cell membrane

The cell membrane it holds and protects the cells. The cell membrane also is an control substances that come into and out of the cells. The cell membranes nickname is "Gate of the cell". It has that nickname because it is protecting the inside and outside of the cells just like a gate lets certain things in a building and certain things out.

what are cells?

There are 3 different cells and they are for plants, animals, and humans. Cells are like legos blocks because they are basic units of all living things. You can't look at cells with your eyes you have to look through a microscope. All cells are not the same they have there own structure. We never run out of cells because we get new ones from the existing cells. When we grow because our cells are making more and more and more cells.

Body Systems Keep us Alive

• The digestive system helps keep us alive because it helps break down the foods and drinks and get all the molecules of nutrients before they can be absorbed into the blood and carried to cells throughout the body.
• The urinary system helps keep us alive because it helps with the lungs, skin, and intestines-all of which also excrete wastes-to keep the chemicals and water in your body balanced.
• The respiratory system is important because it takes in carbon dioxide and produce oxygen, which keeps us alive. The respiratory system gets oxygen from the air so that cells can change food into energy. We need energy for our bodies and then we can stay active.