Genetic variation is essential for natural selection because natural selection can only increase or decrease frequency of alleles that already exist in the population. Genetic variation is caused by: mutation. random mating between organisms.
Answer:
ok well what do you need help with.
Answer:
-elastic membranes
Explanation:
The elastic membrane or tissue of the arteries allows the artery to bend and fit. It is important for artery to be elastic, because it transports oxygenated blood pumped from the heart to the tissues (except for pulmonary artery which carries deoxygenated blood) and thus have a blood pressure that is higher than in other parts of the circulatory system.
Add different kinds of soil to three potted plants
