INSTRUCTOR ANSWER GUIDE
OPENSTAX ANATOMY & PHYSIOLOGY
2ND EDITION
UNIT 1: LEVELS OF ORGANIZATION
CHAPTER 1: AN INTRODUCTION TO THE HUMAN BODY
Interactive Link Questions
1. View this animation (http://openstaxcollege.org/l/metabolic) to learn more about metabolic
processes. What kind of catabolism occurs in the heart?
Answer: Fatty acid catabolism.
2. Water concentration in the body is critical for proper functioning. A person’s body retains
very tight control on water levels without conscious control by the person. Watch this video
(http://openstaxcollege.org/l/H2Ocon) to learn more about water concentration in the body.
Which organ has primary control over the amount of water in the body?
Answer: The kidneys.
3. A CT or CAT scan relies on a circling scanner that revolves around the patient’s body. Watch
this video (http://openstaxcollege.org/l/CATscan) to learn more about CT and CAT scans. What
type of radiation does a CT scanner use?
Answer: X-rays.
4. A patient undergoing an MRI is surrounded by a tube-shaped scanner. Watch this video
(http://openstaxcollege.org/l/MRI) to learn more about MRIs. What is the function of magnets in
an MRI?
Answer: The magnets induce tissue to emit radio signals that can show differences between
different types of tissue.
5. PET relies on radioactive substances administered several minutes before the scan. Watch this
video (http://openstaxcollege.org/l/PET) to learn more about PET. How is PET used in
chemotherapy?
Answer: PET scans can indicate how patients are responding to chemotherapy
REVIEW QUESTIONS
6. Which of the following specialties might focus on studying all of the structures of the ankle
and foot?
Answer: C. regional anatomy
7. A scientist wants to study how the body uses foods and fluids during a marathon run. This
scientist is most likely a(n) ________.
Answer: A. exercise physiologist
, Page |2
8. The smallest independently functioning biological unit of an organism is a(n) ________.
Answer: A. cell
9. A collection of similar tissues that performs a specific function is an ________.
Answer: A. organ
10. The body system responsible for structural support and movement is the ________.
Answer: D. skeletal system
11. Metabolism can be defined as the ________.
Answer: D. sum of all chemical reactions in an organism
12. Adenosine triphosphate (ATP) is an important molecule because it ________.
Answer: C. stores energy for use by body cells
13. Cancer cells can be characterized as “generic” cells that perform no specialized body
function. Thus cancer cells lack ________.
Answer: A. differentiation
14. Humans have the most urgent need for a continuous supply of ________.
Answer: C. oxygen
15. Which of the following statements about nutrients is true?
Answer: A. All classes of nutrients are essential to human survival.
16. C.J. is stuck in a car during a bitterly cold blizzard. CJ’s body responds to the cold by
________.
Answer: C. breaking down stored energy
17. After you eat lunch, nerve cells in your stomach respond to the distension (the stimulus)
resulting from the food. They relay this information to ________.
Answer: A. a control center
18. Stimulation of the heat-loss center causes ________.
Answer: C. sweat glands to increase their output
19. Which of the following is an example of a normal physiologic process that uses a positive
feedback loop?
Answer: B. childbirth
20. What is the position of the body when it is in the “normal anatomical position?”
Answer: D. None of the above
21. To make a banana split, you halve a banana into two long, thin, right and left sides along the
________.
Answer: C. midsagittal plane
22. The lumbar region is ________.
, Page |3
Answer: D. superior to the popliteal region
23. The heart is within the ________.
Answer: B. mediastinum
24. In 1901, Wilhelm Röntgen was the first person to win the Nobel Prize for physics. For what
discovery did he win?
Answer: D. X-rays
25. Which of the following imaging techniques would be best to use to study the uptake of
nutrients by rapidly multiplying cancer cells?
