The diagram below shows the results of a northern blot analysis that tested for the expression of four peptide hormones in two endocrine tissues. The endocrine glands that most likely correspond to tissues A and B are the:

Question

The diagram below shows the results of a northern blot analysis that tested for the expression of four peptide hormones in two endocrine tissues.  The endocrine glands that most likely correspond to tissues A and B are the:

Quizplus · Accepted Answer

11ecba2d_1015_51d5_a3bf_7567dc3e3012_MD0008_00 The endocrine system modulates physiological activity via the secretion of hormones, which travel through the bloodstream and bind receptors in target tissues to elicit specific responses. The following are examples of endocrine glands: The anterior lobe of the pituitary gland secretes several hormones, including thyroid-stimulating hormone (TSH), luteinizing hormone (LH), follicle-stimulating hormone (FSH), adrenocorticotropic hormone (ACTH), and growth hormone (GH). Specifically, GH promotes processes such as tissue growth and utilization of fats. In addition, pituitary release of LH and FSH regulates reproductive function in males and females. In females, FSH and LH stimulate follicle maturation, ovulation, and estrogen production. In males, spermatogenesis and testosterone production are regulated by FSH and LH, respectively. The pancreas regulates blood glucose concentration by secreting insulin and glucagon. Insulin is secreted in response to high blood glucose levels to promote glycogen formation in the liver and uptake of glucose by cells. In contrast, glucagon is secreted in response to low glucose levels to promote gluconeogenesis and glycogen breakdown. In the given scenario, northern blotting was used to test mRNA expression in two endocrine tissues. The results show that tissue A (the pancreas) expresses insulin and glucagon, and tissue B (the anterior pituitary) expresses GH and LH. (Choice A) This scenario is reversed; the pancreas does not secrete LH and GH, and the pituitary gland does not secrete insulin and glucagon. (Choices C and D) The adrenal glands secrete hormones that modulate the physiological stress response, and the hypothalamus secretes several hormones (eg, GRH, GnRH) that regulate release of pituitary hormones. However, neither of these endocrine glands secrete the hormones shown in the northern blot. Educational objective: Endocrine glands modulate physiological activity via the secretion of hormones. For example, the pancreas secretes insulin and glucagon to regulate blood glucose levels. In contrast, the anterior lobe of the pituitary gland secretes multiple hormones that regulate several processes, including metabolism and reproductive function.

The Diagram Below Shows the Results of a Northern Blot