What is cross fertilization?

Answer 1

Cross Fertilization refers to the crossing of species... for example, if you take "male" gametes from a green pea plant and mix them with "female" gametes of a yellow pea plant, you will find the progeny is a mixture of both species... you get green and yellow peas.

Answer 2

using two different sources of gametes (sperm-egg), one different male organism, one different female organism, so that the genes for fertiliztion do not come from the same organism in self fertilization (where there is less gentic variation)

In plants we call these mechnisms cross pollination or self pollination. The design of the flower and the positon of the male-female parts of the flower (anthers-pollen in relation to the stigma syle female) can determine which occures: self or cross fertilization. If anther males that produce pollen are above the female style and stigma, then flower uses self pollination, if anthers are below stigma, cross pollination, but flowering plants also rely on birds-bees (pollinators) to assist pollen distribution; so most plants use cross pollination even with the help of the pollinators.

Pine trees use cross pollination too. Position of the male pine cones are lower on pine tree branches than the female cones which are up on higher branches. Swirling mountain wind currents blow the pollen all over the forest so that there is opportunity for pollen to mix up and allow genetic variation of pollen from a tree a couple hills-miles away pollinating female cones further away during mtn breezes.

Answer 3

Cross fertilization relates to the interbreeding of two distinctly known species or subspecies as an attempt to create a new organism.

There are mechanisms (both prezygotic and postzygotic) that are in place to prevent most forms of cross breeding, but there are still cases where it does occur.

Answer 4

Heterosis is increased strength of different characteristics in hybrids; the possibility to obtain a "better" individual by combining the virtues of its parents.

This is commonly known as hybrid vigor or outbreeding enhancement. It is often the opposite process of inbreeding depression, which increases homozygosity. Heterosis is an example of heterozygous advantage. The term often causes controversy, particularly in terms of domestic animals, because it is sometimes believed that all crossbred plants or animals are better than their parents; this is untrue. Rather, when a hybrid is seen to be superior to its parents, this is known as hybrid vigor. It may also happen that a hybrid inherits such different traits from their parents that make them unfit for survival. This is known as outbreeding depression, typical examples of which are crosses between wild and hatchery fish that have incompatible adaptations.