Answer: C. PET
26. Which of the following imaging studies can be used most safely during pregnancy?
Answer: C. ultrasound
27. What are two major disadvantages of MRI scans?
Answer: B. high cost and the need for shielding from the magnetic signals
CRITICAL THINKING QUESTIONS
28. Name at least three reasons to study anatomy and physiology.
Answer: An understanding of anatomy and physiology is essential for any career in the health
professions. It can also help you make choices that promote your health, respond appropriately to
signs of illness, make sense of health-related news, and help you in your roles as a parent,
spouse, partner, friend, colleague, and caregiver.
29. For whom would an appreciation of the structural characteristics of the human heart come
more easily: an alien who lands on Earth, abducts a human, and dissects his heart, or an anatomy
and physiology student performing a dissection of the heart on her very first day of class? Why?
Answer: A student would more readily appreciate the structures revealed in the dissection. Even
though the student has not yet studied the workings of the heart and blood vessels in her class,
she has experienced her heart beating every moment of her life, has probably felt her pulse, and
likely has at least a basic understanding of the role of the heart in pumping blood throughout her
body. This understanding of the heart’s function (physiology) would support her study of the
heart’s form (anatomy).
30. Name the six levels of organization of the human body
Answer: Chemical, cellular, tissue, organ, organ system, organism.
31. The ovaries and the testes are a part of which body system? Can these organs be members of
more than one organ system? Why or why not?
Answer: The ovaries and the testes are parts of the reproductive system. But they also secrete
hormones, as does the endocrine system, therefore ovaries and testes function within both the
endocrine and reproductive systems.
, Page |4
32. Explain why the smell of smoke when you are sitting at a campfire does not trigger alarm,
but the smell of smoke in your residence hall does.
Answer: When you are sitting at a campfire, your sense of smell adapts to the smell of smoke.
Only if that smell were to suddenly and dramatically intensify would you be likely to notice and
respond. In contrast, the smell of even a trace of smoke would be new and highly unusual in your
residence hall, and would be perceived as danger.
33. Identify three different ways that growth can occur in the human body.
Answer: Growth can occur by increasing the number of existing cells, increasing the size of
existing cells, or increasing the amount of non-cellular material around cells.
34. When you open a bottle of sparkling water, the carbon dioxide gas in the bottle form bubbles.
If the bottle is left open, the water will eventually “go flat.” Explain these phenomena in terms of
atmospheric pressure.
Answer: In a sealed bottle of sparkling water, carbon dioxide gas is kept dissolved in the water
under a very high pressure. When you open the bottle, the pressure of the gas above the liquid
changes from artificially high to normal atmospheric pressure. The dissolved carbon dioxide gas
expands, and rises in bubbles to the surface. When a bottle of sparkling water is left open, it
eventually goes flat because its gases continue to move out of solution until the pressure in the
water is approximately equal to atmospheric pressure.
35. On his midsummer trek through the desert, Josh ran out of water. Why is this particularly
dangerous?
Answer: The primary way that the body responds to high environmental heat is by sweating;
however, sweating requires water, which comes from body fluids, including blood plasma. If
Josh becomes dehydrated, he will be unable to sweat adequately to cool his body, and he will be
at risk for heat stroke as his blood pressure drops too much from the loss of water from the blood
plasma.
36. Identify the four components of a negative feedback loop and explain what would happen if
secretion of a body chemical controlled by a negative feedback system became too great.
Answer: The four components of a negative feedback loop are: stimulus, sensor, control center,
and effector. If too great a quantity of the chemical were excreted, sensors would activate a
control center, which would in turn activate an effector. In this case, the effector (the secreting
cells) would be adjusted downward.
37. What regulatory processes would your body use if you were trapped by a blizzard in an
unheated, uninsulated cabin in the woods?
Answer: Any prolonged exposure to extreme cold would activate the brain’s heat-gain center.
This would reduce blood flow to your skin, and shunt blood returning from your limbs away
from the digits and into a network of deep veins. Your brain’s heat-gain center would also
increase your muscle contraction, causing you to shiver. This increases the energy consumption
of skeletal muscle and generates more heat. Your body would also produce thyroid hormone and
epinephrine, chemicals that promote increased metabolism and heat production.
