Question

The diagram below represents the general appearance of a section of the cell membrane under an electron microscope.

1. State the possible composition of layers A and B. 
2. What is the significance the structure A in the membrane? 
3. State two properties of the cell membrane that make it efficient in its functions. 
4. Give two reasons why an electron microscope is useful in the study of the cell structure. 

Answer 1

1. A – proteins
   B – Lipids / Phospholipids
2.  
   1. Protein is sensitive to changes in temperature / pH; which makes it efficient in allowing substances to move across cell membrane.
   2. Proteins give the membrane structural support.
3.  
   1. Semipermiability, it selects what enters and what leaves the cell.
   2. It has electric charges so that it can detect changes in the environment.
4. The electron microscope has a high resolution and high magnifying power thus give fine details of the cell.