Embryology Week 1 Flashcards
What is oogenesis?
formation of eggs
What is spermatogenesis?
formation of sperm
Where does spermatogenesis occur?
seminiferous tubules
What are spermatogonia?
primordial germ cells
What are the 3 major spermatogenesis steps?
- mitotic proliferation 2. meiosis 3. packaging
What happens in mitotic proliferation?
each spermatogonium duplicates to form Type A and Type B daughter spermatogonia
What are type A spermatogonia cells?
undergo self renewal and reserve stem cell
What and where does type B become what it needs to be?
pushed toward lumen where it becomes a primary spermatocyte - destined to produce 4 sperms
What does the primary spermatocyte become after it undergoes meiosis 1?
2 secondary spermatocytes - haploid cells
What does it then become after meiosis 2?
4 spermatids
What is spermiogenesis?
differentiation of newly formed spermatids to spermatozoon
What is the function of sertoli cells?
- provide nutrients for spermatds 2. help shed superfluous cytoplasmic baggage
What does the head of the sperm contain?
haploid nucleus + acrosome with hydrolytic enzymes + protamines
What does the midpiece contain?
mitochondria
What does the tail contain?
flagellum for locomotion
Explain the Kartagener Triad?
no dynein - defective movement of cilia
Effect of Kartagener Syndrome?
- recurrent chest infections - bronchial infections 2. ear/nose/throat symptons 3. heart on the right side - dextrocardia
Which sperm is less resistant to acidic condition? LY - lie
Y sperm
Which sperm is more resistant to acidic condition? MX - mix
X sperm
When does oogenesis begin?
before birth - primordial germ cells differentiate into oogonia
When does oogenesis occur?
after primordial germ cells arrive in ovary
In the 3rd week where do primordial germ cells appear?
wall of the yolk sac - close to allantois
Where do the primordial germ cells move along?
migrate along dorsal mesentry of the hindgut - to invade genital ridges
What is atresia?
the process that occurs when oogonia stops and never resumes, but cell death happens
What is fertilization? Where does it occur?
process by which male and female gametes fuse - occurs in ampullary region of uterine tube