Question 1

The_________ valve is between the right ventricle and the pulmonary artery.
A) tricuspid
B) semilunar
C) atrioventricular
D) bicuspid

Accepted Answer

The valve located between the right ventricle and the pulmonary artery is the pulmonary semilunar valve, which is a type of semilunar valve.

Question 2

The human heart contains cells that do all of the following EXCEPT
A) generate electrical signals.
B) contract.
C) create new red blood cells.
D) respond to signals from the nervous system.

Accepted Answer

The human heart contains cells that generate electrical signals (pacemaker cells), contract (cardiac muscle cells), and respond to signals from the nervous system. However, it does not contain cells that create new red blood cells; this function is primarily carried out by the bone marrow.

Question 3

Long-distance runners like to train at high altitudes because the lack of oxygen there stimulates the
A) body to produce more lung tissue.
B) muscles to contract faster.
C) capillaries to diffuse oxygen more slowly.
D) muscles to contract less strongly.
E) bone marrow to make more erythrocytes.

Accepted Answer

Training at high altitudes, where oxygen levels are lower, stimulates the body's bone marrow to produce more erythrocytes (red blood cells). This adaptation helps improve the oxygen-carrying capacity of the blood, which can enhance endurance performance when the athlete returns to lower altitudes.

Question 4

Erythropoietin
A) stimulates the spleen to release more red blood cells.
B) is produced by the pancreas.
C) is released only in response to hemorrhaging (bleeding).
D) is released in response to high carbon dioxide or low oxygen levels in the blood.

Accepted Answer

Erythropoietin is a hormone produced primarily by the kidneys in adults (and the liver in the fetus) that stimulates the production of red blood cells in the bone marrow. It is released in response to hypoxia, or low oxygen levels in the blood, not necessarily only due to hemorrhaging. This process helps to increase the oxygen-carrying capacity of the blood.

Question 5

Southern Copperhead snake venom contains a protein called disintegrin. Disintegrins bind to a class of membrane receptors called integrins. Platelets use integrin receptors to aggregate at a site of tissue damage. Why does the snake venom contain this molecule?
A) The molecule helps kill the snakeʹs prey by producing large clots that travel in the body and produce heart attacks and strokes.
B) By binding to the platelets, the molecule inhibits the formation of fibrin.
C) The molecule interferes with clot formation so that the venom can travel more efficiently from the site of the bite to the rest of the body.
D) After the snake bites its prey, the molecule helps in wound healing.

Accepted Answer

The molecule in snake venom interferes with clot formation, allowing the venom to spread more efficiently throughout the body of the prey.

Question 6

Plasma contains all of the following components EXCEPT
A) albumin.
B) water.
C) hormones.
D) lymph.

Accepted Answer

Lymph is not a component of plasma; it is a separate fluid that circulates in the lymphatic system, whereas plasma is the liquid component of blood.

Question 7

Females need more dietary iron than males because they
A) lose more iron (during menstruation).
B) have a smaller volume of blood.
C) have less bone marrow.
D) eat less red meat than males.
E) have fewer red blood cells.

Accepted Answer

Females generally need more dietary iron than males primarily because they lose blood during menstruation, which contains iron. This loss necessitates a higher intake to maintain healthy iron levels.

Question 8

Plasma is primarily
A) cells.
B) protein.
C) salt.
D) water.
E) gases.

Accepted Answer

Plasma is primarily composed of water, making up about 90-92% of its content.

Question 9

What is the cardiac cycle?
A) The passage of electrical impulses from the AV node to the SN node to heart muscle
B) The alternating relaxation and contraction of the heart chambers
C) The movement of blood from systemic to pulmonary circulation
D) The movement of blood from the heart to the lungs and then back to the heart

Accepted Answer

The cardiac cycle refers to the sequence of events that occur as the heart beats, involving the alternating relaxation (diastole) and contraction (systole) of the atria and ventricles to pump blood throughout the body.

Question 10

Some athletes use ʺblood doping,ʺ in which additional red blood cells are added to the blood prior to the competition. What is the effect of blood doping?
A) It increases oxygen delivery to muscles.
B) It changes the blood type.
C) It makes blood thinner so that it flows faster.
D) It decreases blood pressure.

Accepted Answer

Blood doping increases the number of red blood cells in the bloodstream, which enhances the blood's ability to carry oxygen to the muscles. This is beneficial for endurance by improving aerobic capacity and endurance performance.

