How do most polar molecules move through a cell membrane? Explain why water, a polar molecule, is able to cross the nonpolar portion of a cell membrane.
What will be an ideal response?
Most polar molecules must be assisted by a protein, because the molecule will not interact with the nonpolar phospholipid tails. Examples are facilitated diffusion and active transport. Because water is very small and electrically neutral, it is able to diffuse between the phospholipid tails.
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The two important urinary buffers are filtered phosphate buffers and secreted ____________________
Fill in the blank(s) with correct word
Which organs are associated with the dorsal cavity?
A. Lungs and heart B. Digestive organs C. Reproductive organs D. Brain and spinal cord
In order to stabilize the hyoid so that the larynx can be elevated in swallowing, the _____ muscle group is used
A. pterygoid B. infrahyoid C. auricularis D. suprahyoid E. hyoglossus