B. because they are not manufactured by the body
Answer: a) relies on the uptake of an external signal molecule from the cell
Explanation: Signal transduction is known as the transmitting of any signal of a molecule from exterior of cell to interior of cell.This technique is termed as critical is taken care of successful transmission of signal effectively and positive result and reception is done by the cell surface receptors.It is also known as cell signalling. Thus,option(a) is the correct option of all.
Answer
The main reason being the amount of food available.
Explanation:
Think of it this way:
If an animal is trying to find food but another species is looking for the same prey then its going to be increasingly difficult for the species to find prey and if there's not enough of the prey species then the population of the predator to go down.
That is why its considered a limiting factor.
If it doesnt have a nucleus or a cell wall it is a prokaryote. also prokaryotes displayed in pictures tends to be longer