HESI A2
HESI A2 Anatomy and Physiology 2023
1. Which part of the eye is responsible for color vision?
- A. Cornea
- B. Iris
- C. Retina
- D. Lens
Correct answer: C
Rationale: The correct answer is option C: Retina. The retina contains photoreceptor cells, including cones that are responsible for color vision. Cones are sensitive to different wavelengths of light, allowing us to perceive and differentiate various colors. Choice A, Cornea, is the transparent outer layer of the eye that helps focus light. It does not play a direct role in color vision. Choice B, Iris, is the colored part of the eye that controls the size of the pupil and regulates the amount of light entering the eye. While it is essential for adjusting light levels, it is not directly involved in color vision. Choice D, Lens, is responsible for focusing light onto the retina. It helps to form clear images on the retina but does not play a role in color vision.
2. Which type of blood cell is responsible for carrying oxygen?
- A. Red blood cells
- B. White blood cells
- C. Platelets
- D. Plasma cells
Correct answer: A
Rationale: The correct answer is A: Red blood cells. Red blood cells, also known as erythrocytes, are specialized cells designed to transport oxygen from the lungs to tissues and organs throughout the body. These cells contain hemoglobin, a protein that binds to oxygen molecules in the lungs and releases them in other parts of the body where oxygen is needed for cellular respiration. White blood cells (choice B) are part of the immune system, responsible for fighting infections. Platelets (choice C) are involved in blood clotting. Plasma cells (choice D) are a type of white blood cell that produces antibodies to help the body fight off infections.
3. What is the primary function of the cardiovascular system?
- A. To pump blood throughout the body
- B. To deliver nutrients to tissues
- C. To regulate body temperature
- D. To protect the body from infection
Correct answer: A
Rationale: The primary function of the cardiovascular system is to pump blood throughout the body, ensuring that oxygen and nutrients are delivered to tissues while removing waste products. This circulation is essential for maintaining overall health and proper functioning of the body's cells and organs. Choices B, C, and D are incorrect because while the cardiovascular system does deliver nutrients to tissues indirectly by transporting them in the blood, regulating body temperature is primarily the role of the endocrine and nervous systems, and protecting the body from infection is the main function of the immune system.
4. Which hormone is produced by the thyroid gland?
- A. Insulin
- B. Thyroxine
- C. Glucagon
- D. Cortisol
Correct answer: B
Rationale: Thyroxine is the hormone produced by the thyroid gland. It plays a crucial role in regulating metabolism, heart rate, and growth. Insulin is produced by the pancreas to regulate blood sugar levels, not by the thyroid gland. Glucagon is also produced by the pancreas and helps increase blood sugar levels. Cortisol is produced by the adrenal glands and is involved in stress response and metabolism, not by the thyroid gland.
5. What is the primary function of the kidneys in the urinary system?
- A. Regulating blood pressure
- B. Filtering blood to remove waste
- C. Producing red blood cells
- D. Regulating electrolyte balance
Correct answer: B
Rationale: The primary function of the kidneys in the urinary system is to filter blood to remove waste products and excess fluids, which are then excreted as urine. Kidneys act as a filtration system, removing waste like urea, excess salts, and toxins. While the kidneys do play a role in regulating blood pressure by secreting renin and maintaining electrolyte balance by adjusting the levels of sodium, potassium, and other ions in the blood, their main and essential function is filtration and waste removal, making choice B the correct answer.
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