Describe the inward forces of elastic recoil, and explain why the lungs do not normally collapse during expiration
What will be an ideal response
Elastic recoil is the recoil of elastic fibers stretched during inspiration and the pull of the surface tension of alveolar fluid. Intrapleural pressure is always subatmospheric during normal breathing, which tends to pull lungs outward and to keep alveolar pressure from equalizing with atmospheric pressure. Surfactant in alveolar fluid decreases surface tension to help prevent collapse.
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How many years are many states required to keep medical records?
a. 10 years c. 5 years b. 7 years d. 3 years
Which of the following are paired correctly?
a. Parafollicular cells (C cells) in thyroid gland / calcitonin b. Parathyroid gland / thyroid hormone c. Thyroid gland / PTH d. Pancreatic beta cells / glucagon e. Pancreatic alpha cells / Insulin f. Adrenal glands / epinephrine and norepinephrine
Mucus secreted by mucous membranes mainly serves as a protection against
A. excessive sugar absorption. B. cold and hot. C. viruses and bacteria. D. trauma.
Which of the following statements about humoral immunity is false?
A. Humoral immunity is also called cell-mediated immunity. B. Humoral immunity begins when an APC in lymphoid tissue displays an epitope from its environment on an MHC protein. C. Plasma B cells produce specific antibodies. D. Humoral immunity involves B cells making antibodies.