preview

Fruit Fly Lab Report

Decent Essays

Introduction Drosphila melanogaster, commonly known as the fruit fly, is an excellent organism for genetics studies because it has simple food requirements, occupies little space, is robust, completes its life cycle in about 12 days at room temperature, produces large numbers of offspring, can be immobilized readily for examination and sorting, and has many types of hereditary variations that can be observed with low-power magnification. The fruit fly has a small number of chromosomes (4 pairs), which are easily located in the large salivary gland cells. As mentioned before, the fruit fly life cycle is complete in about 12 days. First, a fertilized adult female must lay the egg, which leads to the first stage of the fruit fly life cycle, the egg stage. This first stage consists of a small, oval-shaped zygote with two filaments at one end. They are typically laid on surfaces of the vial and last for only about a day in optimal conditions. The egg, after a day, will then hatch into a larva, which marks the start of the larva stage. Lasting for about 3 days, the larva stage is broken up into three different segments: the first instar larva, second instar larva, and third instar larva. Throughout these stages, the wormlike larva eats continuously. A cream colored or white, wormlike organism with no legs or eyes except for hook-like mouthpiece for feeding. The larva feeds in the food medium for about 3-6 days then it leaves the food source in search of dry place to pupate. The first instar larva lasts for about a day or two, during which it mostly feeds the entire time, then the larva sheds its outer skin (cuticle) and enters the second instar stage, where it is bigger and more defined. From there, it repeats the same process as the first instar. …show more content…

The two most easily seen differences between male and female fruit flies are abdomen shape/size and sex

Get Access