Question

8/29 cfu - cells, cell membrane and transport (l)
what is true about the cell membrane? click all that apply.
□ it controls what enters and leaves the cell
□ it is made of a phospholipid bilayer
□ it contains all four biomolecules - proteins, lipids, carbohydrates and nucleic acids.
□ it is semipermeable
□ its primary function is to maintain homeostasis

Explanation:

1. The cell - membrane is a selective barrier that controls the movement of substances in and out of the cell, so "It controls what enters and leaves the cell" is true.
2. It is composed of a phospholipid bilayer, which is a fundamental structure of the cell - membrane, making "It is made of a phospholipid bilayer" true.
3. The cell - membrane mainly contains proteins, lipids, and carbohydrates, but not nucleic acids, so "It contains all four biomolecules - proteins, lipids, carbohydrates and nucleic acids" is false.
4. It is semi - permeable, allowing some substances to pass through while restricting others, so "It is semipermeable" is true.
5. One of its primary functions is to maintain homeostasis by regulating the internal environment of the cell, so "Its primary function is to maintain homeostasis" is true.

Answer:

It controls what enters and leaves the cell
It is made of a phospholipid bilayer
It is semipermeable
Its primary function is to maintain homeostasis