CHAPTER 27 Test Your Knowledge
DRIVING QUESTION 1
What structures make up the cardiovascular system, and how does blood flow through the system?
By answering the questions below and studying Infographics 27.2 and 27.3, you should be able to generate an answer for the broader Driving Question above.
KNOW IT
List the three components of the cardiovascular system.
the blood, blood vessels, and the heart
Blood enters the systemic circuit from
a. the lungs.
b. the left side of the heart.
c. the right side of the heart.
d. the body.
e. both b and c
b
Which of the following is the correct order of structures that blood flows through as it passes through the cardiovascular system?
a. right side of heart→body→left side of heart→lungs
b. left side of heart→body→right side of heart→lungs
c. left side of heart→right side of heart→body→lungs
d. right side of heart→left side of heart→lungs→body
b
USE IT
In which circuit (pulmonary or systemic) does blood pick up nutrients, such as sugar?
systemic
Are the coronary arteries part of the pulmonary or the systemic circuit? Explain your answer.
Coronary arteries are part of the systemic circuit: they deliver blood to an important organ in the body, the heart.
During heart surgery, patients are often placed on a heart–lung machine (known as a cardiopulmonary bypass). This machine circulates and oxygenates blood during the operation, taking over for the patient's heart and lungs. At what points would the patient's blood have to be diverted into the machine and back into the body in order to properly bypass the flow of blood through the heart and lungs?
The patient’s blood would have to be diverted just before it returns from the body to the right atrium of the heart. The machine would then oxygenate the blood and return it to the aorta, from which it would be carried to the body.
DRIVING QUESTION 2
What is the structure of the heart and of the different types of blood vessel?
By answering the questions below and studying Infographics 27.2 and 27.3, you should be able to generate an answer for the broader Driving Question above.
KNOW IT
Blood returning to the heart from the lungs enters the _________.
a. right atrium
b. right ventricle
c. left atrium
d. left ventricle
e. coronary arteries
c
Which chamber of the heart pumps oxygen-rich blood to the body?
a. the right atrium
b. the right ventricle
c. the left atrium
d. the left ventricle
e. both the right atrium and the left atrium (to the right and left sides of the body, respectively)
d
How does the heart obtain oxygen?
a. from the blood in its chambers
b. from the coronary arteries
c. from the systemic arteries
d. from the coronary veins
e. from the systemic veins
b
What is the defining feature of an artery?
a. It carries blood away from the heart.
b. It has very thin walls.
c. It has valves.
d. It carries oxygenated blood.
e. both a and d
a
USE IT
Atrial fibrillation is a condition in which the atria contract very rapidly and irregularly. The ventricles also contract faster than normally, but their contraction is not coordinated with the atrial contraction. Explain how this can disrupt blood supply to the body.
If the contraction of the atria and of the ventricles are not coordinated, blood cannot be moved smoothly through the heart. If the atria are contracting very rapidly, they may not deliver the normal amount of blood to the ventricles. If the left ventricle is not completely filled when it contracts, less blood than normal will be delivered to the body.
Which of the following is most likely to be associated with left-side heart failure?
a. fluid backing up in the feet and legs, causing swelling
b. increased systolic pressure in the aorta
c. reduced oxygenation of the blood leaving the left ventricle
d. fluid backing up in the lungs, causing shortness of breath
e. increased oxygenation of the blood returning to the right atrium
d
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Some babies are born with a congenital heart defect in which the septum, or wall, between the left and right ventricles has an opening in it, and the aorta therefore can accept blood from both the left and right ventricles. These babies are known as “blue babies.” Why?
If oxygenated blood in the left ventricle mixes with less-oxygenated blood in the right ventricle, the total oxygenation of blood in the left ventricle is reduced. When this blood is pumped to the body, it appears more like the deoxygenated in veins, imparting a blue color to these babies.
DRIVING QUESTION 3
What is the composition of blood, and what does blood do?
By answering the questions below and studying Infographics 27.5 and 27.6, you should be able to generate an answer for the broader Driving Question above.
KNOW IT
Describe the function of each of the following cellular components of blood: white blood cells; red blood cells; platelets.
Different white blood cells have different specific functions, but overall, white blood cells are important for the immune response. Red blood cells carry oxygen and deliver it to cells. Platelets are important in blood clotting.
Which of the following is not true of capillaries?
a. Blood moves through them slowly.
b. They have a very small diameter.
c. They have very thin walls.
d. They occur between arteries and veins.
e. They have valves.
e
What is happening in a capillary in your big toe?
a. Oxygen is diffusing from the blood into your toe tissue.
b. Carbon dioxide is diffusing from your toe tissue into the blood.
c. Nutrients are diffusing from the blood into your toe tissue.
d. all of the above
e. a and c
d
USE IT
TV crime dramas often analyze arterial spray patterns of blood at crime scenes. Why do you never hear about venous spray patterns?
