Chemical substances secreted by cells into the extracellular fluids that regulate the metabolic function of other cells in the body are called ________.
- A. enzymes
- B. antibodies
- C. proteins
- D. hormones
Correct Answer: D
Rationale: The correct answer is D: hormones. Hormones are chemical substances secreted by cells into extracellular fluids to regulate metabolic functions in other cells. They act as messengers, traveling through the bloodstream to target tissues. Enzymes (A) are catalysts that accelerate chemical reactions. Antibodies (B) are proteins produced by the immune system to neutralize pathogens. Proteins (C) are essential macromolecules for various cellular functions but do not specifically regulate metabolic functions in other cells like hormones do.
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You are providing care for a patient who underwent thyroidectomy 2 days ago. Which laboratory value requires close monitoring?
- A. Calcium
- B. Sodium
- C. Potassium
- D. White blood cells
Correct Answer: A
Rationale: Calcium levels should be closely monitored after a thyroidectomy due to the risk of hypocalcemia caused by damage or removal of the parathyroid glands.
Effects of Hypothyroidism Include All but This
- A. Diarrhoea
- B. Lethargy
- C. Anorexia
- D. Weight gain
Correct Answer: A
Rationale: The correct answer is A: Diarrhoea. Hypothyroidism is associated with decreased metabolic function, leading to symptoms such as lethargy, anorexia, and weight gain. Diarrhoea is not typically a symptom of hypothyroidism; instead, it can be seen in conditions like hyperthyroidism where there is an excess of thyroid hormone. In hypothyroidism, the digestive processes slow down, which can lead to constipation rather than diarrhoea. Therefore, the effects of hypothyroidism do not include diarrhoea.
Which of the following is NOT a gland in the endocrine system?
- A. Adrenal gland
- B. Thyroid gland
- C. Kidney gland
- D. Pituitary gland
Correct Answer: C
Rationale: The correct answer is C: Kidney gland. The endocrine system consists of glands that secrete hormones directly into the bloodstream to regulate various bodily functions. The kidney is not a gland; it is an organ responsible for filtering waste from the blood and producing urine. The adrenal gland, thyroid gland, and pituitary gland are all part of the endocrine system as they secrete hormones. In summary, the kidney does not secrete hormones and therefore is not considered a gland in the endocrine system.
Steroid hormones exert their action by ________.
- A. entering the nucleus of a cell and initiating or altering the expression of a gene
- B. finding an appropriate cell receptor and initiating cAMP activity
- C. stimulating the synthesis of a glycogen
- D. increasing blood pressure
Correct Answer: A
Rationale: The correct answer is A because steroid hormones are lipid-soluble molecules that can pass through the cell membrane and bind to intracellular receptors in the nucleus. This binding activates or inhibits gene transcription, leading to changes in protein synthesis and cellular responses. Choice B is incorrect because cAMP activity is typically associated with peptide hormones, not steroid hormones. Choice C is incorrect because steroid hormones do not stimulate glycogen synthesis. Choice D is incorrect because steroid hormones do not directly affect blood pressure regulation.
What is the half-life of the isotope?
- A. 80s
- B. 100s
- C. 200s
- D. 2400s
Correct Answer: A
Rationale: The correct answer is A (80s) because the half-life of an isotope is the time taken for half of the radioactive nuclei to decay. In this case, it takes 80 seconds for half of the nuclei to decay. The other choices (B, C, D) are incorrect as they do not represent the correct time interval required for half of the nuclei to decay.