To prevent blood flowing back after each heartbeat. They ensure that the blood flows only in one direction (back to the heart).
Answer:
D.-
Explanation:
A control group is needed to carry out the experiment, that control group is the one that is not injected with anything. Ethanol and pesticide need to be injected into separated groups to document whether it is one or the other that is harmful
It would cause the cell membrane to "pop" like a balloon. b the cell would not be able to get enough of the gases and nutrients it needed. c the cell could not be part of a small organism, such as a mouse. d there would not be enough resources in the cell's environment to feed it.
Answer:
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