HESI A2
HESI A2 Anatomy and Physiology 2023
1. Which type of joint allows for movement in multiple directions?
- A. Hinge joint
- B. Ball and socket joint
- C. Pivot joint
- D. Saddle joint
Correct answer: B
Rationale: The correct answer is a ball and socket joint like the shoulder or hip joint, as it allows for movement in multiple directions, including rotation. This type of joint offers a high degree of mobility due to its structure, where the rounded end of one bone fits into the cup-like socket of another bone. A hinge joint (Choice A) allows movement primarily in one plane, like the elbow or knee. A pivot joint (Choice C) allows for rotation around an axis, seen in the neck joint. A saddle joint (Choice D) enables movements in multiple directions but to a lesser extent compared to a ball and socket joint, found in the thumb joint.
2. Which vitamin is essential for blood clotting?
- A. Vitamin C
- B. Vitamin K
- C. Vitamin D
- D. Vitamin B12
Correct answer: B
Rationale: Vitamin K is essential for blood clotting as it is necessary for the synthesis of proteins involved in the coagulation process, such as clotting factors. Without sufficient Vitamin K, the blood may not clot properly, leading to excessive bleeding. Vitamin C is important for collagen synthesis and immune function, Vitamin D is essential for calcium absorption and bone health, and Vitamin B12 is crucial for red blood cell formation and neurological function. However, when it comes to blood clotting, Vitamin K plays a vital role.
3. Which of the following structures regulates the transport of substances in and out of a cell?
- A. Nucleus
- B. Cell membrane
- C. Cytoplasm
- D. Mitochondria
Correct answer: B
Rationale: The cell membrane, also known as the plasma membrane, is responsible for regulating the transport of substances in and out of the cell. It acts as a selective barrier, allowing the passage of certain molecules while restricting others. This selective permeability helps maintain homeostasis within the cell by controlling the movement of essential substances like nutrients and waste products. The nucleus (Choice A) is the organelle that houses the cell's genetic material and is not directly involved in regulating substance transport. Cytoplasm (Choice C) is the gel-like substance that fills the cell and does not play a direct role in regulating substance transport. Mitochondria (Choice D) are responsible for energy production in the cell through cellular respiration and are not primarily involved in substance transport.
4. Which type of blood vessel carries deoxygenated blood back to the heart?
- A. Arteries
- B. Capillaries
- C. Veins
- D. Lymphatic vessels
Correct answer: C
Rationale: Veins are the blood vessels that carry deoxygenated blood from the body's tissues back to the heart. Deoxygenated blood is transported from the body to the heart through veins, while arteries carry oxygenated blood away from the heart. Capillaries facilitate the exchange of nutrients and gases between the blood and tissues. Lymphatic vessels are responsible for returning excess tissue fluid to the bloodstream and do not primarily carry deoxygenated blood.
5. Which type of muscle tissue is found in the walls of hollow organs?
- A. Skeletal muscle
- B. Cardiac muscle
- C. Smooth muscle
- D. Striated muscle
Correct answer: C
Rationale: Smooth muscle tissue is found in the walls of hollow organs such as the intestines, blood vessels, and bladder. It contracts involuntarily, allowing for functions like peristalsis in the intestines and regulation of blood flow in blood vessels. Skeletal muscle (Choice A) is attached to bones, cardiac muscle (Choice B) is found in the heart, and striated muscle (Choice D) refers to both skeletal and cardiac muscles due to their striped appearance, but neither of these types are typically found in the walls of hollow organs.
Similar Questions
Access More Features
HESI A2 Basic
$49/ 30 days
- 3,000 Questions with answers
- 30 days access
HESI A2 Premium
$99/ 90 days
- Actual HESI A2 Questions
- 3,000 questions with answers
- 90 days access