Genetic variation<span> occurs </span>mainly<span> through DNA mutation, gene flow (movement of genes from one population to another) and sexual reproduction</span>
Carpool to work,ride the bus,or switch to electric cars.
Answer:
Amber is the fossilized resin from ancient forests. Amber is not produced from tree sap, but rather from plant resin. This aromatic resin can drip from and ooze down trees, as well as fill internal fissures, trapping debris such as seeds, leaves, feathers and insects.
There are many environmental negative direct outcomes of unused excess nitrogen from nitrogenous fertilizers. One of these is eutrophication. Eutrophication is the excessive richness of nutrients in a water body as a result of fertilizer run offs from the land, which causes a dense growth of plants in the water. Other negative outcomes are: green house effects, acid rain and contamination of underground water which has negative effects on human health.
