Fertilisationnnnnnn Flashcards
Fertilisation
During copulation (), semen is released by ()
The _______ sperms swims , pass , enter into , finally reach
Site of fertilisation
Fusion of haploid male gamete with haploid female gamete to form diploid zygote
coitus , penis into vagina ( insemination)
Motile rapidly, through cervix , uterus, ampullarh region of fallopians tube
Ampullary region of fallopians tube
Capacitation ( duration
These occur in
Why not all copulation lead to fertilisation and pregnancy
Arrival of sperm movement
Of secondary occyte
Multiple changes that activate sperm for final processes of fertilisation (5-7hr
Sperm on coming in contact with fluids of female genital tract
It can only occur if ovum and sperms are transported simultaneously to ampullary region
Flagellar , ciliated , prostaglandin
Ciliary
Fertilization in male
Male -> insemination ( transfer of male gamete into female reproductive tract) -> capacitation of sperm (5-7 hr ) removal of deposit substance from acrosome , entry of ca+2 ion -> arrival of sperm into uterus through cervical canal -> movement of sperm into fallopians tube
Female
Acrosomal reaction
Release secondary oocyte -> ovulation -> arrival of secondary oocyte into fallopians tube through infundibulum-> fallopians tube ( ampullary region ) -> fertilisation
Hyaluronidase enzyme = break cementing layer
Corona penetrating enzyme = digest corona radiating layer
Zona lysin enzyme (acrosin) = digest zona pellucida layer
Fertilization main events in sequence and their definition
Syngamy = union of male and female gamete
Plasmogamy = intermixing of cytoplasm of male and female gametes
Karyogamy = fusion of pronuclei of male and female gamete
Amphimixis = intermingling of chromosomes of male and female gamete
Fast block polyspermy
Slow block polyspermy
The secretion of acrosome help sperm to enter
Phagocytosis of sperm by, during which
Generation of action potential
Due to cortical reaction
Into cytoplasm of ovum through zona pellucida and plasma membrane
Secondary oocyte , completion of second Meiotic division of secondary oocyte to form ovum and second polar body
Cortical reaction produces , ensure
Not dissolved in cytoplasm
Sex of baby determined by
Changes in zona pellucida ( makes it hard) that block the entry of additional sperm , only one sperm fertilise the ovum
Nucleus and proximal centriole
Father
Cleavage =
,,,, ( moves through ___cell called
Interphase , results into
1 st cleavage
2nd
Repeated Mitotic division
The Mitotic division starts as zygote moves through isthmus of oviduct called cleavage toward uterus and forms 2,4,8,16 daughter cells called blastomeres
Short , ( s phase present) , multicellular embryo without any change in overall size
30 hrs
40 hrs
Morula ,structure ,name , layer
Blastula / ,
Outer layer , inner
What contain stem cell , cavity
Embryo with 8-16 blastomeres , solid ball like, resembles mulberry fruit,zona pellucida
Blastocyst = 64 cell stage
Trophoblast , inner group of cell attached to trophoblast called inner mass / embryoblast
Inner cell mass , blastocoel
Blastocyst outer layer gets attached to , inner mass
Embryblast cell attached to trophoblast call
Trophoblast/ responsible for
Endometrium , differentiate as embryo
Cell of rauber,
Trophoectoderm for placenta formation
Implantation , starts
Completion , site
Ectopic Pregnancy , by
Attachment of blastocyst to endometriosis lining of uterus , 1 week after fertilisation
By day 12 after fertilisation , fundus part
Implantation other than uterus , zona pellucida
Decidua , layers
Gastrulation , formation of ( 1st ,2nd,,
Movement
Trophoblast later forms
Embryoblast
Uterus of pregnant mother , decidua basalia , decidua capsularis , decidua parietalis
Transformation of blastocyst into gastrula , 3 germ layer ( endoderm , ectoderm , meso
Morphogenetic
Cytotrophoblast , syncytotrophoblast
Epiblast ( long columnar) , hypoblast ( short cuboidal
Formation of ____… embryonic,,,
Formation of primitive steak (movement)
Fate of germ layer ectoderm
Mesoderm
Endoderm
Bilayer , disc
Invagination = epiblast - ectoderm. Hypo some epi = Endo (1st) , middle = meso
Nervous system, sensory organs
Circulatory , excretory , skeletal, reproductive
Digestive , respiratory
Bilaminar embryonic disc
Amniogenic cell from
Formation of yolk sac what formed
Extra embryonic ______ from
Epiblast + hypoblast
Trophoblast
Primary yolk sac and endodermal cells of yolk sac
