The chromosomes are of two types i.e. autosomes and sex chromosomes. There are 22 pairs of autosomes and 1 pair of sex chromosome in a cell of a human. The sex chromosomes are those which participate in determining the sex. The two sex chromosomes are X and Y. A female human has two X chromosomes whereas the cell of a male human is composed of one X and one Y chromosome.
Hence, the ovum contains a pair of X chromosome whereas the chromosome in sperm maybe X or Y. In the case of mammals, these sex chromosomes determine the gender of the organisms.
Meiotic nondisjunction is much more likely than mitotic nondisjunction. Based on
A woman who is heterozygous, Bb, has brown eyes;
Explain why familial breast cancer shows a dominant pattern of inheritance in
How is an F′ factor different from an F factor?
With regard to the timing of conjugation, explain why the recipient
The raw material for evolution is random mutation. Discuss whether or
Why is an antibody used in this experiment? From
Explain the type of speciation (allopatric, parapatric, or sympatric
In fruit flies, curved wings are recessive to straight wings,
A recessive allele in mice results in an unusally long neck.