Life History Of Drosophila

Development and maturation There are three distinct morphological stages during development of Drosophila: egg, larva, and pupa. Approximate durations of each stage (at 25°C) are shown in Table 22.1. At 25°C, it takes around 10 days for a fertilized egg to become adult. Eggs are laid on the surface of the food medium. The egg is very small, shiny white, and ovoid (about 0.5 mm). The larva is a worm-like creature that feeds extensively. The larva molts twice, and the periods between the molts are called instars; thus the larva undergoes three stages as the first, second and third instars. It rapidly expands during molting before the new cuticle hardens (2-3 mm long at the third instar). The third instar larva eventually stops feeding and crawls out of the food medium and becomes still. After several hours a white prepupa (about 2 mm) is formed. It becomes brown within an hour, and air bubbles come out from the abdomen making it buoyant. Most pupae are stuck to the wall of the container or on the stopper. During pupation, imaginal discs develop in the tissues of the adult fly (about 3 mm).

Flies tend to eclose just before dawn. Newly eclosed adult flies have a soft cuticle and folded wings. It takes several hours for the wings to become unfolded, dry out and harden. Very young flies are light colored and have dark meconium in the gut, visible through the ventral abdominal wall. Flies do not mate for 8 hours after eclosion; this is a critical period in which virgin females can be collected. The lifespan of adult flies is dependent

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Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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