Distinguish between the sex chromosome complements of human female and male germ-line cells at different stages of gametogenesis.

Gametogenesis is the formation of gametes, in males it is referred as spermatogenesis and in females it is called oogenesis.

Explanation:

Differences between spermatogenesis and oogenesis:

1. Spermatogenesis is formation of sperms from spermatogonia and oogenesis is formation of ova from oogonium.

2. Location: Production of sperms occur in testis and production of ova occurs in ovaries.

3. In males, spermatogenesis begins at puberty and its a continuous process till death whereas in females, oogenesis begins at fetal stages, it halts and rest of the process occurs after puberty till menopause.

4. Primary spermatocyte undergoes meiosis-I to form two secondary spermatocytes, whereas primary oocyte undergoes to M-I to form a single secondary oocyte with a polar body.

5. Meiosis-II results in the formation of 4 spermatids or spermatozoa, in females however M-II results in only one ovum and second polar body formation.

6. Overall we can say that single spermatogonium forms 4 spermatids whereas single oogonium forms only 1 ovum.

7. Sperms are motile where as ovum in non-motile.