The Plant Kingdom Asexual Reproduction

All plants can reproduce sexually Many plants can also reproduce asexually

Sexual Reproduction Remember several things happen during the process of meiosis and sexual reproduction that create genetic variation in offspring. Crossing over and independent orientation Random fertilization

Asexual Reproduction Does not involve gametes Gametes are produced through the process of meiosis Only the process of mitosis is involved Mitosis produces genetically identical cells, so the offspring is identical to the parent.

Asexual Reproduction Sometimes a portion of a plant forms the structures to make another complete plant Sometimes the parent plant forms small complete plants called plantlets on special stems or leaves that can grow independently

Shoots from spreading roots A cattail started from a seed can produce almost 100 shoots from spreading rhizomes in a single year. Rhizome- thick, fleshy, horizontal underground stems that produce leaves or leaf-bearing branches Plants like iris, bamboo, lilac, elderberry, grass, and many herbaceous weeds reproduce by rhizomes or shoots produced from spreading roots.

Bulbs Bulb- collections of storage leaves that branch from small discs of underground stems Once a bulb matures, tiny bulblets develop from lateral buds at the base of the parent plant. Tulips, hyacinths, and daffodils, onion

Tubers Tubers are underground stems that often produce abundant lateral buds, each of which may develop into a new plant. The white or irish potato is a familiar example

Stolons Stolons are stems that produce plantlets at their nodes. The plantlets grow heavy enough to bend the plant to the ground and root themselves Adventitious roots- grow from a stem, a petiole, or a leaf Strawberry plants, spider plants, eelgrass, and bermuda grass http://theseedsite.co.uk/ http://theseedsite.co.uk/bulbs.html

Tissue Culturing Plant cells are like embryonic stem cells Most plant cells have the ability to differentiate into all other types of plant cells. The term describing these types of cells is totipotent. Scientists can take a single cell with the desired genetic makeup and culture entire plants from that This is called tissue culturing

Pros of Asexual Reproduction Asexual reproduction can be induced by humans. Can reproduce clones that have beneficial characteristics Usually quicker than planting a seed

Cons of Asexual Reproduction Genetic variation is essential for the survival of a species You might want to reproduce genetically identical plants because they have certain qualities that are beneficial, but by doing this you make the population susceptible to being wiped out.