HESI A2
Anatomy and Physiology Hesi A2 Practice Test
1. What is the main function of the immune system?
- A. To produce hormones
- B. To protect the body from infections
- C. To remove waste products
- D. To regulate body temperature
Correct answer: B
Rationale: The main function of the immune system is to protect the body from infections by identifying and destroying pathogens like bacteria and viruses. It plays a crucial role in maintaining overall health and preventing illnesses. Choice A is incorrect because hormone production is primarily handled by the endocrine system, not the immune system. Choice C is incorrect as waste removal is mainly performed by the excretory system, not the immune system. Choice D is incorrect as regulating body temperature is primarily the role of the thermoregulatory system, not the immune system.
2. Which hormone is involved in regulating the sleep-wake cycle?
- A. Insulin
- B. Melatonin
- C. Cortisol
- D. Thyroxine
Correct answer: B
Rationale: The correct answer is B: Melatonin. Melatonin, produced by the pineal gland, is the hormone involved in regulating the sleep-wake cycle. It plays a crucial role in signaling the body that it is time to sleep and is influenced by light exposure. Melatonin levels typically rise in the evening, promoting sleep, and decrease in the morning, helping in waking up. Choice A, Insulin, is involved in regulating blood sugar levels, not the sleep-wake cycle. Choice C, Cortisol, is a stress hormone that helps regulate metabolism and immune response but is not primarily involved in the sleep-wake cycle. Choice D, Thyroxine, is a hormone produced by the thyroid gland that regulates metabolism, growth, and development, but it is not directly involved in regulating the sleep-wake cycle.
3. What is the primary function of platelets?
- A. To fight infections
- B. To clot blood
- C. To carry oxygen
- D. To transport nutrients
Correct answer: B
Rationale: The primary function of platelets, or thrombocytes, is to clot blood. Platelets play a crucial role in hemostasis by forming clots to prevent excessive bleeding when injuries occur. They are not directly involved in fighting infections, carrying oxygen, or transporting nutrients. Therefore, the correct answer is B.
4. Which plane would you use to separate the abdominal cavity from the thoracic cavity?
- A. Sagittal
- B. Transverse
- C. Frontal
- D. Coronal
Correct answer: B
Rationale: The transverse plane, also known as the horizontal plane, runs horizontally from left to right, dividing the body into superior (upper) and inferior (lower) parts. This plane is ideal for separating the abdominal cavity (located below) from the thoracic cavity (located above). The sagittal plane (choice A) divides the body into left and right portions, the frontal plane (choice C) divides the body into front and back portions, and the coronal plane (choice D) is another term for the frontal plane. Therefore, when looking to separate the abdominal cavity from the thoracic cavity, the transverse plane is the most appropriate choice.
5. What is the primary hormone secreted by the thyroid gland?
- A. Oxytocin
- B. TSH
- C. Adrenaline
- D. T4
Correct answer: D
Rationale: The correct answer is D: T4. The primary hormone secreted by the thyroid gland is thyroxine, also known as T4. T4 plays a crucial role in regulating metabolism, growth, and energy levels in the body. It is converted into the more active form, triiodothyronine (T3), which exerts most of the biological effects of thyroid hormones. Choices A, B, and C are incorrect. Oxytocin is not produced by the thyroid gland but by the pituitary gland, TSH (thyroid-stimulating hormone) is secreted by the pituitary gland to stimulate the thyroid gland, and adrenaline is produced by the adrenal glands, not the thyroid gland.
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