Fertilization To Trilaminar Flashcards
What does the sperm penetration of the egg also trigger?
Second meiotic division
Go through 4 stages of fertilisation
Sperm binds with zona pellucida glycoprotein
Acrosomal enzymes released from sperm head- sorry digests its way into egg
Egg and sperm pm fuse and sperm empties contents into egg
Sperm entry triggers cortical granule release in egg cortex triggering fertilisation membrane formation which is then impenetrable
Fusion of male and female pronuclei is called what?
Zygote
What is cleavage
Zygote undergoes several mitotic divisions
What are blastomeres?
When a fertilised egg subdivides into many smaller daughter cells
What is blastocyst formation?
Some mitotic divisions
How long does it take to implant?
Up to 6 days
What does the Inner cell mass give rise to?
The embryo
What do the other cells give rise to?
Trophoblast which contributes to the placenta
Where are embryonic stem cells derived from?
ICM
At the 8-12 day mark, what does the syncytiotrophoblast contact
Maternal blood supply
Where is the amniotic cavity?
Above the embryonic disc
What is below the embryonic disk
Yolk sac
What encircles the entire embryo?
Chorionic cavity
What are the 2 layers of embryonic disks called?
Epiblast
Hypoblast
What 3 layers become of the epiblast and hypoblast?
Ectoderm
Mesoderm
Endoderm
What does the hypo last become?
Endoderm
What does the ectoderm turn into?
Epidermis of skin
Nervous system
What happens to the mesoderm
Divided into 3 layers- paraxial, intermediate and lateral plate
What happens to the endoderm
Becomes the lining of the gut and respiratory tract
What does the intermediate mesoderm do?
Part of the urogenital system
Lateral plate mesoderm?
Lining of body wall, limbs ect
Visceral: covering of organs cardiovascular system
