Question

In a life cycle with alternation of generations, multicellular haploid forms alternate with

(A) unicellular haploid forms

(B) unicellular diploid forms

(C) multicellular haploid forms

(D) multicellular diploid forms.

Short answer

1. The option “unicellular haploid forms” isfalse.

2. The option “unicellular diploid forms” isfalse.

3. The option “multicellular haploid forms” is false.

4. The option “multicellular diploid forms” is true.

Step-by-step solution

Alternation of generations

Alternation of generations is a form of the life cycle that is exhibited by some organisms. In this type of life cycle, sexual reproduction and asexual reproduction take place alternatively. These two phrases are often very different from each other.

Explanation of option ‘(A)’

Some organisms exhibit alternation of generation. The multicellular haploid organisms do not alternate with unicellular haploid organisms. If an organism is haploid, its alternative life cycle will be diploid.

Thus, multicellular haploid forms do not alternate with unicellular haploid forms.

Therefore, the given option is false.

Explanation of option ‘(B)’

Alternation of generation occurs within a single organism, and hence they cannot change the number of cells within them during this process. If an organism is multicellular, its alternative life cycle will also be multicellular.

Thus, multicellular haploid forms do not alternate with unicellular diploid forms.

Therefore, the given option is false.

Explanation of option ‘(C)’

In some organisms that exhibit alternation of generation, they often show two phases. One phase is called the haploid phase, and the other phase is the diploid phase. In the haploid phase, only a single chromosome set is found, and others have two sets of chromosomes.

Thus, multicellular haploid forms do not alternate with multicellular haploid forms.

Therefore, the given option is false.

Explanation of option ‘(D)’

Alternation of generation exhibits two phases, of which one is haploid, and the other is diploid. The organisms that exhibit alternation of generations usually have the same number of cells, and their number does not change at any cost.

Thus, multicellular haploid forms alternate with multicellular diploid forms.

Therefore, the given option is true.