Limiting factors are resources or other factors in the environment that can lower the population growth rate. Limiting factors include a low food supply and lack of space. Limiting factors can lower birth rates, increase death rates, or lead to emigration.
It can be a heat insulator, which means it can trap heat in and reduce heat loss to keep us warm. it can also protect organs, it can act as a shock absorber
They're both types of active transport that are the intake of something into a cell. Khan Academy has a great article on this. I recommend checking that out.
