the inheritance of sex

Question 1

what is gender determined by?

Answer 1

gender is determined by the combination of chromosomes in a zygote, rather than the genes themselves

Question 2

what are the types of sex chromosomes?

Answer 2

the sex chromosomes are of 1 or 2 types, which may be large, X chromosomes or small, Y chromosomes

Question 3

what chromosomes do human females and human males have?

Answer 3

human females have 2 X chromosomes. their genotype is sometimes describes as 22XX, meaning 22 pairs of homologous chromosomes, plus 2X ones.

human males have an X and a Y chromosome and are described as 22XY.

Question 4

what does the ova of females and the sperm of males contain?

Answer 4

the ova of all females have 22 single chromosomes plus 1 X. the sperm will contain 22 single chromosomes and either an X or a Y chromosome. thus, it is the male gamete that determines the sex of the offspring.

Question 5

what are the probabilities of 2 parents producing a male or female child?

Answer 5

there is always a 50% probability of 2 parents producing a male child and the same probability of a female child