The blood in arteries is under high pressure, so when an artery is severed or damaged, blood will spray out under pressure. Once blood enters the veins (from capillaries) it is no longer under high pressure, so will not spray if a vein is severed.
Why are soldiers standing at attention for long periods of time advised to contract their calf muscles to avoid becoming light-headed?
The veins in legs, which return blood to the heart, run through skeletal muscle. When soldiers contract their calf muscles, that contraction applies a squeeze to the blood in the veins, pushing it up and to the next valve. This helps blood continue to move up against the force of gravity. If the blood is not given an extra push, it may start to pool in the lower extremities, leaving insufficient blood for the rest of the body and causing light-headedness.
DRIVING QUESTION 4
What is cardiovascular disease, and what are some of the risk factors for developing cardiovascular disease?
By answering the questions below and studying Infographics 27.4, 27.7, 27.8, and 27.9, you should be able to generate an answer for the broader Driving Question above.
KNOW IT
Match the disease (left column) with the letter corresponding to its underlying cause (right column).
heart attack—C; hypertension—A; stroke—D; atherosclerosis—B
List at least four risk factors for cardiovascular disease. For each, state whether or not it is modifiable.
There are many possibilities. Some include family history/genetics (not modifiable); diet (modifiable); exercise (modifiable); race (not modifiable); smoking (modifiable); obesity (modifiable to a certain extent). Type 2 diabetes and hypertension are risk factors that have both modifiable and unmodifiable aspects; in both cases, proper management after diagnosis is important and modifiable.
Why does atherosclerosis increase the risk of stroke?
The plaques of atherosclerosis can rupture, promoting blood clot formation. If these clots travel to and block a blood vessel in the brain, a stroke can occur.
Which type of cholesterol is dangerous with respect to cardiovascular disease?
a. HDL
b. LDL
c. both
d. neither—cholesterol is a healthy lipid
e. HDL is a risk for hypertension and LDL is a risk for atherosclerosis.
b
USE IT
The data generated from the Bogalusa study show a correlation between atherosclerosis and risk factors for cardiovascular disease. Does this mean that everyone with a risk factor (e.g., high BMI) will develop atherosclerosis? Explain your answer.
No; correlation does not mean causation. However, given the correlation, it is wise to reduce one’s risk factors to the extent possible.
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MINI CASE
Steven is 14 years old. He is an ace goalie for his soccer team, which practices twice during the week and plays a game every weekend. He is also an ace online gamer, holding the highest player skill level in World of Warcraft. After many long afternoons of playing, Steven is also a great graphic designer and his mother pays him to design computer-generated fliers for her business. She prepares healthy meals with lots of whole grains, fruits, and dairy (milk and cheese), and she gets regular checkups to monitor her elevated blood pressure. Steven spends some of his money on chocolate bars and potato chips. He is a big guy, and in the heaviest 5% of his age group. From what you've read in this chapter, what cardiovascular risk factors do you identify in Steven? What could you say to Steven and his mom about Steven's potential risk and reducing that risk?
Steven is clearly a talented young person. However, he appears to practice or play soccer only three times a week, and as goalie he may not run as much as some of the other players on the team. He spends a lot of time sitting in front of his video game and computer, which may be taking time away from exercise. He seems to eat a healthy diet, although if he is eating full-fat milk and cheese, that may be more fat and cholesterol than is ideal. His size also puts him at risk for future cardiovascular disease. His mother has high blood pressure, so that is a family risk factor for him. Steven may benefit from getting more moderate to strenuous exercise, from switching to lower-fat diary products, and perhaps from cutting back on some of his less healthful chips and chocolate bars. These modifications should help him get his weight into a healthy range, which will help reduce his risk factors.
INTERPRETING DATA
Refer to Infographic 27.10 and record your answers to the following questions in the table below.
a. Look at the 2010 data for Texas, Arizona, California, South Dakota and your home state. For each state, record the average percentage of adults with BMI =30.
b. Now determine the total population of each state (you can find census data at quickfacts.census.gov/qfd/index.htm).
c. Now determine the total number of people in each of those states who experienced these cardiovascular events.
| State | Adults with BMI ≥ 30 (%) | Adults with BMI ≥30 (%) | Number of Adults with BMI ≥ 30 |
| Texas | 30% | 26,059,203 | 7,817,761 |
| Arizona | 22% | 6,553,255 | 1,441,716 |
| California | 22% | 38,041,430 | 8,369,115 |
| South Dakota | 27.5% | 833,354 | 229,172 |
| Your home state | Answers will vary. | Answers will vary. | Answers will vary. |
BRING IT HOME
Evaluate your own health and lifestyle with respect to risk for cardiovascular disease. Consider what kinds of changes you might want to talk to your physician about.
There are many possible answers. Consider the risk factors discussed in the chapter, and which of these may require medical intervention.