Describe how lipophilic hormones are transported
What will be an ideal response?
Lipophilic steroids and thyroid hormone, which are poorly soluble in water, cannot dissolve to any extent in the watery blood. Instead, most lipophilic hormones circulate to their target cells reversibly bound to plasma proteins in the blood. Some plasma proteins carry only one type of hormone, whereas others, such as albumin, indiscriminately pick up any "hitchhiking" hormone. Only the small, unbound, freely dissolved fraction of a lipophilic hormone is biologically active. The bound form of steroid and thyroid hormones provides a large reserve of these lipophilic hormones that can be used to replenish the active free pool. To maintain normal endocrine function, the magnitude of the small, free, effective pool, rather than the total blood concentration of a particular lipophilic hormone, is monitored and adjusted.
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Explain why the sympathetic division of the ANS has more widespread and longer-lasting effects than the parasympathetic division
What will be an ideal response
The ________ duct empties into the vestibule at the level of the second upper molar.
A) submaxillary B) submandibular C) parotid D) sublingual E) vestibular
Which of the following are associated with the sense of touch?
A. Tactile cells B. Fibroblasts C. Keratinocytes D. Melanocytes E. Dendritic cells
Reflux of gastric contents into the esophagus occurs because of
A. relaxation of the cardiac sphincter. B. contraction of the pyloric sphincter. C. spasms of the submucosal layer of the stomach wall. D. increased hydrochloric acid production by the parietal cells. E. increased amounts of mucous produced by the stomach.