Question

Describe autogamy and allogamy.

Answer 1

Autogamy, or self-fertilization, refers to the fusion of two gametes that come from one individual. Autogamy is predominantly observed in the form of self-pollination, a reproductive mechanism employed by many flowering plants. However, species of protistshave also been observed using autogamy as a means of reproduction. Flowering plants engage in autogamy regularly, while the protists that engage in autogamy only do so in stressful environments.

Allogamy" (cross-fertilization) is a term used in the field of biological reproductiondescribing the fertilization of an ovum from one individual with the spermatozoa of another. By contrast, autogamy is the term used for self-fertilization. In humans, the fertilization event is an instance of allogamy. Self-fertilization occurs in hermaphroditicorganisms where the two gametes fused in fertilization come from the same individual. This is common in plants (see Sexual reproduction in plants) and certain protozoans.

Answer 2

Dear Student,

● Autogamy -

• Type of pollination in which pollen grain of a flower falls on stigma of same flower is called autogamy.

● Allogamy -

• Type of pollination in which pollen grain of a flower falls on stigma of a flower of another plant of same species is called allogamy.

◆ Difference between autogamy and allogamy -

• Autogamy is type of self pollination and allogamy is type of cross pollination.
• In autogamy, egg cell fuses with sperm cell of same plant while in allogamy egg cell fuses with stem cell of different plant.
• Autogamy is of only one type but allogamy is further classified as xenogamy & geitonogamy.
• Allogamy is important for evolution, autogamy isn't.

Thanks dear. Hope this helps you...