Drought is an environmental condition characterized by scarcity of water. Less rainfall and reduced ground water levels facilitate drought like conditions. In the event of drought, animals face difficulty in finding food and water and thus are forced to migrate to other areas. However, flood is exact opposite to drought. It is caused by excess rainfall or increase in water level which destroys the ecosystem. It is not a characteristic of drought.
Scientists often study fruit flies because they have large chromosomes whose genes are easy to see. Every body cell of a fruit fly has 8 chromosomes. Every fruit fly gamete (sperm or egg) has 4 chromosomes.
