D Streak. The student is scratching it on white paper to test the streak.
Answer:
Humans and apes represent divergent lines of evolution from a common ancestor.
Explanation:
That's why we say we are related to chimps or other primates.
I mean, there's plenty of differences between muscle and nerve cells. For one, they serve different functions. Nerve cells react and send stimuli rapidly through action potentials, functioning in the nervous system and allowing the brain to communicate with the rest of the body, while muscle cells allow muscles to move. Another difference is the structure of the cells, with nerve cells having dendrites, axons, and neurotransmitters to assist in the firing of action potentials. You're going to have to be a little more specific, I can't really help you any more with such a broad question.
Answer:
it increases oxygen levels and decrease carbon dioxide levels
