Flashcards
Developmental Biology I
Cards in this deck (21)
- 1Process of gamete formation (5)PCG originate in extra-embryonic tissue
Migrate into embryo via gut to genital ridge
Multiply by mitosis as they migrate
G.ridge gives rise to somatic cells of gonad
Divide by meiosis to form gametes - 2Spermiogenesis (7)1. Golgi develops into acrosomal cap
2. Cytoplasm extrudes
3. Flagellum develops
4. Mito coalesce near base of flagellum
5. Arg-rich protamines replace histones
6. Nucleus condenses
7. Cyto bridge lost. - 3Sperm tail structureSpecialised for motility
Axoneme has 2 central MT surrounded by 9 double MT - 4DyneinUses energy from ATP hydrolysis to slide MT past one another, causing flagella to lash.
- 5Egg specialisations"Yolk" nutrient reserve of PLC
Ribo + rRNA
mRNA
UV filters
Ez for DNA repair
EC glycoprotein coat. - 6Zona PellucidaMade of ZP1/ZP2/ZP3 glycoprotein
- 7ZP3Sperm receptor
Its O-linked ps determines species specificity - 8Why ZP3 knock-ins don't lead to fertilisation?Sperm doesn't recognise the murine polysaccharide
- 9Cortical granules are derived from ___ and contain ____ +____Golgi.
Proteases + Glycosidases - 10Outline processes of fertilisationPenetration
Binding
Acrosomal reaction
PCM fusion
Cortical reaction - 11PenetrationOocyte surrounded by cumulus cells in a matrix of hyaluronic acid
Hyaluronidase activity on sperm - 12BindingGaIT, a sperm GST, cross links to N-aga of ZP3
Clustering of GaIT + G proteins + mem pt. change
Opens V-Gated Ca2+ channels
IC [Ca2+] ^
Ca-mediated exocytosis on the acrosomal vesicle is initiated - 13Acrosomal reactionB-N-agadase + acrosin digest ZP
- 14Membrane bindingAcrosomal reaction exposes fertilin, an ADAM class protein, on sperm mem.
Binds to integrin-like R on oocyte PCM. - 15PCM fusionSperm Izumo and oocyte Juno proteins cause PCM to fuse.
- 16Egg responseRelease of Ca2+ from IC stores at 5-10ums-1
Followed by Ca2+ oscillations - 17Cortical reactionCa2+ triggers actin to polymerise form MT which transports CG to fuse w/ PCM
Release of CG enzymes via exocytosis
Partially digest ZP2, remove carb from ZP3
leads to ZP hardening, preventing polyspermy. - 18Meiosis IICa2+ + a kinase that digests cyclin, meiosis II is complete.
- 19Pronuclei fusionCentrosome forms from sperm centriole
Becomes MTOC for sperm aster
Oocyte extrudes 2nd PB
Pronuclei repicate DNA while they migrate along the MT to one another
N.envelope disintegrates
Centrosomes replicate + form mitotic spindle
mitosis takes place - 20What does the sperm provide?gamete
centriole - 21What does the ovum provide?gamete
mito
mRNA
proteins
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- Flashcards on Developmental Biology I, created by J yadonknow on 25/04/2018.
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- J yadonknow
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