Video Transcript
True or False: Cross-pollination
can occur between two different plant species that share the same pollinator.
This question asks us about
pollination between two different plant species. You may recall that sexual
reproduction in flowering plants involves pollination and then fertilization of the
male and female gametes or sex cells. Pollen are microscopic grains that
contain the male gametes of a flowering plant. Pollen is produced in parts of the
flower called anthers. The female gametes, on the other
hand, are contained within a part of the flower called the ovary.
For a male gamete to fertilize the
female gamete, first, pollination must occur. This involves pollen being
transferred from the anther where it is made to a female part of the flower called
the stigma. The stigma is located above the
ovary, which houses the female gametes.
Cross-pollination specifically
occurs when pollen grains are transferred to the stigma of a flower on a different
plant of the same species. Animal pollinators like insects,
birds, and even mammals can be really helpful to transfer the pollen grains long
distances to a different plant. When pollinators like bees visit
flowers, some pollen rubs off onto the pollinator’s body. Then, if this pollinator visits a
flower on a different plant of the same species, the pollen may rub off the
pollinator’s body and onto this second flower’s stigma. This second plant has been
cross-pollinated.
Often, one type of pollinator might
visit and therefore pollinate many different species of flowering plants. However, successful
cross-pollination will only occur when the pollinator transfers pollen from one
flower to another flower of the same plant species.
We are asked to determine if
cross-pollination can occur between two different plant species that share the same
pollinator. Now we know that this statement is
false.
