The starch and glycogen are two most suitable storage polysaccharides because

Options

A. they occupy less space
B. they do not disturb ph of cell
C. they cannot pass through cell
D. all of the above

Answer

### Step-by-Step Solution:

1. **Definition of Starch and Glycogen**:
- Starch and glycogen are both polysaccharides that serve as storage forms of energy in living organisms. Starch is primarily found in plants, while glycogen is found in animals.

2. **Structure**:
- Both starch and glycogen are long-branched polymers made up of glucose units. This branching allows them to be compact and efficient for storage.

3. **Storage in Organisms**:
- Starch is the main storage polysaccharide in plants, found in structures such as tubers, rhizomes, and seeds.
- Glycogen serves a similar function in animals, being stored mainly in the liver and muscle tissues.

4. **Energy Release**:
- When energy is needed, glycogen can be broken down into glucose, which helps maintain blood glucose levels. Starch can also be broken down into glucose when needed by plants.

5. **Advantages of Starch and Glycogen as Storage Polysaccharides**:
- **Space Efficiency**: Both starch and glycogen can store a large amount of energy in a compact form due to their branched structure, allowing them to occupy less space within cells.
- **pH Stability**: They do not disturb the pH of the cell, which is crucial for maintaining cellular functions.
- **Cell Membrane Permeability**: Their large size prevents them from passing through cell membranes, ensuring that they remain within the cells for storage until needed.

6. **Conclusion**:
- Therefore, starch and glycogen are considered the most suitable storage polysaccharides because they occupy less space, do not disturb the pH of the cell, and cannot pass through the cell membrane. Thus, the correct answer is "all of the above".