Exam 1 Wiley Plus Checkpoints Questions and Answers with Complete Solutions

Exam 1 Wiley Plus Checkpoints Questions and Answers with Complete Solutions List the similarities among and differences between the nervous and endocrine systems with regard to the control of homeostasis. - answer What is the basic difference between endocrine glands and exocrine glands - answerSecretions of endocrine glands diffuse into interstitial fluid and then into the blood; exocrine secretions flow into ducts that lead into body cavities or to the body surface. List three organs or tissues that are not exclusively classified as endocrine glands but contain cells that secrete hormones. - answerHypothalamus, thymus, pancreas, ovaries, testes, kidneys, stomach, liver, small intestine, skin, heart adipose tissue and placenta. In the stomach, one stimulus for secretion of hydrochloric acid by parietal cells is the release of histamine by neighboring mast cells. Is histamine an autocrine or a paracrine in this situation? - answerIn the stomach, histamine is a paracrine because it acts on nearby parietal cells without entering the blood. What is the difference between down-regulation and up-regulation - answerIf a cell increases the number of receptors then we call it up regulation; and if the cell decreases the number of receptors we call it down regulation. Up regulation is used by cells to increase their sensitivity to a specific hormone. Identify the chemical classes of hormones, and give an example of each. - answerSteroids - derived from cholesterol; estrogen, progesterone, testosterone, cortisol Peptides - oxytocin, ADH, CRH, PRH, GHRH, GnRH, TRH, PIH, GHIH, ACTH, LH, GH, PRL, TSH, FSH Monoamines - dopamine, epinephrine, norepinephrine, melatonin, thyroid hormone How are hormones transported in the blood? - answerHormones synthesized by the endocrine glands are transported throughout the body by the bloodstream. At the target organ, they will diffuse into the interstitial fluid and initiate a response in cells which have receptors specific to the hormone. What is the action of the receptor-hormone complex? - answerThe receptor-hormone complex alters gene expression by turning specific genes of nuclear DNA on or off.