2022 · Q16
Which one of the following statements is correct about the cell membrane?
General KnowledgeBiology
- AIt is made up of cellulose.
- BIt is a permeable structure for all substances.
- CIt is flexible and enables the cell to engulf many materials.
- DIt does not allow diffusion of gases liek oxygen and carbon dioxide.
Explanation
The cell membrane is a flexible phospholipid bilayer — it is not made of cellulose (that is the plant cell wall). It is selectively permeable, not open to all substances, and it freely allows diffusion of small gases like oxygen and carbon dioxide. Its flexibility lets cells engulf particles by endocytosis (as in Amoeba and white blood cells).