Answer:
One
Explanation:
In a controlled experiment only one variable is changed at a time, while the others are kept the same/controlled so changes can be observed and a causation can be determined.
Answer: they absorb photons from sunlight.
Explanation:
The cytoskeleton of a cell allows the cell to be flexible. Our human skeletons allow <em>us </em>to be flexible.
Ozone, which is also known as trioxygen, is a chemically bonded compound, and contains three oxygens.
Answer:
a. allow a variety of molecules to cross the cytoplasmic membrane
Explanation:
The cells have different molecules in its membrane. As a membrane the main function of it is to regulate the income and outcome of substances that the cell needs or the cell has like some wastes.
Some of these molecules can be some proteins like the permeases, that is going to regulate the solutes that can enter the cell, but since they are non specific, that means that can not make the difference among one carbohydrate and another (as an example).
