Bean beetles, sordaria, Marz Meloos, and Tribbles! Exciting things are happening in the Genetics class this year.
The first day we planted corn, which we will observe in order to determine the dominant and recessive traits of corn in a tall/dwarf cross, a green/albino cross, and a dyhybrid tall/dwarf/green/albino cross. Every day we will observe our corn, and during the third week, we will compare the observations of each group in order to determine the dominant or recessive nature of the traits.
The second day, we began our work with bean beetles. They are tiny beetles the make their home in mung beans. Each group has chosen a different variable to study in respect to its beetles, so we have dishes of beetles all over the room. Some are studying the amount of eggs that are laid when deceased females and males are left in the dish and some are replacing the dead with fresh beetles every day. Others are studying which type of bean the beetles prefer between mung beans, pinto beans, and kidney beans.
We also began an experiment involving the ability of the mung beans to grow when they are used by the beetles. Mature beetles lay their eggs on a bean, and when the eggs hatch, the baby beetles chew their way out of the bean. Students are testing whether beans with eggs on them and beans that have beetles hatch out of them grow as well as those that have not been disturbed by the beetles.
The final experiment we began on Tuesday was our sordaria experiment. In this experiment, we have placed brown and tan sordaria in a petrie dish to grow together. As they intermingle, their genes will be exchanged and will cross over during meiosis, so their offspring will contain both brown and tan spores.
We also did two simulations on Tuesday that involved breeding Mars Meloos and Tribbles. During the Tribble simulation we learned about and discussed simple dominant and recessive traits. The Mars Meloos simulation was a demonstration of incomplete dominance.
Today, we will be observing the experiments already in progress, studying the affect of multiple alleles with a rexies simulation, and beginning dihybrid crosses.