What lead to the variation within a species or a population plz answer this question

Because of its structure the cell membrane is known as a phospholipid ? a.bilayer b.molecule c.fluid d.barrier

Describe how an electric generator works

In a classic experiment using pea shape, mendel conducted two separate genetic crosses. in the first cross the parent plants were “true breeding” for pea shape; one had round peas ( r )and the other had wrinkled (r). the first cross produced a filial 1 generation of all round peas. in the second cross, mendel bred plants from the filial 1 generation. this cross produced different results. out of approximately 1000 plants, about 75% were round and 25% were wrinkled.