Why are women often carriers of X linked traits but rarely affected by them?

X-linked inheritance means that the gene causing the trait or the disorder is located on the X chromosome. Women have two X chromosomes; men have one X and one Y. Genes on the X chromosome can be recessive or dominant. Their expression in females and males is not the same.

Women have 2 X chromosomes, unlike men who have XY. In women, a recessive allele on one X chromosome is often masked in their phenotype by a dominant normal allele on the other.

Explanation:

In informal words, if you have an X-linked trait that is recessive and are male, you will be affected cuz there is no other X to "override" that recessive trait because Y is (as we know) non-coding. Whereas if you are female, both of your Xs would have to carry a recessive trait for you to be affected, thus it is rarer for women to be affected by X-linked traits.

tsd is temerature dependent sex determination.

tsd: it is a type of environmental sex determination in which the temperature experienced during embryonic/ larval development (ambient temperature for development) determine the sex of the offspring.

crocodile displays the tsd where the ambient temperature of the developing egg determines the individual's sex. for example in the american alligator's eggs, incubation at 33 ºc produces mostly males, while incubation at 30 ºc produces mostly females. so if the american alligator's egg will get the ambient temperature (33 degree celcius)during embryonic development from egg, the offspring will be male and same for the female sex determination.

the cladogram shown here shows similarities and differences among several classes of vertebrates. anatomically, the four have limb structure as their common ancestor. we might separate the mammals from the other three classes because they a) divergent; do not lay eggs b) identical; are warm-blooded c) varied; a four chambered heart d) homologous; have mammary glands