OPENSTAX ANATOMY & PHYSIOLOGY
2ND EDITION
UNIT 1: LEVELS OF ORGANIZATION
CHAPTER 1: AN INTRODUCTION TO THE HUMAN BODY
Interactive Link Questions
1. View this animation (http://openstaxcollege.org/l/metabolic) to learn more about metabolic
processes. What kind of catabolism occurs in the heart?
Answer: Fatty acid catabolism.
2. Water concentration in the body is critical for proper functioning. A person’s body retains
very tight control on water levels without conscious control by the person. Watch this video
(http://openstaxcollege.org/l/H2Ocon) to learn more about water concentration in the body.
Which organ has primary control over the amount of water in the body?
Answer: The kidneys.
3. A CT or CAT scan relies on a circling scanner that revolves around the patient’s body. Watch
this video (http://openstaxcollege.org/l/CATscan) to learn more about CT and CAT scans. What
type of radiation does a CT scanner use?
Answer: X-rays.
4. A patient undergoing an MRI is surrounded by a tube-shaped scanner. Watch this video
(http://openstaxcollege.org/l/MRI) to learn more about MRIs. What is the function of magnets in
an MRI?
Answer: The magnets induce tissue to emit radio signals that can show differences between
different types of tissue.
5. PET relies on radioactive substances administered several minutes before the scan. Watch this
video (http://openstaxcollege.org/l/PET) to learn more about PET. How is PET used in
chemotherapy?
Answer: PET scans can indicate how patients are responding to chemotherapy
REVIEW QUESTIONS
6. Which of the following specialties might focus on studying all of the structures of the ankle
and foot?
Answer: C. regional anatomy
7. A scientist wants to study how the body uses foods and fluids during a marathon run. This
scientist is most likely a(n) ________.
Answer: A. exercise physiologist
, Page |2
8. The smallest independently functioning biological unit of an organism is a(n) ________.
Answer: A. cell
9. A collection of similar tissues that performs a specific function is an ________.
Answer: A. organ
10. The body system responsible for structural support and movement is the ________.
Answer: D. skeletal system
11. Metabolism can be defined as the ________.
Answer: D. sum of all chemical reactions in an organism
12. Adenosine triphosphate (ATP) is an important molecule because it ________.
Answer: C. stores energy for use by body cells
13. Cancer cells can be characterized as “generic” cells that perform no specialized body
function. Thus cancer cells lack ________.
Answer: A. differentiation
14. Humans have the most urgent need for a continuous supply of ________.
Answer: C. oxygen
15. Which of the following statements about nutrients is true?
Answer: A. All classes of nutrients are essential to human survival.
16. C.J. is stuck in a car during a bitterly cold blizzard. CJ’s body responds to the cold by
________.
Answer: C. breaking down stored energy
17. After you eat lunch, nerve cells in your stomach respond to the distension (the stimulus)
resulting from the food. They relay this information to ________.
Answer: A. a control center
18. Stimulation of the heat-loss center causes ________.
Answer: C. sweat glands to increase their output
19. Which of the following is an example of a normal physiologic process that uses a positive
feedback loop?
Answer: B. childbirth
20. What is the position of the body when it is in the “normal anatomical position?”
Answer: D. None of the above
21. To make a banana split, you halve a banana into two long, thin, right and left sides along the
________.
Answer: C. midsagittal plane
22. The lumbar region is ________.
, Page |3
Answer: D. superior to the popliteal region
23. The heart is within the ________.
Answer: B. mediastinum
24. In 1901, Wilhelm Röntgen was the first person to win the Nobel Prize for physics. For what
discovery did he win?
Answer: D. X-rays
25. Which of the following imaging techniques would be best to use to study the uptake of
nutrients by rapidly multiplying cancer cells?
