Sympathetic neurotransmitter
G) "good cholesterol"
H) Elasmobranchs
I) Copper
J) Iron

Question 43

Match each sentence with the most appropriate choice:

-Factor XII

A) Hemolymph
B) Hageman factor
C) Oxygen transport
D) Parasympathetic neurotransmitter
E) Clotting
F) Sympathetic neurotransmitter
G) "good cholesterol"
H) Elasmobranchs
I) Copper
J) Iron

Question 44

Match each sentence with the most appropriate choice:

-Erythrocytes

A) Hemolymph
B) Hageman factor
C) Oxygen transport
D) Parasympathetic neurotransmitter
E) Clotting
F) Sympathetic neurotransmitter
G) "good cholesterol"
H) Elasmobranchs
I) Copper
J) Iron

Question 45

Match each sentence with the most appropriate choice:

-Acetylcholine

A) Hemolymph
B) Hageman factor
C) Oxygen transport
D) Parasympathetic neurotransmitter
E) Clotting
F) Sympathetic neurotransmitter
G) "good cholesterol"
H) Elasmobranchs
I) Copper
J) Iron

Question 46

Match each sentence with the most appropriate choice:

-Thrombocytes

A) Hemolymph
B) Hageman factor
C) Oxygen transport
D) Parasympathetic neurotransmitter
E) Clotting
F) Sympathetic neurotransmitter
G) "good cholesterol"
H) Elasmobranchs
I) Copper
J) Iron

Question 47

Match each sentence with the most appropriate choice:

-Norepinephrine

A) Hemolymph
B) Hageman factor
C) Oxygen transport
D) Parasympathetic neurotransmitter
E) Clotting
F) Sympathetic neurotransmitter
G) "good cholesterol"
H) Elasmobranchs
I) Copper
J) Iron

Question 48

Match each sentence with the most appropriate choice:

-High density lipoprotein

A) Hemolymph
B) Hageman factor
C) Oxygen transport
D) Parasympathetic neurotransmitter
E) Clotting
F) Sympathetic neurotransmitter
G) "good cholesterol"
H) Elasmobranchs
I) Copper
J) Iron

Question 49

Match each sentence with the most appropriate choice:

-Sinus venosus

A) Hemolymph
B) Hageman factor
C) Oxygen transport
D) Parasympathetic neurotransmitter
E) Clotting
F) Sympathetic neurotransmitter
G) "good cholesterol"
H) Elasmobranchs
I) Copper
J) Iron

Question 50

Match each sentence with the most appropriate choice:

-Hemacyanin

A) Hemolymph
B) Hageman factor
C) Oxygen transport
D) Parasympathetic neurotransmitter
E) Clotting
F) Sympathetic neurotransmitter
G) "good cholesterol"
H) Elasmobranchs
I) Copper
J) Iron

Question 51

Match each sentence with the most appropriate choice:

-Hemoglobin

A) Hemolymph
B) Hageman factor
C) Oxygen transport
D) Parasympathetic neurotransmitter
E) Clotting
F) Sympathetic neurotransmitter
G) "good cholesterol"
H) Elasmobranchs
I) Copper
J) Iron

Question 52

Compare and contrast the effect of sympathetic and parasympathetic stimulation on the SA node, AV node, arterial muscle, ventricular muscle, and veins.

Question 53

Describe the amphibian heart structure and the flow of blood through the heart and body.

Question 54

During periods stress and high anxiety, it may be important to have increased blood flow to skeletal muscle in particular. What are the overall effects of sympathetic stimulation on the heart and blood delivery.

Question 55

Although the Frank-Starling mechanism can be accounted for in terms of length-tension relationships, one could also invoke increases in cytosolic calcium resulting from opening of stretch-activated calcium channels. What role does calcium play in muscle contraction, and why would increasing cytosolic calcium levels increase the amount of tension developed?

Question 56

Capillaries are the vessels with the smallest diameter, yet they offer less resistance to flow than the arterioles. How can these facts be reconciled, given that resistance (R) is inversely proportional to the radius raised to the 4^th power (r⁴)?