CNA Anatomy and Physiology Basics 3

Question 1

A CNA is performing range-of-motion exercises for a resident with a contracture in his hand. What is the underlying physiological reason for the contracture's resistance to movement?

Accepted Answer

Inelastic, fibrous tissue has replaced elastic muscle tissue.

Answer

A contracture is the chronic loss of joint mobility caused by structural changes in non-bony tissues like muscles, tendons, and ligaments. [16] During periods of immobility, elastic tissues can be replaced by inelastic, fibrous tissues, leading to shortening, hardening, and stiffness that restricts movement. [12, 20]

Question 2

A resident who rarely goes outside and has a diet low in fortified milk is at an increased risk for bone fractures. This is primarily because lack of sun exposure directly impairs the skin's ability to produce which vitamin, essential for calcium absorption?

Accepted Answer

Vitamin D

Answer

The skin synthesizes Vitamin D when exposed to ultraviolet (UVB) sunlight. [24] Vitamin D is crucial for the absorption of calcium from the intestines. Without sufficient Vitamin D, the body cannot absorb enough calcium, which can lead to weakened bones and an increased risk of fractures. [8, 26]

Question 3

A CNA is caring for a resident with significant swelling (edema) in their left leg. While the circulatory system is involved, which other body system's primary failure leads to this accumulation of excess interstitial fluid?

Accepted Answer

Lymphatic system

Answer

A key function of the lymphatic system is to collect excess fluid, proteins, and other substances from the body's tissues (interstitial fluid) and return it to the bloodstream. [3, 30] When this system is not working correctly, the fluid can build up in the tissues, causing swelling, a condition known as lymphedema. [27]

Question 4

A CNA observes that a resident, who is normally calm, suddenly becomes extremely anxious, with a rapid pulse, pale skin, and sweating. These signs are part of the 'fight or flight' response, which is triggered by hormones released from which endocrine gland?

Accepted Answer

Adrenal glands

Answer

The adrenal glands, specifically the adrenal medulla, release hormones like adrenaline (epinephrine) and noradrenaline (norepinephrine) in response to stress. [21, 33] These hormones cause the classic 'fight or flight' symptoms: increased heart rate, elevated blood pressure, sweating, and paleness as blood is redirected to major muscles. [22, 34]

Question 5

The care plan for a resident with a pressure ulcer on their sacrum states: 'Wound is 3 cm superior to the gluteal cleft.' To understand this, the CNA must recognize that 'superior' is a directional term related to which anatomical plane?

Accepted Answer

Transverse (horizontal) plane

Answer

The transverse, or horizontal, plane divides the body into superior (upper) and inferior (lower) portions. [14, 23] The term 'superior' means 'toward the head' or 'upper part of a structure,' indicating the wound is located above the gluteal cleft when viewing the body as divided by this horizontal plane.

CNA Practice Test

CNA Practice Test

CNA Anatomy and Physiology Basics 3