Reproduction
St. John's wort is a perennial plant that has asexual and
sexual reproductive capabilities. Perennial means that it can
live for more than two years. These plants are also cyclic
meaning it has large population swings year to year.
The most common way of reproducing in angiosperms is through
sexual reproduction. In this process, the flower of a mature adult
will have an ovary and an anther. Meiosis will take place producing
haploid cells. The haploid cells will go through mitosis to create a
pollen sac and an embryonic sac. Pollination and fertilization will
begin when sperm travels through the pollen
tube. Seeds are produced
and kept in the fruit. These seeds can be transported via wind.
Often the seeds are eaten by animals. They are carried in the
animal's digestive tract and found in dung.
The other form of reproduction is through asexual reproduction. In this form plants create runners and rhizomes. Runners, otherwise known as stolons, are above ground shoots that are created by the parent plant. They produce tiny root and shoot systems along their length. As they grow immature roots will develop and anchor the plant. The shoots will grow and spread rapidly. The shoots grow into replicas of the parent plant. Rhizomes are horizontal tunnels beneath the surface of the soil. These produce new shoots that have the capability to develop new offspring and produce their own rhizomes. Some advantages to asexual reproduction are the chances of reproduction will increase and plants can reproduce in undesirable conditions. The main disadvantage is that the offspring is a clone of the parent so any undesirable characteristic the parent has the offspring will have as well.
