Deck 23: The Circulatory System

Question 1

Which of the following has the smallest diameter?

A) venule
B) capillary
C) artery
D) arteriole

Answer 1

B

Question 2

For a blood pressure reading of 110/60, the number 60 represents the pressure in the

A) arteries while the left ventricle is refilling.
B) arteries while the left ventricle is contracting.
C) capillaries while the right ventricle is contracting.
D) arteries leading from the right ventricle to the lungs.

Answer 2

A

Question 3

Blood reaching the lungs in the pulmonary circuit

A) is rich in oxygen and carries little carbon dioxide.
B) is poor in oxygen and carries carbon dioxide from body cells.
C) returns to the heart through the systemic circuit.
D) returns to the heart through the right atrium.

Answer 3

B

Question 4

The pulse that can be felt in an artery is actually the

A) pressure due to muscular contractions of the veins.
B) pressure due to materials leaving the capillaries.
C) backflow of blood in the veins.
D) bulging of artery walls due to pressure generated by a contraction of the heart.

Question 5

The wall of the right ventricle of the heart is thinner than that of the left side of the heart because the right ventricle of the heart

A) pumps blood to the body, which requires low pressure to prevent damage to fragile body capillaries.
B) pumps blood to the lungs, which are not very far from the heart and, therefore, require less pressure to reach.
C) pumps blood to the left ventricle, a very short distance that requires little pressure.
D) has a smaller chamber than the left side. The thinner wall provides more space for blood.

Question 6

Which of the following describes the flow of blood in humans?

A) heart to veins to capillaries to arteries back to heart
B) heart to capillaries to veins to arteries back to heart
C) heart to arteries to capillaries to veins back to heart
D) heart to capillaries to arteries to veins back to heart

Question 7

Which of the following describes the flow of blood in humans?

A) from lungs to left atrium to left ventricle to body to right atrium to right ventricle to lungs
B) from lungs to left ventricle to left atrium to body to right atrium to right ventricle to lungs
C) from lungs to right atrium to left ventricle to body to left atrium to right ventricle to lungs
D) from lungs to left atrium to right ventricle to body to right atrium to left ventricle to lungs

Question 8

In mammalian hearts, atria are separated from ventricles by

A) one-way valves.
B) two-way valves.
C) porous valves.
D) capillary valves.

Question 9

In mammalian hearts,

A) all four chambers contract at the same time.
B) the left and right ventricles contract alternately.
C) the left atrium and ventricle contract simultaneously.
D) the left and right ventricles contract at the same time.

Question 10

The human circulatory system

A) uses gravity to move blood to tissues.
B) connects only to the most vital organs in the body.
C) depends on veins to pump the blood through our bodies.
D) is considered a closed system.

Question 11

Which of the following statements about human blood pressure is true?

A) Blood pressure is higher in the arteries from the right ventricle than in those from the left ventricle.
B) As blood enters the capillaries, blood pressure is higher than the pressure in the arteries leaving the left ventricle.
C) As blood enters the capillaries, blood pressure is higher than the pressure of blood leaving the capillaries.
D) Blood pressure in the arteries is lower than the pressure of blood leaving the capillaries.

Question 12

When you begin exercising, which of the following does not change?

A) heart rate
B) blood volume
C) blood pressure
D) distribution of blood.

Question 13

In the artery leaving the left ventricle, you would expect to find

A) oxygenated blood.
B) deoxygenated blood.
C) a smaller volume of blood than in any of the other vessels leaving the heart.
D) lower systolic pressure than in any of the other vessels leaving the heart.

Question 14

The left side of the heart pumps blood

A) directly to the right side of the heart.
B) into the systemic system.
C) into veins.
D) to the lungs.

Question 15

Which of the following changes does not occur when a person engages in heavy exercise?

A) The supply of blood to the active muscles decreases.
B) The number of times the heart beats each minute increases dramatically.
C) The blood vessels stretch, which allows them to carry more blood.
D) The blood pressure in the arteries increases.

Question 16

Which of the following is not one of the three kinds of human blood vessels?

A) capillary
B) vein
C) alveolus
D) artery

Question 17

Which of the following statements about the internal transport of materials in large animals is true?

A) Since diffusion works well only over short distances, nearly all animal body cells lie extremely close to a blood vessel.
B) Diffusion is the main mechanism large animals use to transport materials within their systems.
C) The exchange of materials between blood and the surrounding cells occurs in arteries.
D) The heart contains the surfaces over which most gas exchange occurs.

Question 18

Which of the following is true of blood?

A) The liquid portion of blood contains ions, nutrients, and hormones.
B) All of the cells found in blood are involved in fighting off infections.
C) Red blood cells have two nuclei.
D) Only the cellular portion of the blood is important in carrying gases like oxygen and carbon dioxide

Question 19

In the human heart, atria pump blood into

A) arteries.
B) veins.
C) ventricles.
D) lungs.

Question 20

Which of the following blood pressures would indicate a healthy heart?