Question 11

In a random screening of athletes at a recent event, a runner was disqualified for testing positive for an injected form of erythropoietin. Which of the following is a consequence of extra erythropoietin in the circulatory system?
A) More red blood cells
B) Low blood pressure
C) A low white blood cell count
D) ʺThinʺ blood that does not clot efficiently

Accepted Answer

Erythropoietin stimulates the bone marrow to produce more red blood cells, which can enhance oxygen delivery to tissues but also thicken the blood, potentially increasing the risk of clotting and hypertension, not thinning the blood or reducing its clotting efficiency.

Question 12

Ventricles force blood directly into the
A) capillaries.
B) arteries.
C) veins.
D) arterioles.
E) venules.

Accepted Answer

Ventricles are chambers in the heart that forcefully pump blood into the arteries. The right ventricle pumps blood into the pulmonary arteries (to the lungs), and the left ventricle pumps blood into the aorta (to the rest of the body).

Question 13

All of the following are true of the SA node EXCEPT that it
A) directly stimulates the atria.
B) directly stimulates the ventricles.
C) is the pacemaker.
D) is influenced by nerve impulses and hormones.

Accepted Answer

The SA node (sinoatrial node) is responsible for setting the pace of the heart and initiates the heartbeat by causing the atria to contract. However, it does not directly stimulate the ventricles. The impulse from the SA node is transmitted to the ventricles through the AV node (atrioventricular node) and the bundle of His.

Question 14

When your blood pressure is measured from an artery in your arm, it is a measurement of the pressure produced by your
A) left ventricle.
B) right ventricle.
C) right atrium.
D) left atrium.

Accepted Answer

The left ventricle is responsible for pumping oxygenated blood into the aorta and throughout the body, creating the pressure measured when taking blood pressure from an artery in the arm.

Question 15

The average red blood cell lives for about_________ days.
A) 100
B) 120
C) 150
D) 90

Accepted Answer

The average lifespan of a red blood cell is about 120 days.

Question 16

The most abundant cell type in blood is the
A) leukocyte.
B) platelet.
C) erythrocyte.
D) neutrophil.
E) basophil.

Accepted Answer

Erythrocytes, or red blood cells, are the most abundant cell type in the blood, responsible for transporting oxygen throughout the body.

Question 17

Each of the following types of white blood cells is found within the circulatory system EXCEPT
A) macrophages.
B) monocytes.
C) leukocytes.
D) lymphocytes.

Accepted Answer

Macrophages are not typically found circulating in the blood; they reside in tissues throughout the body where they play a role in the immune response by phagocytizing pathogens and dead cells. Monocytes, leukocytes (a broad category that includes all white blood cells), and lymphocytes are all components of the circulatory system.

Question 18

Which blood constituent makes up most of the volume of blood?
A) White blood cells
B) Red blood cells
C) Plasma
D) Blood proteins

Accepted Answer

Plasma makes up about 55% of the total blood volume, making it the largest component. Red and white blood cells, along with platelets, are suspended in plasma, which is primarily water, electrolytes, and proteins.

Question 19

How many molecules of oxygen can bind with one molecule of human hemoglobin?
A) One
B) Two
C) Three
D) Four
E) Five

Accepted Answer

One molecule of human hemoglobin can bind with four molecules of oxygen. This is because hemoglobin is made up of four subunits, each of which can bind one oxygen molecule.

Question 20

Erythrocytes are produced in the
A) spleen.
B) heart.
C) liver.
D) bone marrow.

Accepted Answer

Erythrocytes, or red blood cells, are primarily produced in the bone marrow, a process known as erythropoiesis.

Quiz 33: Circulation

The_________ valve is between the right ventricle and the pulmonary artery.

The human heart contains cells that do all of the following EXCEPT

Long-distance runners like to train at high altitudes because the lack of oxygen there stimulates the

Erythropoietin

Southern Copperhead snake venom contains a protein called disintegrin. Disintegrins bind to a class of membrane receptors called integrins. Platelets use integrin receptors to aggregate at a site of tissue damage. Why does the snake venom contain this molecule?

Plasma contains all of the following components EXCEPT

Females need more dietary iron than males because they

Plasma is primarily

What is the cardiac cycle?

Some athletes use ʺblood doping,ʺ in which additional red blood cells are added to the blood prior to the competition. What is the effect of blood doping?

In a random screening of athletes at a recent event, a runner was disqualified for testing positive for an injected form of erythropoietin. Which of the following is a consequence of extra erythropoietin in the circulatory system?

Ventricles force blood directly into the

All of the following are true of the SA node EXCEPT that it

When your blood pressure is measured from an artery in your arm, it is a measurement of the pressure produced by your

The average red blood cell lives for about_________ days.

The most abundant cell type in blood is the

Each of the following types of white blood cells is found within the circulatory system EXCEPT

Which blood constituent makes up most of the volume of blood?

How many molecules of oxygen can bind with one molecule of human hemoglobin?

Erythrocytes are produced in the