Explain why the transport of molecules across the cell membrane is considered to be both specific and directional

What will be an ideal response?


ANSWER: Transport is considered directional because only certain ions and molecules can move into
the cell, while others can only move out of the cell. Transport is specific because only certain
ions and molecules can actually move across the membrane.

Biology & Microbiology

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Archaeopteris, the first known tree, has all of the following characteristics EXCEPT:

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Stool specimens suspected of containing which of the following enteric pathogens should be collected and transported only in Cary-Blair medium because buffered glycerol saline is toxic for this bacterium?

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Biology & Microbiology

Choose the function that best matches to each item.

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Biology & Microbiology

The distal convoluted tubule 

A. reabsorbs glucose. B. secretes water. C. increases the amount of protein in the nephron. D. regulates ions.

Biology & Microbiology