Gametogenesis Flashcards
What is a follicle?
An Ovarian structure that enables the ovary to fulfill its dual function
What is folliculogenesis?
Formation of the graafian follicle
What is follicle turnover?
Frequent emergence of new follicles
What is ovulation?
Release of oocyte from the graafian follicle
What are the seven events during follicular growth?
- Recruitment of follicles
- Selection of dominant follicle(s) and atresia of the remaining
- Nuclear maturation of oocyte
- Cytoplasmic maturation of oocyte
- Steroid synthesis
- Stigma formation
- Release of egg
What happens during the Recruitment of follicles during follicle growth?
cohort of follicles are selected
What is the Recruitment of follicles during follicle growth dependent on? how does it get it?
FSH - Theca interna has FSH receptors
What happens during the Selection of dominant follicle phase of follicle growth?
- LH receptors are developed in the granulosa cells
- remaining follicles undergo atresia
- steroidogenesis of estradiol
What happens during the Nuclear Maturation phase of follicle growth?
- Meiotic arrest until an LH surge is reached (stopped in prophase 1)
- Meiotic resumption until metaphase 2 where it stops again
What happens during the Cytoplasmic Maturation phase of follicle growth?
- Granulosa cells around the oocyte begin to loosen
- mRNA, proteins, substrates, and nutrients that are required to achieve oocyte and embryonic development accumulate
What happens during prophase 1?
Chromosomes pair
What happens during metaphase 1?
Paired chromosomes migrate to center due to centrioles
What happens during anaphase 1?
Chromosome pairs are separated and pulled to opposite ends of the cell
What happens during telophase 1?
Cell divides
What happens during prophase 2?
Centrioles duplicate and cell gets ready for another division
What happens during metaphase 2?
Chromosomes line up in the middle of the cell