A) 102/23 mm Hg
B) 40/120 mm Hg
C) 113/69 mm Hg
D) 248/130 mm Hg

Question 21

The pressure needed to move blood from the body back to the heart is created by the contraction of the

A) skeletal muscles of the body.
B) left ventricle of the heart.
C) one-way valves in the veins.
D) walls of the veins.

Question 22

The figure below shows how a pacemaker aids in the regulation of a human heart.
As a result of step 3 in this figure,

A) the atria are in systole.
B) the right side of the heart is in diastole.
C) both the atria and the ventricles are in systole.
D) the ventricles are in systole.

Question 23

Arteries and veins, which transport materials over large distances within humans, are relatively large in diameter so that

A) their surface area-to-volume ratio is large.
B) their walls are less muscular.
C) the friction drag of the blood is reduced.
D) they are well suited to gas exchange.

Question 24

Which of the following is not a reason that capillaries are highly branched?

A) Branching creates very narrow vessels that only allow one blood cell through at a time. Forcing blood cells into single-file lines ensures that they do not form clots.
B) The many branches of capillaries allow the circulatory system to spread out so that no cell in the body is out of range of rapid diffusion from the blood.
C) Branching slows down the flow of blood by increasing frictional drag. Slower blood flow allows more time for the exchange of gases and nutrients.
D) Branching increases the surface area of the capillaries creating more surface area over which gas and nutrient exchange can occur.

Question 25

This figure depicts blood pressure in different regions of the body as a result of the contraction and relaxation of the left ventricle.
The arrow indicates the amount of pressure in the ______________ of the left ventricle.

A) lungs during systole
B) systemic arteries near the heart during diastole
C) lungs during diastole
D) systemic arteries near the heart during systole

Question 26

Which of the following would have an open circulatory system?

A) a mouse
B) a honeybee
C) an alligator
D) a human

Question 27

Which of the following statements about open circulatory systems is false?

A) Animals with open circulatory systems have little control over how the blood circulates.
B) Blood contents are distributed less efficiently than in closed circulatory systems.
C) Blood makes its way back to the heart through a system of veins.
D) The vessels leading from the heart direct blood into the spaces between the organs.

Question 28

All animals with closed circulatory systems have a heart with at least

A) two ventricles.
B) two atria and one ventricle.
C) one atrium and one ventricle.
D) two atria and two ventricles.

Question 29

Excess cholesterol can cause sticky deposits to form on the walls of blood vessels. Why does the presence of these deposits raise the likelihood of a heart attack?

A) The cholesterol turns into steroid hormones, and the excess hormones stress the heart muscle.
B) The cholesterol makes the blood thicker, causing the heart to have to work harder to push it through the vessels.
C) The deposits decrease the vessel diameter, thus increasing friction drag and stressing the heart as it pumps the blood.
D) The cholesterol cuts off the blood supply to the capillaries, stressing the heart as it tries to force blood into them.

Question 30

Which of the following is not a complication of cardiovascular disease?

A) The interior of the person's capillaries increases in diameter.
B) The person's heart must work harder to force blood through the narrowed arteries.
C) The reduction of oxygen and nutrients to heart muscle can cause a heart attack.
D) The heart's ability to pump blood may be reduced.

Question 31

Capillaries are specialized for

A) bulk flow of blood.
B) acting as one-way valves.
C) supplemental pumping of blood.
D) exchange of materials with body cells.

Question 32

The slow flow of blood through capillaries

A) allows time for the exchange of gases and other materials.
B) prevents the loss of red blood cells to the interstitial fluid.
C) allows arterioles and venules to retain sufficient oxygen.
D) prevents surrounding cells from becoming detached from one another.

Question 33

After a physical, your doctor tells you that your high-density lipoproteins are high and your low-density lipoproteins are low. Should you be concerned?

A) No; these results indicate that cholesterol is being removed through your digestive tract rather than being stored in your liver.
B) No; these results indicate that excess cholesterol is being efficiently removed from your blood.
C) Yes; these results indicate that there is excess cholesterol in your blood, which might be deposited on the lining of your blood vessels.
D) Yes; these results indicate that you are not consuming enough cholesterol to maintain the plasma membranes of your cells or produce important hormones.

Question 34

A friend complains to you about the painful varicose veins in her legs. After recommending that she see her doctor, what could you suggest to relieve her discomfort?

A) She should stand up but not move around much so that the muscles in the walls of her veins can focus on pumping her blood upward.
B) She should stop drinking fluids so that her body has time to absorb the excess fluids that have built up in her legs.
C) She should walk around so that the muscle in her legs can push against the walls of her veins and push her blood upward.
D) Should remove any item of clothing that creates pressure against her legs (socks or stockings) so that the blood is free to move.

Question 35

A mechanical pacemaker is implanted into a patient with irregular heart beats. If the pacemaker has just one electrode that can stimulate just one spot on the heart, where should that electrode be placed?

