HESI A2
HESI A2 Anatomy and Physiology 2023
1. Which type of blood cell is primarily responsible for fighting infections?
- A. Red blood cells
- B. White blood cells
- C. Platelets
- D. Plasma
Correct answer: B
Rationale: White blood cells, also known as leukocytes, play a crucial role in the immune system by primarily combating infections. These cells can identify and destroy pathogens, such as bacteria and viruses, helping the body defend against illnesses and maintain overall health. Red blood cells are responsible for oxygen transport, platelets aid in blood clotting, and plasma carries various components throughout the circulatory system, but none of these functions involve fighting infections like white blood cells do.
2. What is the function of the urinary bladder?
- A. To filter waste from the blood
- B. To store urine
- C. To regulate fluid balance
- D. To remove waste from the body
Correct answer: B
Rationale: The correct answer is B: To store urine. The urinary bladder's primary function is to store urine produced by the kidneys until it is ready to be excreted from the body. It acts as a reservoir that temporarily holds urine until an appropriate time for elimination. Choices A, C, and D are incorrect because the urinary bladder does not filter waste from the blood, regulate fluid balance, or directly remove waste from the body. These functions are primarily carried out by the kidneys and other organs in the excretory system.
3. Which hormone is released by the adrenal medulla?
- A. Cortisol
- B. Adrenaline
- C. Insulin
- D. Somatostatin
Correct answer: B
Rationale: The correct answer is B, Adrenaline (also known as epinephrine), which is released by the adrenal medulla during the body's fight-or-flight response. Adrenaline helps prepare the body for action by increasing heart rate, dilating air passages, and mobilizing glucose and fats for energy, among other physiological responses. Choice A, Cortisol, is a steroid hormone released by the adrenal cortex involved in the stress response and regulation of metabolism. Choice C, Insulin, is produced by the pancreas and regulates blood sugar levels. Choice D, Somatostatin, is a hormone that inhibits the release of several other hormones in the body, but it is not released by the adrenal medulla.
4. Which bone does not articulate with any other bone?
- A. Femur
- B. Hyoid
- C. Radius
- D. Tibia
Correct answer: B
Rationale: The correct answer is the Hyoid bone. The hyoid bone is distinctive as it does not directly articulate with any other bone in the body. Instead, it is held in place by muscles and ligaments, playing a crucial role in supporting the tongue and providing attachment points for various muscles involved in swallowing and speech. The other choices, Femur, Radius, and Tibia, all articulate with other bones in the body. The femur articulates with the hip bone, the radius articulates with the ulna and other bones in the wrist, and the tibia articulates with the femur and fibula.
5. 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.
Similar Questions
Access More Features
HESI A2 Basic
$99/ 30 days
- 3,000 Questions with answers
- 30 days access
HESI A2 Premium
$149.99/ 90 days
- Actual HESI A2 Questions
- 3,000 questions with answers
- 90 days access