CNA Chapter 4 Exam Questions and
Revised Answers () 100%
Guarantee Pass
CNA Chapter 4: Body Systems and Related Conditions
Q1. Which anatomical term means “toward the midline of the body”?
A. Lateral
B. Proximal
C. Medial
D. Posterior
Correct Answer: C. Medial
Rationale: Medial refers to a position closer to the midline of the body. Lateral means toward the
side, proximal means closer to the point of attachment, and posterior means toward the back.
Q2. Which anatomical term means “the front of the body”?
A. Anterior
B. Inferior
C. Superior
D. Posterior
Correct Answer: A. Anterior
Rationale: Anterior describes the front surface of the body. Posterior refers to the back, superior
means above, and inferior means below.
Q3. How many bones are in the human body?
A. 154
B. 189
C. 206
D. 272
Correct Answer: C. 206
Rationale: The adult human skeleton consists of 206 bones. This number is standard anatomical
knowledge and is frequently tested on CNA exams.
Q4. Which of the following is true of muscles?
A. They provide movement of body parts
B. Two muscles meet at a joint
C. They produce toxins
D. They prevent contractures from occurring
Correct Answer: A. They provide movement of body parts
pg. 1
,Rationale: Muscles are responsible for movement, posture, and heat production. Bones meet at
joints, not muscles. Muscles do not produce toxins. Contractures are prevented by range of motion,
not by muscles themselves.
Q5. Homeostasis is best defined as:
A. The condition in which all body systems are working their best
B. The breakdown of muscle tissue
C. The process of breathing
D. An autoimmune response
Correct Answer: A. The condition in which all body systems are working their best
Rationale: Homeostasis refers to a state of balance in which all body systems function optimally.
Atrophy is muscle wasting, respiration is breathing, and autoimmune responses involve the immune
system attacking normal tissue.
Q6. When atrophy occurs, what happens to the muscle?
A. It increases in size
B. It decreases in size
C. It becomes stronger
D. It produces more heat
Correct Answer: B. It decreases in size
Rationale: Atrophy is the wasting away or decrease in size of muscle tissue. It commonly occurs with
immobility and requires range of motion and activity to prevent or slow.
Q7. Which of the following statements is true of the skin?
A. It feels heat, cold, pain, touch, and pressure
B. It becomes more elastic as a person ages
C. It is the chemical substance that controls body functions
D. It becomes thicker as a person ages
Correct Answer: A. It feels heat, cold, pain, touch, and pressure
Rationale: The skin is a sense organ containing receptors for temperature, pain, touch, and pressure.
As a person ages, skin becomes less elastic and thinner, not more elastic or thicker.
Q8. One way a nursing assistant can help with normal changes of aging related to the integumentary
system is to:
A. Withhold fluids so a resident will not go to the bathroom often
B. Clip toenails frequently
C. Keep sheets wrinkle-free
D. Rub lotion into red or irritated spots on the resident’s skin
Correct Answer: C. Keep sheets wrinkle-free
Rationale: Wrinkle-free sheets reduce friction and shear, helping prevent skin breakdown in older
adults whose skin is thinner and more fragile. Withholding fluids is dangerous, nail clipping is
typically outside CNA scope, and massaging reddened areas can cause further damage.
Q9. Which of the following is a function of the nervous system?
A. It supplies food, oxygen, and hormones to cells
B. It helps the body take in oxygen and remove carbon dioxide
pg. 2
, C. It senses and interprets information from outside the body
D. It helps the body digest food
Correct Answer: C. It senses and interprets information from outside the body
Rationale: The nervous system controls and coordinates body functions and senses and interprets
internal and external information. Circulatory supplies nutrients, respiratory handles oxygen and
carbon dioxide, and gastrointestinal digests food.
Q10. The eye and ear are part of which body system?
A. Circulatory
B. Nervous
C. Respiratory
D. Integumentary
Correct Answer: B. Nervous
Rationale: The eye and ear are sense organs that feed information to the nervous system for
interpretation and response. They are considered part of the nervous system.
Q11. Which of the following is a function of the circulatory system?
A. It senses and interprets information
B. It supplies food, oxygen, and hormones to cells
C. It produces hormones that control body functions
D. It protects the body from disease
Correct Answer: B. It supplies food, oxygen, and hormones to cells
Rationale: The circulatory system, consisting of the heart and blood vessels, transports oxygen,
nutrients, hormones, and other substances to cells throughout the body.
Q12. The respiratory system is made up of which structures?
A. Heart, arteries, veins
B. Trachea, bronchi, lungs
C. Kidneys, bladder, ureters
D. Stomach, intestines, liver
Correct Answer: B. Trachea, bronchi, lungs
Rationale: The respiratory system includes the nose, pharynx, larynx, trachea, bronchi, and lungs. Its
primary function is to bring oxygen into the body and remove carbon dioxide.
Q13. Respiration consists of which two processes?
A. Systole and diastole
B. Inspiration and expiration
C. Digestion and absorption
D. Filtration and elimination
Correct Answer: B. Inspiration and expiration
Rationale: Respiration involves inspiration (breathing in) and expiration (breathing out). Systole and
diastole refer to heart function.
pg. 3
Revised Answers () 100%
Guarantee Pass
CNA Chapter 4: Body Systems and Related Conditions
Q1. Which anatomical term means “toward the midline of the body”?
