Our elbow bends all the time, we bend it when we pick up things, when we eat, when we do mostly everything. Cows on the other hand dont pick up food with there feet, they use there mouths, and they probably only bend when they are walking.
I believe the correct answer would be <span>variation. The definition of variation in biology means,</span><span> any difference
between cells, individual organisms, or groups of organisms of any
species caused either by genetic differences or by the effect of environmental factors on the expression of the genetic potentials. So i think that organisms can also be classified as variation. Hope this helped. ♥ ☺
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Explanation:
1). Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure.
Chromosomes are not visible in the cell’s nucleus—not even under a microscope—when the cell is not dividing.
2) is pic
It's the concentration of sense organs, nervous control, etc., at the anterior end of the body, forming a head and brain, both during evolution and in the course of an embryo's development.
