Question

In humans, dosage compensation
(a)Brings about equality in X- coded gene products
(b)Brings about equality in Y-coded gene products
(c)Brings about the determination of sex
(d)Is not involved in any of the above.

Answer 1

Hint: Due to the major difference in sex chromosomes, dosage compensation is a very important process for the balance of the genes in the body. Similar processes are seen in rodents and marsupials.

Complete answer:
In the case of humans, dosage compensation brings about equality in X-coded gene products. The process by which organisms equalize the expression of genes is called dosage compensation. Females(XX) silence the transcription of one X chromosome of each pair and transcribe all information from the other. This inactive one X- chromosome is called a Barr body.

Additional Information: Humans have 22 pairs of chromosomes called autosome, but there are two other chromosomes known as sex chromosomes which differ in males and females. They are designed as X and Y. Females have two Xs whereas males have one X and one Y. The X chromosome is medium-sized and contains 1000genes and Y is small and gene-poor. This imbalance in expression is lethal if not dealt with by dosage compensation. The difference is addressed by the silencing of genes one female X early in development. Both males and females then have only one active X chromosome which is compensated by twofold upregulation of genes on the active X.
This system continues to provide important insight into epigenetic regulation mechanisms.
So, the correct answer is 'Brings about equality in X-coded gene products'.

Note: Dosage compensation occurs to maintain the balance of genes in the body. As one of our sex chromosomes, the X has 100 genes whereas the Y chromosome is really small and doesn't contain that many genes. So the establishment of balance is very necessary. It is done by silencing one female X chromosome by dosage compensation.