which of the following epithelial types is correctly matched with its major function

HESI A2

Anatomy HESI A2

1. Which of the following epithelial types is correctly matched with its major function?

A. Simple squamous epithelium – diffusion
B. Stratified squamous epithelium – protection
C. Stratified squamous epithelium – diffusion
D. Simple columnar epithelium – secretion or absorption

Correct answer: D

Rationale: The correct answer is D. Simple columnar epithelium is indeed primarily responsible for secretion and absorption due to its tall shape and presence of microvilli, which increase surface area for these functions. Simple squamous epithelium is mainly involved in diffusion, allowing for the exchange of gases or nutrients. Stratified squamous epithelium functions more for protection against mechanical stress and pathogens, as it forms a tough, protective barrier due to its many layers.

2. Which type of joint is found in the neck and allows for rotational movement?

A. Hinge joint
B. Pivot joint
C. Ball and socket joint
D. Saddle joint

Correct answer: B

Rationale: The correct answer is B: Pivot joint. A pivot joint, like the one found in the neck, allows for rotational movement, enabling the head to turn from side to side. Hinge joints (Choice A) allow movement in one plane like a door hinge and are not found in the neck. Ball and socket joints (Choice C) allow for a wide range of motion in multiple directions and are typically found in the hip and shoulder. Saddle joints (Choice D) allow for movement back and forth and side to side, like the thumb joint, but are not found in the neck.

3. Which vitamin is essential for the maintenance of healthy skin?

A. Vitamin A
B. Vitamin C
C. Vitamin D
D. Vitamin K

Correct answer: A

Rationale: Vitamin A is the correct answer. It is crucial for maintaining healthy skin as it supports skin cell growth, repair, and overall skin health. Additionally, vitamin A plays a role in vision and immune function. Deficiency in vitamin A can lead to skin issues such as dryness and poor wound healing. Vitamin C is known for its role in collagen synthesis and antioxidant properties, while Vitamin D is important for bone health and immunity. Vitamin K is essential for blood clotting, but it is not primarily associated with skin health.

4. Which is a secondary defense for the body against pathogens?

A. Tears
B. Urine
C. Inflammation
D. Mucus

Correct answer: C

Rationale: Inflammation is a secondary defense mechanism for the body against pathogens. When tissues are injured or infected, inflammation occurs as a protective response involving increased blood flow, white blood cell migration, and tissue repair. This process helps contain and eliminate pathogens, preventing them from spreading further in the body. Tears (Choice A) are a primary defense containing lysozyme and other antimicrobial agents. Urine (Choice B) is typically considered a non-specific defense mechanism due to its flushing action in the urinary tract. Mucus (Choice D) acts as a physical barrier and traps pathogens, also considered a primary defense mechanism.

5. What is the function of white blood cells?

A. To carry oxygen to the cells
B. To fight infection
C. To transport nutrients
D. To clot blood

Correct answer: B

Rationale: White blood cells are a vital part of the immune system. Their primary function is to fight infections by attacking bacteria, viruses, and other pathogens that enter the body. They play a crucial role in protecting the body against illnesses and maintaining overall health. Choice A is incorrect because the role of carrying oxygen to cells is primarily performed by red blood cells. Choice C is incorrect as the transportation of nutrients is mainly carried out by the bloodstream and specialized cells. Choice D is incorrect as the process of clotting blood is primarily mediated by platelets.