Loading of most carbohydrates produced by photosynthesis into companion cells at a source occurs by

a. osmosis.
b. proton pumping.
c. suction from unloading at a sink.
d. active transport.
e. diffusion of water from the xylem.


D

Biology & Microbiology

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Insulin is synthesized in (A)____, and reduces (B)____ levels in the bloodstream.

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Biology & Microbiology

Place the basic steps involved in a molecular hybridization assay in sequence from first to last in the order in which they would be performed

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Which of the following vertebrates has a social structure most closely resembling social insects?

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Biology & Microbiology