Biosynthesis of many molecules in cells, and many modifications of macromolecules like proteins, RNA, and DNA require addition o
f single carbons. What is/are the major carrier/s of single carbons in cells? a) S-adenosylmethionine
b) Acetyl CoA
c) Tetrahydrofolate
d) a and b
e) a and c
Single carbons are atoms needed for the biosynthesis of many molecules in cells, therefore the cells need a pathway to move group of atoms containing single carbons to make them available for the biosynthesis. S-adenosylmethionine and Tetrahydrofolate are two of the major carriers of single carbons in cells. S-adenosylmethionine (SAM) acts as a methyl (-CH3) donor and Tetrahydrofolate (THF) as a cofactor in enzymatic reactions.
Crossing over – often, the sister homologous chromosomes of a cell exchange genetic material through recombination of genes.
Independent assortment/random fertilization – there are numerous variety of ways that the chromosomes of the gametes can combine, after meiosis, through fertilization to form a zygote
Mutation – on rare occasion, there is a slight and random change in the genes of a gametic cell caused by environmental factors.
