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
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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
a. Heating sample to obtain single-stranded target nucleic acid, hybridization of target to probe, detection of hybridization, labe-ling of probe b. Labeling of probe, heating sample to ob-tain single-stranded target nucleic acid, hybridization of target to probe, detection of hybridization c. Hybridization of target to probe, detection of hybridization, labeling of probe, heating sample to obtain single-stranded target nucleic acid d. Hybridization of target to probe, labeling of probe, heating sample to obtain sin-gle-stranded target nucleic acid, detection of hybridization
Ovulation typically occurs on day ____ of a 28-day ovarian cycle
a. 1 b. 7 c. 10 d. 14 e. 28
Which of the following vertebrates has a social structure most closely resembling social insects?
a. the phalarope b. lions c. the naked mole rats d. Siberian tigers e. chimpanzees
Insulin is synthesized in (A)____, and reduces (B)____ levels in the bloodstream.
a. (A) B cells (liver) (B) fatty acid b. (A)B cells (pancreas) (B) glucose c. (A) A cell (liver) (B) fatty acid d. (A) Acell (pancreas) (B) glucose