<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)
I believe the correct response is the third option. Have higher resolution that allows you to view smaller specimens.
DNA mutations that actually originate in the gametes is mainly responsible for genetic biodiversity existing in modern organisms. The term biodiversity actually refers to the variety as well as variability of life that is found on the planet earth. his variety can be seen between species, the ecosystem and within the species.<span />
Answer:
b. Frank received the mutant chromosome from his father. Nondisjunction occurred in his father during the first meiotic division.
Explanation:
As you can see in the question above, Frank has Klinefelter syndrome which causes him to have normal skin patches and skin patches without sweat glands. Her mother has completely normal hair, which may indicate that the defective gene was not supplied by her. In addition, Frank's father has anhydrotic ectodermal dysplasia, an X-linked condition where the skin does not contain sweat glands.
Although Frank's father's defective gene is linked to the X chromosome, it is likely that Frank inherited the defective gene from his country. This may have occurred because during meiosis I, his father's genes did not show disjunction. As a result, Frank presents a mosaic of his phenotype, because an inactivation of the X chromosome occurred.
