A. external
These types of signals are observed when there is a cut on the body. The epidermal cells lose contact with one another and divide faster until they are in contact once again. After they come into contact, division slows down again.
Trophic level: the feeding level of an organism in a food web or chain. Food web: a diagram showing a series of interconnected food chains and the flow of energy through an ecosystem. Food chain: a diagram showing the flow of energy from one trophic level to the next. E.g. Consumer or decomposed Consumer: an organism which feeds on other organisms to obtain its nutritional requirements (part of a food web/chain). Producer: an organism capable of trapping the suns energy and converting it to sugar in the process of photosynthesis. Therefore the term food web is the term used to include all of the above.
hope this helps, :)
Answer:
To release the nutrients inside of it
Explanation:
Plasma Membrane is the answer