<h2>CNS </h2>
Explanation:
An example of a myelin producing cell in the CNS is oligodendrocyte
- The major function of oligodendrocytes is the formation of myelin
- Myelin acts as an insulator of axonal segments and is a prerequisite for the high velocity of nerve conduction
- Larger axons form thicker myelin
- During development, oligodendrocytes arise from precursors located in the sub-ventricular zone such as the sub-ventricular zone of the lateral ventricles for the cerebrum or the fourth ventricle for the cerebellum
- In the spinal cord, oligodendrocytes originate from the ventral regions of the neural tube and in the optic nerve they migrate into the nerve from the third ventricle
- It is the oligodendrocyte precursor cells which migrate to their destination where they then differentiate into the more mature oligodendrocytes
- The proliferation of the oligodendrocyte progenitor cells is controlled by a number of growth factors released predominantly from neurons but also from astrocytes such as platelet derived growth factor (PDGF) or fibroblast growth factor (FGF)
Viruses aren't made up of living cells, like plants and animals are, they either consist of DNA or RNA surrounded by coating of protein. Versus also like the properties of living things. They have no energy, they do not produce waste, and they do not respond to stimuli. they do not reproduce independently but must rely on invading living cells and feeding off a them.
Therefore, there are many reasons my viruses are considered non living but the biggest reason is because they cannot survive on their on and have to feed and get their nutrients off of living things
And bacteria is considered living because it can do all these things that viruses cannot do.
Answer:
tRNA and mRNA can leave the nucleus.
Explanation:
tRNA, when mature and correct, can leave the nucleus and enter the cytoplasm. mRNA can leave the nucleus through pores in the nuclear membrane. However, DNA cannot leave the nucleus, it has to be transcribed into RNA.