Week 8 - Folliculogenesis and Oogenesis Flashcards
Primary Follicle
Oocyte surrounded by two or more layers of cuboidal granulosa cells and a zona pellucida
Secondary Follice
oocyte surrounded by ** multiple layers of cuboidal granulose cells**, thecal cells present, fluid beginning to form and zona pellucida around oocyte
Tertiary Follicle
oocyte surrounded by multiple layers of cuboidal cells, theca interna and externa present, fully formed antrum, corona radiata surrounding the oocyte and zona pellucida around oocyte
What is formed after ovulation?
CL
Corpus Luteum
- large mass of small and large luteal cell
- there can be “pockets” of fluid that remain
Luteolysis of the CL forms what?
Corpus Albicans
Corpus Albicans
-structure that remains following luteolysis (degradation of the CL)
- can be thought of as the “scar tissue” remaining following ovulation of a specific follicle
Atretic Follicle
- degenerative follicle
- can occur at any developmental step
- doesn’t get ovulated
What type of cells are present in the Multiplication Phase?
Primordial germ cells (2N) –> these are your stem cells
Multiplication Phase
- Rapid mitosis (cloning)
- these are your stem cells
- occurs before birth
Growth Phase
- occurs monthly in females in preparation of follicle/oocyte for ovulation
- primary oocyte (2N)
- Meiosis I occurs at the end of this phase
Where and why is Meiosis I halted?
Meiosis I is halted at Prophase I until ovulation
What separates the Multiplication and Growth Phases?
Mitosis
Maturation Phase
- following LH surge
- oocytes are no longer halted at Prophase I
- Marked by the 1st polar body extrusion and cumulus cell expansion
- oocytes are mature and ready for fertilization
What separates the Maturation Phase and Fertilization/Maternal-to-embryo Transition?
Meiosis II / OVULATION