Answer: C. PET
26. Which of the following imaging studies can be used most safely during pregnancy?
Answer: C. ultrasound
27. What are two major disadvantages of MRI scans?
Answer: B. high cost and the need for shielding from the magnetic signals
CRITICAL THINKING QUESTIONS
28. Name at least three reasons to study anatomy and physiology.
Answer: An understanding of anatomy and physiology is essential for any career in the health
professions. It can also help you make choices that promote your health, respond appropriately to
signs of illness, make sense of health-related news, and help you in your roles as a parent,
spouse, partner, friend, colleague, and caregiver.
29. For whom would an appreciation of the structural characteristics of the human heart come
more easily: an alien who lands on Earth, abducts a human, and dissects his heart, or an anatomy
and physiology student performing a dissection of the heart on her very first day of class? Why?
Answer: A student would more readily appreciate the structures revealed in the dissection. Even
though the student has not yet studied the workings of the heart and blood vessels in her class,
she has experienced her heart beating every moment of her life, has probably felt her pulse, and
likely has at least a basic understanding of the role of the heart in pumping blood throughout her
body. This understanding of the heart’s function (physiology) would support her study of the
heart’s form (anatomy).
30. Name the six levels of organization of the human body
Answer: Chemical, cellular, tissue, organ, organ system, organism.
31. The ovaries and the testes are a part of which body system? Can these organs be members of
more than one organ system? Why or why not?
Answer: The ovaries and the testes are parts of the reproductive system. But they also secrete
hormones, as does the endocrine system, therefore ovaries and testes function within both the
endocrine and reproductive systems.
, Page |4
32. Explain why the smell of smoke when you are sitting at a campfire does not trigger alarm,
but the smell of smoke in your residence hall does.
Answer: When you are sitting at a campfire, your sense of smell adapts to the smell of smoke.
Only if that smell were to suddenly and dramatically intensify would you be likely to notice and
respond. In contrast, the smell of even a trace of smoke would be new and highly unusual in your
residence hall, and would be perceived as danger.
33. Identify three different ways that growth can occur in the human body.
Answer: Growth can occur by increasing the number of existing cells, increasing the size of
existing cells, or increasing the amount of non-cellular material around cells.
34. When you open a bottle of sparkling water, the carbon dioxide gas in the bottle form bubbles.
If the bottle is left open, the water will eventually “go flat.” Explain these phenomena in terms of
atmospheric pressure.
Answer: In a sealed bottle of sparkling water, carbon dioxide gas is kept dissolved in the water
under a very high pressure. When you open the bottle, the pressure of the gas above the liquid
changes from artificially high to normal atmospheric pressure. The dissolved carbon dioxide gas
expands, and rises in bubbles to the surface. When a bottle of sparkling water is left open, it
eventually goes flat because its gases continue to move out of solution until the pressure in the
water is approximately equal to atmospheric pressure.
35. On his midsummer trek through the desert, Josh ran out of water. Why is this particularly
dangerous?
Answer: The primary way that the body responds to high environmental heat is by sweating;
however, sweating requires water, which comes from body fluids, including blood plasma. If
Josh becomes dehydrated, he will be unable to sweat adequately to cool his body, and he will be
at risk for heat stroke as his blood pressure drops too much from the loss of water from the blood
plasma.
36. Identify the four components of a negative feedback loop and explain what would happen if
secretion of a body chemical controlled by a negative feedback system became too great.
Answer: The four components of a negative feedback loop are: stimulus, sensor, control center,
and effector. If too great a quantity of the chemical were excreted, sensors would activate a
control center, which would in turn activate an effector. In this case, the effector (the secreting
cells) would be adjusted downward.
37. What regulatory processes would your body use if you were trapped by a blizzard in an
unheated, uninsulated cabin in the woods?
Answer: Any prolonged exposure to extreme cold would activate the brain’s heat-gain center.
This would reduce blood flow to your skin, and shunt blood returning from your limbs away
from the digits and into a network of deep veins. Your brain’s heat-gain center would also
increase your muscle contraction, causing you to shiver. This increases the energy consumption
of skeletal muscle and generates more heat. Your body would also produce thyroid hormone and
epinephrine, chemicals that promote increased metabolism and heat production.
