The fight-or-flight reaction prepares an animal to respond to a threatening situation, by either fighting or running away. One aspect of this response is changes in blood flow such that the skeletal muscles and heart receive higher blood flow (vessels dilate) while digestive organs receive less (vessels constrict). Which signal molecule(s) is/are involved in this response, and how do they produce
these changes in blood vessels? Explain how this example illustrates one or more of the following concepts: multiple ligands for one receptor, multiple receptors for one ligand, agonists and antagonists.
What will be an ideal response?
Stimulus: increased blood glucose. Integrating center: endocrine cell (in pancreas). Efferent pathway: insulin secretion. Response: increased cellular uptake of glucose. Feedback: negative. Stimulus: decreased blood glucose. Integrating center: endocrine cell (in pancreas). Efferent pathway: glucagon secretion. Response: release of glucose from cells. Feedback: negative.
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A ____________________________________ is a surgery to prevent bloating and twisting of the stomach because it surgically stabilizes the stomach to the abdominal wall
Fill in the blank(s) with correct word
The volume of air available for gas exchange per minute is called the ________.
A. vital capacity B. respiratory rate C. minute respiratory volume D. alveolar ventilation E. functional residual capacity
Regarding kidney function, in reabsorption,
A) solutes enter the tubular fluid after exiting the peritubular fluid and crossing the tubular epithelium. B) water and solutes are transported from the tubular fluid, across the tubular, epithelium, and into the peritubular fluid. C) blood pressure forces water and solutes across the membranes of the glomerular capillaries and into the capsular space.
Joe begins to experience mood swings and disturbed thirst and hunger. Imaging studies indicate that a brain tumor is the likely cause of these disorders. In what part of the brain is the tumor most likely located?
A) prefrontal cortex B) postcentral gyrus C) basal nuclei D) hypothalamus E) reticular formation