What is one difference between a primary oocyte and a secondary oocyte in humans?

Sagot :

1.primary oocytes 
- diploid (2 complete sets of chromosomes) 
- 'formed' from oogonia during the process of oogenesis 
* primordial follicles consist of a primary oocyte + a single layer of squamous follicle cells 
* primary follicles consist of a primary oocyte + 1/several layers of cuboidal follicle cells 

2. secondary oocytes 
- haploid (1 complete set of chromosomes) 
- developed from the primary oocyte undergoing meiosis I to form a secondary oocyte + a tiny first polar body 
* found in the matured Graafian follicle 
* begins meiosis II & stops at metaphase II upon ovulation & only continues upon fertilisation

Assuming the options are:

-> A. A primary oocyte contains 46 chromosomes, while a secondary oocyte contains 23 chromosomes.

B. A primary oocyte is produced after birth, while a secondary oocyte is produced before birth.

C. A primary oocyte develops in both men and women, while a secondary oocyte develops only in women.

D. A primary oocyte is the product of meiosis, while a secondary oocyte is the product of mitosis.