Why is it necessary for the stomach contents to be so acidic? How does the stomach protect itself from digestion?
What will be an ideal response?
HCl is necessary for the activation and optimal activity of pepsin, and it kills many of the bacteria ingested with food. Mucous cells in the lining of the stomach secrete an alkaline mucus that clings to the stomach wall and helps to shield it from the acid. The epithelial cells of the mucosa are joined together by tight junctions that prevent gastric juice from leaking into underlying tissue layers. Damaged epithelial cells are shed and quickly replaced by cell division.
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If all other conditions remain the same and the concentration of a nonpenetrating solute increases inside a cell, which is most likely to occur?
A. The solute will diffuse across the membrane until its concentration is equal on both sides of the membrane. B. Water will tend to leave the cell because the interior has a decreased osmolarity. C. Water will tend to enter the cell because the interior has a decreased osmolarity. D. Water will tend to leave the cell because the interior has an increased osmolarity. E. Water will tend to enter the cell because the interior has an increased osmolarity.
How does the skeletal system aid the cardiovascular system?
A. Red bone marrow produces RBCs B. Rib-cage protects the heart C. Stores calcium needed for blood clotting D. All apply.
Firefly, a female quarter horse, had a ______________________ lump that was located above the shoulder blade
Fill in the blank(s) with correct word
The myometrium is composed primarily of smooth muscle that thickens under the influence of estrogen
Indicate whether the statement is true or false