Chapter 29, Problem 1TY

Summary Introduction

Introduction: Microscopic, branched filaments known as hyphae form a distinctive body of fungi known as mycelium. “Fungi are heterotrophic in nature”, and they can grow in soil, a piece of bread and several other materials.

Answer to Problem 1TY

Correct answer: Both fungal and animal cells are eukaryotic in nature. However, the absence of cell walls in the animal cells distinguish them from the fungal cells. Hence, the correct answer is option c.

Explanation of Solution

Reason for correct answer:

Fungal cells have a rigid layer external to the plasma membrane called cell wall. The cell wall of fungi is made up of chitin and they play role in the protection of cells. This protective layer is absent in animal cells.

Option c. is given as “have chitin-rich cell walls, whereas animal cells lack cell walls”.

The presence of chitin-rich cell walls in the fungal cells differentiates them from the animal cells. Hence, the correct answer is option c.

Reasons for incorrect answer:

Option a. is given as, “lack ribosomes, though these are present in animal cells”.

The cells of fungi are eukaryotic in nature. Therefore, like animal cells, fungi also contain ribosome, a cell organelle. Hence, option a. is incorrect.

Option b. is given as, “lack mitochondria, though these occur in animal cells”.

Cell organelles such as mitochondria are required to provide energy to the cell in the form of ATP molecules and are present in all eukaryotic cells including the animal cells and fungal cells. Hence, option b. is incorrect.

Option d. is given as, “lack cell walls, whereas animal cells possess cell walls”.

Fungal cells have a protective layer in the form of a cell wall, which is mainly composed of chitin. However, animal cells do not have cell walls. The organelles present in the animal cells are enclosed within a phospholipid bilayer known as the plasma membrane. Hence, option d. is incorrect.

Option e. is given as, “none of the above is true”.

Fungal cells possess cell walls made up of chitin and it is absent in the animal cells. This makes option c. correct. Hence, option e. is incorrect.

Hence, the options a., b., d., and e. are incorrect.

Conclusion

Thus, cell walls mainly composed of chitin is present in fungal cells, but it is absent in the animal cells.