Answer: Myelin Sheath. The Myelin Sheath of a neuron consists of fat-containing cells that insulate the axon from electrical activity. This insulation acts to increase the rate of transmission of signals. A gap exists between each myelin sheath cell along the axon.
Explanation:. Myelin can greatly increase the speed of electrical impulses in neurons because it insulates the axon and assembles voltage-gated sodium channel clusters at discrete nodes along its length. Myelin damage causes several neurological diseases, such as multiple sclerosis.
Ok this is going to make me work sadly with a time restraints that I have I will be unable to draws the first picture however the rest I can do. 2. vestigial structures are generally parts of an animal's body that is unnecessary and no longer used. specifically whales have vestigial pelvis bones and as you know they dont walk as for my body the appendix is also a good example it kinda just sits there waiting to become infected. 3. embryos from separate organisms in very early stages look VERY alike and can be incredibly difficult to tell them apart from one another. 4. Everyone's favorite dioxy ribonucleic acid or DNA can show ancestry they do this by being similar like my DNA isnt exactly the same as my mothers however there are more then enough similarities in our DNA to tell that we are related. This works for any and all animals as long as they have salvageable DNA so dinosaurs dont count. using DNA we can also tell that I'm more closely related to a dolphin than a shark and I'm more closely related to sharks than sponges. hope I answered what you were looking for thoroughly
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hope the answer helps this is what I understand