Nokea
Hormone release stops when the stimulus that triggered it – like thirst or high blood sugar is satisfied or corrected. This is called:
- A. positive feedback system
- B. negative feedback system
- C. lock and key system
- D. solar system
Correct Answer: B
Rationale: The correct answer is B: negative feedback system. In a negative feedback system, the body's response to a stimulus works to counteract the initial stimulus, bringing the body back to its set point. In the context of the question, hormone release stops when the stimulus is satisfied, which is characteristic of a negative feedback system. A: Positive feedback system amplifies the initial stimulus rather than counteracting it. C: Lock and key system refers to how enzymes bind to specific substrates, not related to hormone regulation. D: Solar system is unrelated to physiological processes.
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Which of the following is characterized by excess urine production resulting in low blood volume?
- A. Cushing syndrome
- B. Tetany
- C. Diabetes insipidus
- D. Oversecretion of ACTH
Correct Answer: C
Rationale: Correct Answer: C - Diabetes insipidus
Rationale:
1. Diabetes insipidus is characterized by excess urine production due to inadequate ADH secretion.
2. Low blood volume occurs as a result of increased urine output, leading to dehydration.
3. Cushing syndrome involves excess cortisol production, not excess urine production.
4. Tetany is caused by low calcium levels, not excess urine production.
5. Oversecretion of ACTH leads to excess cortisol production, not excess urine production.
Concerning physostigmine, which of the following is CORRECT:
- A. Is a natural quaternary ammonium compound
- B. Has no CNS action
- C. It is an irreversible anti-cholinesterase
- D. It is used in the treatment of glaucoma
Correct Answer: D
Rationale: The correct answer is D because physostigmine is used in the treatment of glaucoma due to its ability to lower intraocular pressure. It works by inhibiting the enzyme acetylcholinesterase, leading to increased levels of acetylcholine which helps in constricting the pupil and improving drainage of fluid in the eye. Options A and C are incorrect as physostigmine is a tertiary amine and a reversible anti-cholinesterase. Option B is incorrect as physostigmine does have CNS action, crossing the blood-brain barrier and affecting brain function.
A client is admitted to the hospital with Addison's disease. When discharging the client, the nurse reviews discharge instructions on nutrition. Which of the following discharge instructions are important for the client with Addison's disease regarding nutrition?
- A. Eat a diet high in protein, low in refined carbohydrates
- B. Consume two meals per day
- C. Eat foods high in potassium
- D. Drink less than 1 L of fluid per day
Correct Answer: A
Rationale: A diet high in protein and low in refined carbohydrates is important for clients with Addison's disease to support adrenal function and manage their condition.
Insulin enhances the membrane transport of glucose in all of the following tissues EXCEPT __________.
- A. the brain
- B. skeletal muscle
- C. the myocardium
- D. adipose tissue
Correct Answer: A
Rationale: Insulin enhances glucose transport by promoting the translocation of glucose transporter proteins to the cell membrane. The brain does not require insulin for glucose uptake as it has a specialized transporter. Skeletal muscle, myocardium, and adipose tissue all rely on insulin for increased glucose transport. Therefore, the correct answer is A. The other choices (B, C, and D) are incorrect as they all depend on insulin to enhance glucose transport in their respective tissues.
Exemplify hormones secreted by the anterior pituitary.
- A. anti-diuretic hormone and oxytocin
- B. ACTH and insulin
- C. growth hormone and LH
- D. thyroxine and cortisol
Correct Answer: C
Rationale: The correct answer is C: growth hormone and LH. The anterior pituitary gland secretes these hormones. Growth hormone regulates growth, metabolism, and body composition, while LH (luteinizing hormone) plays a role in reproductive function.
A: Anti-diuretic hormone and oxytocin are produced by the posterior pituitary gland.
B: ACTH (adrenocorticotropic hormone) is secreted by the anterior pituitary, but insulin is produced by the pancreas.
D: Thyroxine is released by the thyroid gland, and cortisol is produced by the adrenal glands, not the anterior pituitary.