Answer:
Your answer should be... Without them, complex organisms cannot perform different functions.
<span>
Basically because your skin has several layers to it (see link, below), and the layer that has the blood vessels capable of bleeding in it is further down than a superficial scrape would affect.
</span>
They breathe through their skin. Air dissolves on the mucus of their skin, so they MUST stay moist to breathe. If worms dry out, they suffocate. As fresh air is taken in through the skin, oxygen is drawn into the worm's circulatory system, and the worm's hearts pump the oxygenated blood to the head area.
Answer:
The activity of speed up the process.
Explanation:
Reverse transcriptase is an enzyme encoded from the genetic material of retroviruses that accelerate or speed up the process of transcription of retrovirus ribonucleic acid into deoxyribonucleic acid. Reverse transcriptase enzyme is also called RNA-directed DNA polymerase. Some retroviruses such as human immunodeficiency virus (HIV) and avian myeloblastosis virus used this Reverse transcriptase enzyme.