A) in the wall between the left ventricle and the right ventricle
B) in the wall between the left atrium and the right atrium
C) on the sinoatrial node
D) on the atrioventricular node

Question 36

Occasionally, babies are born with a tiny hole between their left and right atria. Usually, the hole closes during early childhood, but if not, the child must undergo surgery to close the hole. Why is this hole likely to be a problem?

A) The hole would weaken the muscles in the atria, making it difficult for them to pump blood to the body.
B) The hole would allow blood in the left ventricle to be pushed backward into the right atrium rather than being pumped to the body.
C) The hole would allow the mixing of oxygenated and nonoxygenated blood, decreasing the efficiency of the cardiovascular system.
D) The hole would prevent any blood from reaching the lungs.

Question 37

Which of the following is not an adaptation capillaries have evolved that makes them more efficient at exchanging materials between blood and the adjacent tissues?

A) a small surface area-to-volume ratio
B) very thin walls
C) small diameter
D) porous walls

Question 38

The open circulatory systems of insects

A) lack one-way valves.
B) carry oxygen more efficiently than closed circulatory systems.
C) use a blood-like liquid to distribute nutrients.
D) play a role in gas exchange.

Question 39

Animals with open circulatory systems

A) have only a pulmonary circuit.
B) have only a systemic circuit.
C) have circulation but no complete blood circuits.
D) have arterioles but not venules.

Question 40

When a person sits for long periods of time without moving, fluid may accumulate in the feet and ankles. What aspect of a person's body would generally assist the circulatory system in returning this fluid (which is blood plasma) back into the circulation?

A) the movement of skeletal muscle
B) the muscular contractions of digestion
C) the pull of gravity
D) the friction drag within the blood vessels

Question 41

Capillaries are generally larger in diameter than veins.

Question 42

The saliva of leeches contains chemicals that ______ the rate of blood flow and _______ the clotting of blood.

Question 43

The drop in blood pressure as the blood progresses through the circulatory system is due to the effect of _______ between flowing blood and the blood vessel walls.

Question 44

How does taking a drug like erythropoietin (EPO) benefit an athlete?

A) Since EPO thickens the blood, it forces the heart to work harder. At the time of competition, the heart is then stronger and more efficient at delivering oxygen to the athlete's muscle cells.
B) Since EPO increases the ability of mitochondria to make ATP in the absence of oxygen, muscle cells can produce energy even when the athlete is out of breath.
C) Since EPO binds to cholesterol and removes it from the body, it cleans the blood vessels. Clear blood vessels mean better blood flow and delivery of oxygen.
D) Since EPO increases the number of red blood cells, it increases the amount of oxygen the athlete's blood can carry, and this gives the athlete greater endurance.

Question 45

The three-chambered heart of a frog is ________ [more or less?] efficient than the four-chambered heart of a vertebrate.

Question 46

Capillary walls are made exclusively of _______ cells.

Question 47

A _________ _________ occurs when the supply of blood to the heart muscle is cut off because the arteries leading to the heart are blocked.

Question 48

Each heartbeat we experience lasts a little less than 1 second and consists of a series of events called the _______ cycle.

Question 49

The process of _______ is too slow to transport essential materials from one part of a multicellular organism to another.

Question 50

Muscular animal hearts must generate enough force to lift blood against the pull of _______.

Question 51

In an insect's _______ circulatory system, blood flows through the body cavity around the organs.

Question 52

The sound of a human heartbeat as heard through a stethoscope is caused by the closing of valves within the heart.

Question 53

The pressure in the arteries is highest while the heart is contracting.

Question 54

When the muscles of the heart relax, the blood flows backward, forcing the ___________ between the chambers to close.

Question 55

Ultimately, the rhythm of the heart is controlled by the nervous system and a variety of signaling compounds like hormones.

Question 56

An increase in the amount of water in the body can increase the overall volume of the blood causing a health condition known as ___________.

Question 57

_______ are the vessels that carry blood from the heart for distribution to the body.

Question 58

In human hearts, ventricles receive blood directly from _____.

Question 59

The sinoatrial (SA) node is also called the pacemaker of the heart because it determines the _________ at which the heart beats.

Question 60

"Good" cholesterol is carried in _____-density lipoproteins.

Question 61

Large animals like giraffes require less pressure than smaller animals do to move blood throughout their bodies.

Question 62

The muscle cells of the heart get their oxygen and nutrients from blood flowing through the heart's four chambers.

Question 63

Aneurysms cause high blood pressure.

Question 64

Hypertension causes low blood pressure in the kidneys, which makes it more difficult for the kidneys to perform their function of filtering the blood.

Question 65

In our hearts, the left and right atria contract at the same time.

Question 66

The structure depicted in the figure below (enlarged to give you a better view) uses muscles to open and close in response to the pull of gravity.

Question 67

Why are arteries surrounded by thick walls of muscle?

Question 68

Oxygen is transported to the cells of an insect through its open circulatory system.