Answer: Glial cells called ASTROCYTES help maintain the blood-brain barrier, whereas SCHWANN CELLS create the myelin that envelopes axons
Explanation: Glial cells are specialized cell that are found in both central and peripheral nervous systems, that surrounds the neurones, providing them with support and insulation. There are different types of Glial cells these includes:
- Astrocytes: they maintain the blood brain barrier.
- Schwann cells: create the myelin that envelopes axons of the peripheral nervous system neurones.
- satellite cells: These cells help regulate the external chemical environment of neurones.
- Microglia: they clean up cellular debris through phagocytosis.
- Oligodendrocytes: create the myelin that envelopes axons of the central nervous system
tundra and tropical rain forest
C. natural selection.
This is because in smaller populations the more that two separate groups of animals don’t interbreeding the father they become until speciation occurs where they cannot interbreed between the two groups.
Answer:
Explanation:
It's a normal part of nature, and one of many ecological factors that help keep the hundreds of thousands of living plants. It also keeps animals in balance with one another.
