Plant ReproductionVocabulary & Images

1.Frond-fern leaf

2.Rhizome- underground stem

3.Sori- structures in which fern spores are produced; usually found on underside of fronds(Plural is sorus)

4.Prothallus- small, green heart shaped plant that grows from a fern spore

This photo shows a prothallus that grew from a single fern spore. It is tiny and fragile, only about 1-3 millimeters across. It is visible with the naked eye, but a microscope is required to see the sex organs on its surface.

The dark area in the center is where tiny sex organs grow, male structures that produce sperm and female structures that produce egg cells.

When the prothallus is flooded with water, sperm swim to eggs and fertilization occurs. (Usually male and female parts don't mature at the same time on one prothallus, so the sperm must swim to another one nearby.)

This photo shows a fern embryo growing from a prothallus. 

B is the structure shown in the photo above, now dying, it's function accomplished.

A is the fern embryo, which is growing from a fertilized egg.  The embryo extends from the leaf (marked A) all the way down to the dark root going off to the left at the bottom of the photo.

This embryo will grow into the large fern plant, like those shown in the photos on the next slide.

5. Pollen Grain- part of the plant’s male reproductive organ that contains sperm.

6. Pollination- transfer of pollen grain from the male to female reproductive organs of plants

Self Pollination