Answer:
Men express all the X-linked genes present in their genome.
Explanation:
Human males have one copy of X and one copy of Y chromosomes. They express all the alleles present on their X chromosome irrespective of its dominant or recessive nature. This occurs because males do not have a second copy of the X chromosome to carry another allele for the same gene. Color blindness is caused by a recessive allele present on the X chromosome. Males carrying one copy of this allele exhibit the disease while females need two copies of the allele of color blindness to express the disease. Therefore, males are more frequently affected by this disease.
Answer:
A callus is a hardening of skin, keratin is the protein which is abundant in callus. Skin is a protective layer against a external environment. Outer layer of skin consist of keratin which is also found in hair. Callus is the accumulation of dead cells result due to friction and pressure exerts on the part in which they are present. The keratin component (keratinocytes) remains undifferentiated in these dead cells which causes hardening in callus.
I know why farmers use fertilizers..... to provide nutrition for the plant