6.

Evolution explains how variations can lead to changes in a species

Evolution is the process by which populations of organisms change over generations. Genetic variations underlie these changes. as we evolve our genetic genes change because the gametes come from 2 parents and has half the DNA (23)  and thousands of years passes and if you will compare people in ancient times to now we are completely different.

vascular tissue transports materials from the environment into the plant.

the answer is a) cell division.

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