Guide to the practical teaching
of biology and genetics

Model organism

TASK 1: Genetic experiment

Genetic experiment - crossing of red-eyed drosophila (original wild form) with mutant wite-eyed drosophila. Experiment will proceed during three lessons:

The beginning of experiment (1^st lesson)
You will be divided into groups. Each group will receive an Erlenmeyer flask with a fresh medium (maze grit, dry yeast, sugar and agar) and two tubes with drosophila of different sexes (male, female) and different eye color (red, white). Observe them and then carefully place females and males with different eye colors together into the Erlenmeyer flask. Mark the flask with the date, sex and eye colors of crossed drosophila and identification of your group.

Removing of adult drosophila (2^nd lesson)
Drop ether on the cotton placed at the cover of the bottle and close it. Wait a few minutes and subsequently remove the adult fruit flies from the Erlenmeyer flask into the bottle with ether to narcotize them.

Evaluation of experiment (3^rd lesson)
Use ether to narcotize fruit flies (offspring of crossing) and sort them according to sex and eye color; deduce how the observed trait (eye color) is inherited.

TASK 2: Mutant strains

Observe different mutant strains of drosophila (white, yellow, ebony, curly and vestigial) - live, in alcohol or on the picture.