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 gland is responsible for regulating metabolism?
- A. Pituitary gland
- B. Adrenal gland
- C. Thyroid gland
- D. Pineal gland
Correct answer: C
Rationale: The thyroid gland is responsible for regulating metabolism. It produces hormones such as thyroxine, which plays a key role in influencing the body's metabolic rate. The pituitary gland is known as the 'master gland' but is not directly responsible for regulating metabolism. The adrenal gland is involved in the stress response and producing hormones like cortisol, not primarily regulating metabolism. The pineal gland produces melatonin, which regulates sleep-wake cycles, not metabolism. Therefore, the correct answer is the thyroid gland.
3. When an individual is under stress, hormones are released. Which of the following is not one of the locations in which hormones are released when under stress?
- A. Posterior pituitary
- B. Hypothalamus
- C. Adrenal cortex
- D. Parathyroid
Correct answer: D
Rationale: During stress, hormones are released from the adrenal cortex, posterior pituitary, and hypothalamus to help the body respond. The parathyroid gland, however, is not typically involved in the stress response by releasing hormones. The posterior pituitary releases hormones like oxytocin and vasopressin, the hypothalamus secretes corticotropin-releasing hormone (CRH) and vasopressin, while the adrenal cortex releases cortisol and aldosterone in response to stress. Therefore, the correct answer is 'Parathyroid.'
4. Which hormone is released by the posterior pituitary gland?
- A. Oxytocin
- B. Thyroxine
- C. Insulin
- D. ADH
Correct answer: A
Rationale: Oxytocin is the correct answer. It is released by the posterior pituitary gland and plays a vital role in childbirth and lactation. Oxytocin promotes uterine contractions during labor and milk ejection during breastfeeding. Choice B, Thyroxine, is incorrect as it is produced by the thyroid gland. Choice C, Insulin, is incorrect as it is produced by the pancreas. Choice D, ADH (Antidiuretic Hormone), is also released by the posterior pituitary gland, but it is not the hormone primarily associated with childbirth and lactation.
5. What is the main function of the endocrine system?
- A. To fight infections
- B. To regulate body functions through hormones
- C. To produce red blood cells
- D. To transport oxygen
Correct answer: B
Rationale: The main function of the endocrine system is to regulate various body functions by releasing hormones, which act as chemical messengers. These hormones help maintain homeostasis, regulate metabolism, growth, development, and other essential functions in the body. Option A is incorrect as fighting infections is primarily the role of the immune system, not the endocrine system. Option C is incorrect as the production of red blood cells mainly occurs in the bone marrow. Option D is incorrect as the transportation of oxygen is primarily carried out by the respiratory and circulatory systems. Therefore, option B is the correct answer as it accurately describes the primary role of the endocrine system.
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