A. Lateral
B. Proximal
C. Medial
D. Posterior
Correct Answer: C. Medial
Rationale: Medial refers to a position closer to the midline of the body. Lateral means toward the
side, proximal means closer to the point of attachment, and posterior means toward the back.
Q2. Which anatomical term means “the front of the body”?
A. Anterior
B. Inferior
C. Superior
D. Posterior
Correct Answer: A. Anterior
Rationale: Anterior describes the front surface of the body. Posterior refers to the back, superior
means above, and inferior means below.
Q3. How many bones are in the human body?
A. 154
B. 189
C. 206
D. 272
Correct Answer: C. 206
Rationale: The adult human skeleton consists of 206 bones. This number is standard anatomical
knowledge and is frequently tested on CNA exams.
Q4. Which of the following is true of muscles?
A. They provide movement of body parts
B. Two muscles meet at a joint
C. They produce toxins
D. They prevent contractures from occurring
Correct Answer: A. They provide movement of body parts
pg. 1
,Rationale: Muscles are responsible for movement, posture, and heat production. Bones meet at
joints, not muscles. Muscles do not produce toxins. Contractures are prevented by range of motion,
not by muscles themselves.
Q5. Homeostasis is best defined as:
A. The condition in which all body systems are working their best
B. The breakdown of muscle tissue
C. The process of breathing
D. An autoimmune response
Correct Answer: A. The condition in which all body systems are working their best
Rationale: Homeostasis refers to a state of balance in which all body systems function optimally.
Atrophy is muscle wasting, respiration is breathing, and autoimmune responses involve the immune
system attacking normal tissue.
Q6. When atrophy occurs, what happens to the muscle?
A. It increases in size
B. It decreases in size
C. It becomes stronger
D. It produces more heat
Correct Answer: B. It decreases in size
Rationale: Atrophy is the wasting away or decrease in size of muscle tissue. It commonly occurs with
immobility and requires range of motion and activity to prevent or slow.
Q7. Which of the following statements is true of the skin?
A. It feels heat, cold, pain, touch, and pressure
B. It becomes more elastic as a person ages
C. It is the chemical substance that controls body functions
D. It becomes thicker as a person ages
Correct Answer: A. It feels heat, cold, pain, touch, and pressure
Rationale: The skin is a sense organ containing receptors for temperature, pain, touch, and pressure.
As a person ages, skin becomes less elastic and thinner, not more elastic or thicker.
Q8. One way a nursing assistant can help with normal changes of aging related to the integumentary
system is to:
A. Withhold fluids so a resident will not go to the bathroom often
B. Clip toenails frequently
C. Keep sheets wrinkle-free
D. Rub lotion into red or irritated spots on the resident’s skin
Correct Answer: C. Keep sheets wrinkle-free
Rationale: Wrinkle-free sheets reduce friction and shear, helping prevent skin breakdown in older
adults whose skin is thinner and more fragile. Withholding fluids is dangerous, nail clipping is
typically outside CNA scope, and massaging reddened areas can cause further damage.
Q9. Which of the following is a function of the nervous system?
A. It supplies food, oxygen, and hormones to cells
B. It helps the body take in oxygen and remove carbon dioxide
pg. 2
, C. It senses and interprets information from outside the body
D. It helps the body digest food
Correct Answer: C. It senses and interprets information from outside the body
Rationale: The nervous system controls and coordinates body functions and senses and interprets
internal and external information. Circulatory supplies nutrients, respiratory handles oxygen and
carbon dioxide, and gastrointestinal digests food.
Q10. The eye and ear are part of which body system?
A. Circulatory
B. Nervous
C. Respiratory
D. Integumentary
Correct Answer: B. Nervous
Rationale: The eye and ear are sense organs that feed information to the nervous system for
interpretation and response. They are considered part of the nervous system.
Q11. Which of the following is a function of the circulatory system?
A. It senses and interprets information
B. It supplies food, oxygen, and hormones to cells
C. It produces hormones that control body functions
D. It protects the body from disease
Correct Answer: B. It supplies food, oxygen, and hormones to cells
Rationale: The circulatory system, consisting of the heart and blood vessels, transports oxygen,
nutrients, hormones, and other substances to cells throughout the body.
Q12. The respiratory system is made up of which structures?
A. Heart, arteries, veins
B. Trachea, bronchi, lungs
C. Kidneys, bladder, ureters
D. Stomach, intestines, liver
Correct Answer: B. Trachea, bronchi, lungs
Rationale: The respiratory system includes the nose, pharynx, larynx, trachea, bronchi, and lungs. Its
primary function is to bring oxygen into the body and remove carbon dioxide.
Q13. Respiration consists of which two processes?
A. Systole and diastole
B. Inspiration and expiration
C. Digestion and absorption
D. Filtration and elimination
Correct Answer: B. Inspiration and expiration
Rationale: Respiration involves inspiration (breathing in) and expiration (breathing out). Systole and
diastole refer to heart function.
pg. 3