Which tissues of the central nervous system contain myelin?
a. dura mater
b. arachnoid mater
c. grey matter
d. white matter

D. White matter

Explanation:

White matter is composed of nerve cells that are covered by myelin, a fatty substance with proteins that provides and insulation and protection, in the brain. This myelin contributes to the name and colour of whiter matter. White matter is found in the deeper parts of the brain, connecting nerve fibers and transmit messages faster due to myelin.

the correct answer is b

in the year 2850, humans successfully colonized mars. the martian modules that were constructed could hold only a small population of people. it is now a century later, and the population on mars has grown to 600 people. of the current mars population, 45 people express the recessive phenotype for phenylketon- uria (pku) syndrome (pp genotype).

explanation: