Question

In Figure 29.12, if fertilization occurred between gametes from one gametophyte, how would this affect the production of genetic variation

from sexual reproduction?

Short answer

If fertilization occurs between gametes from the same gametophyte, the resulting offspring will be genetically identical. Thus, it results in the formation of clones. This is because all the cells produced by a gametophyte are descents of a single spore.

Step-by-step solution

Alteration of generation

The term alteration of generation indicates the life cycle of plants in which they form by two methods: gametophyte and sporophyte. Gametophyte generation indicates the generation in which plants produce gametes for their reproduction. In sporophyte generation, plants produce spores.

Genetic variation in sexual reproduction

In sexual reproduction, genetic variation (change in the genetic material of an organism) occurs due to three basic methods. These are an independent assortment of chromosomes, crossing over, and random fertilization.

If fertilization occurs between gametes of the same gametophyte, clones will be produced, and genetic variation will be reduced.

Effect of gametophyte on genetic variation from sexual reproduction

The egg and sperm cells produced by the same gametophyte are descendants of a single spore. Hence, they are genetically similar and give rise to similar offspring.

Although crossing over and independent assortment results in genetic variation during spores production, genetic variation slows down due to fertilization between gametes of the similar gametophyte.