Mesoderm , trophoblast
Formation of extra embryonic coelom peripheral region cell , 2 cell near, cavity (name ) formed between
Chorion outer, inner
Fn
Chorionic frondosum
Somatopleuric extra embryonic mesoderm , splanchnopleuric extraembryonicmesoderm
Extra embryonic coelom ( endodermal cell of yolk sac & 1cell
O= endoderm , i = mesoderm
Involve in placenta formation, secrete placental formation
Part of chorion which help in formation of placenta
Amnion outer ,inner
Fn
Yolk sac outer ,inner
Fn
What is same as yolk sac
O= mesoderm , I=ectoderm ,
Act as shock absorber ,prevent from desiccation
O= mesoderm, in=endoderm
Formation of blood cells in early embryonic stage
Allantois
Extra embryonic coelom
Space b/w chorion and amnion
Organogenesis end of 1 month
Of 2 month
Of 3 3 month / /
5 month
Embryo heart Is formed
Limbs and digits develop
1 trimester / 12 weeks = most of organs are formed , ( limbs , genetial more developed
Appearance of hair on head , first movement start
Endo of 6 month //
End of 9 month /
Placenta
Characteristics of placenta
24 weeks , 2 trimester = eyelids separate / eyelashes are formed
3 trimester = foetus Is fully developed, ready for delivery
Intimate connection b/w material tissue ( uterine tissue ) and developing foetus
Haemochorial placenta
Metadischorial placenta
Deciduous placenta ( child + placenta
Chorionic villi , surrounded by
Chronic villi & uterine tissue forms a
Umbilical cord , fn
After implantation, finger like projection appear on trophoblast , uterine tissue and maternal blood
Structural and functional unit between developing embryo (foetus)& maternal body
The placenta is connected to embryo through ,
Helps in transport of substance to and from embryo
Fn of placenta ,
,
,
,
,
Placental hormone ,,,,,
Nutrition
Exchange of gases
Removal of waste
Act as barrier
Act as endocrine gland
hcG ( humanchorionic gonadotropins) , hpL( human placental hormone) , progesterone,
Estrogen , relaxin
hcG =
2
3
hpL =/
Fn
Humanchorionic gonadotropins = stimulates corpus luteum for secretion of progesterone & estrogen
Helps prepare mammary gland for lactation
Maintains endometrium during pregnancy
Human placental lactogen / human chorionic somatomammotropin (hCS)
Responsible for development of mammary gland during pregnancy
Relaxin fn
2
3
Crh fn
2
Dilate pelvic muscle (ileocaceal muscle ) , help in parturition
Increases flexibility of pubic symphysis
Helps dilate uterine cervix during labour
Corticotropin releasing hormone = establishes timing of birth
Increases secretion of cortisol
What are produced only during pregnancy
During pregnancy hormones increased
Essential for
hCG , hPL, relaxin
Estrogen, progesterone, cortisol, prolactin , thyroxine , hcG,hpL
Supporting foetal growth, metabolic changes in mother, maintained of pregnancy
Teratogene
Pregnancy test
Gestation period
Human
Cat
Dog
Elephant
Certain agents which cause foetal abnormalities eg certain viruses, drugs , alcohol
Grovidextest
Duration b/w copulation and child birth
9 months +- 7 days ( 270-290 days )
63-65 days
60-65 days
607 - 641 days
Parturition / , mechanism , hormones like
Important components of initiation of parturition
Foetal ejection reflex
Child birth , complex neuroendocrine mechanism , Crh , cortisol , estrogen, oxytocin,relaxin
Increase in estrogen and progesterone
Signals for parturition originate from fully developed foetus and placenta which induce
Mild uterine contractions
Parturition
,
,
,
,
,
,
Generation of foetal ejection reflex
Stimulate maternal posterior pituitary
Secretion of oxytocin hormone
Contact myometrin wall of uterus
Secretion of relaxin from placenta
Dilution of pelvic muscle
Child birth
Stage of parturition
1 ) duration
Stage of dilation ( 8-12 hrs) = release oxytocin
Contract myometruim lining of uterus
Release relaxin
Dilation of pelvic muscle
2 stage =
3 stage
Lactation prolactin fn ,,
Oxytocin ,,,
First mother milk , immunity
Of expulsion ( 10 min) = expulsion of foetus through birth canal
Placental stage
Milk producing , milk secreting hormone
(Milk let down) Milk ejecting / birth hormone , labour pain
Colostrum (IgA) = passive
Twins
Monozygotic/ identical twins
Dizygotic / non identical twins/ fraternal twins
Conjoint / Siamese twins
Gastrulation stage
Formation of bilayer embryonic disc
Formation of amniotic cavity
Formation of yolk sac
Formation extra embryological mesoderm
Formation of extra embryonic coelom
