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Behavioral responses in organisms require communication between
A.
an organism and its environment.
B.
an organism's cells and systems.
C.
one organism and another.
D.
an organism's cells and bacteria.

The eruption of a nearby volcano causes a prairie ecosystem to receive a lot less sunlight. which of these is most likely effect on the ecosystem?

Suppose you are provided with an actively dividing culture of e. coli bacteria to which radioactive thymine has been added. what would happen if a cell replicates once in the presence of this radioactive base?

Once an egg cell is fertilized by sperm, the cell then, as the embryo develops, it receives nourishment and eliminates wastes by transferring substances from its blood to its mother's blood. a. becomes a fetus immediately and exits the womb b. begins to divide and implants itself in the wall of the uterus c. remains in the uterus without dividing for several months d. travels back to the ovaries until the fetus is developed