Question 17 from UPSC CSE 2020 - GENERAL SCIENCE

Question

Which of the following statements are correct regarding the general difference between plant and animal cells?
1. Plant cells have cellulose cell walls whilst animal cells do not.
2. Plant cells do not have plasma membrane unlike animal cells which do.
3. Mature plant cell has one large vacuole whilst animal cell has many small vacuoles.
Select the correct answer using the code given below:

Accepted Answer

Correct Option: C. 1 and 3 only

Strategy: - Identify direct characteristic differences between plant and animal cells.
- Confirm statement 1 based on the presence of a cell wall in plant cells, which is absent in animal cells.
- Eliminate statement 2, as both cell types possess a plasma membrane; in plants, it lies within the cell wall.
- Confirm statement 3, noting plant cells typically have a large central vacuole while animal cells have several smaller ones.

Key Info: Plant cells are distinguished by a rigid **cell wall**, primarily composed of cellulose, which provides structural support and protection. This critical feature is absent in animal cells.

Both plant and animal cells possess a **plasma membrane** (also known as the cell membrane), a semi-permeable layer regulating molecular transport. In plant cells, this membrane is situated just inside the cell wall.

Regarding **vacuoles**, mature plant cells typically contain a single large central vacuole vital for maintaining turgor pressure, storing nutrients, and managing waste. Conversely, animal cells usually have multiple, smaller vacuoles primarily used for storage and transport.

Other key distinctions include the presence of **chloroplasts** for photosynthesis in plant cells (absent in animal cells), and **centrioles** which are common in animal cells but not plant cells.

Answer

Option A: 1 and 2 only

Answer

Option B: 2 and 3 only

Answer

Option D: 1, 2, and 3