2a Embryonic Development.ppt

7/24/2019 2a Embryonic Development.ppt

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Survey of Embryonic

Development


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Human Anatomy and Physiology,7eby Elaine Marieb & Katja Hoehn

Copyright 27 !ear"on E#ucation$ %nc$publi"hing a" 'enjamin Cumming"

Diagrams showing the size of a human conceptus from fertilization to the early fetal stage

Fertilization1-week conceptus

2-week conceptus

3-week embryo

Embryo

4-week embryo

5-week embryo

-week embryo

!-week embryo

"-week embryo

#-week fetus

12-week fetus


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$perm penetration an% the cortical reaction &slow block to polyspermy

Fusion of oocytean% sperm plasmamembranes

'orticalreaction

$perm nucleus engulfe%by oocyte cytoplasm

(ocyte cytoplasm'ortical granule

(ocyte plasmamembrane

E)tracellularspace

*ona pelluci%a

$perm nucleus

+ranulosa cellsof corona ra%iata

,crosomalreaction

,crosome

(ocyte insecon% meiotic%iision

First polar bo%y

*ona pelluci%a'orona ra%iata$perm

&a.

&b.


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Eents imme%iately following sperm penetration

Daughtercells

,naphase offirst cleaage%iision

$perm an% oumchromosomes

*ygote

/ale pronucleus

/itotic spin%le

'entriole

Female pronucleus

0olarbo%ies

(um

nucleus

$perm pro-nucleus

Detache%sperm tail

$perm

E)tracellular space

$econ% meiotic %iisionof oocyte

$econ% meiotic %iisionof first polar bo%y

'oronara%iata

*onapelluci%a

&a.

&b.

&c.

&%.

&e.

&f.

&g.

&h.


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lastocystcaity

Degeneratingzonapelluci%a

nner cellmass

lastocystcaity

rophoblast

*ygote&fertilize%egg.

4-cell stage2 %ays

/orula3 %ays

Early blastocyst4 %ays

mplanting blastocyst %ays

'aity ofuterus

terus

En%ometrium(ulation

(ary

Fertilization&sperm meets egg.

terine tube

(ocyte&egg.

$perm

&a. &b. &c. &%. &e.

&a.

&b.

&c.

&%.

&e.

'leaage from zygote to blastocyst


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mplantation of the blastocyst

En%ometrial stromawith bloo% esselsan% glan%s

$yncytiotrophoblast

'ytotrophoblastnner cell mass&future embryo.

8umen of uterus

terine en%ometrial

epitheliumnner cell mass

rophoblast

En%ometrium

lastocyst caity8umen of uterus

&b. &c.

&a.


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Formation of the three primary germ layers

ilayere%

embryonic %isc

,mniotic sac

,mniotic sac &amnion.9olk sac

'ut e%ge

of amnion

8eft

7ight

0rimitiestreak

ypoblastEpiblast

9olk sac

Future openingbetween mouthan% pharyn)

ea%

&b. : : : turne% #6;&c. 3-D iew &%. $ection iew in &e.

&a. Embryo&$ee Figure 2":!b.

&e. ilayere% embryonic %isc< lateral-superior iew

9olk sac

ail


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Formation of the three primary germ layers

ea%

'ut e%geof amnion

9olk sac&cut e%ge.

7ight8eft

$ections

ail

0rimitie streak

0rimitie

streak

En%o%erm

/eso%erm Definitieen%o%erm

Epiblastypoblast

Ecto%erm

&f. ilayere% embryonic

%isc< superior iew

&g. 14=15 %ays

&h. 1 %ays


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>eurulation

&a. 1! %ays

&b. 1# %ays

,mnion

,mniotic caity

>eural plate

Ecto%erm

/eso%erm

>otochor%

En%o%erm

9olk sacail

ea%

'ute%ge of

amnion

0rimitiestreak

$urfaceecto%erm

>eural

plateFutureneural

crest

>otochor%

>otochor%

'ut e%ge

of amnion>eural

plate

0rimitieno%e0rimitiestreak

>eural grooe>euralfol%

>euralgrooe >eural

crest

8eft 7ight


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(i""ue" #erive# from the three

germinal layer") Ecto#erm* nervou" ti""ue"$ epi#ermi"

an# melanocyte"

) Me"o#erm* bone"$ mu"cle"$me"enchyme$ repro#uctive "y"tem$

urinary "y"tem

) En#o#erm* #ige"tive "y"tem$ re"piratory"y"tem$ en#ocrine "y"tem


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Eents of placentation< early embryonic %eelopment< an% e)traembryonic membrane formation

/aternalbloo% essels

8acuna &interillusspace. containingmaternal bloo%

Endometrium

,mniotic caity

0rimarygerm layers?

@ Ecto%erm'horionic illus

'horion

,mnion

9olk sac

E)traembryonicmeso%erm

'horionbeing forme%

Lumen of uterus

0roliferatingsyncytiotrophoblast

'ytotrophoblast

,mniotic caityilayere%embryonic%isc?@ Epiblast@ ypoblast

En%ometrialepithelium

@ /eso%erm

@ En%o%erm

Forming

bo%y stalk,llantois

E)tra-embryoniccoelom

&a. !1A2-%ay implanting

blastocyst

&b. 12-%ay implante% blastocyst

&c. 1-%ay embryo


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Embryonic membrane"

) +mnion* enca"e" an# protect" embryo

again"t mechanical an# temperature

trauma) ,ol- "ac* tran"fer" nutrient" to embryo

.eplace# by placenta in human"

) +llantoi"* repo"itory of embryo /a"te".eplace# by placenta in human"


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Deci%ua basalis

/aternal bloo%

'horionic illus

mbilical bloo%essels inumbilical cor%

,mnion

,mniotic caity

9olk sac

E)traembryonic

coelom

'horion

Deci%uacapsularis

Lumen

of uterus

&%. 41A2-week embryo



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0lacenta

Deci%ua basalis

'horionic illi

9olk sac

,mnion

,mnioticcaity

mbilical cor%

terus

8umen ofuterus

Deci%ua

capsularis

&f. 13-week fetus

E)traembryonic

coelom


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/yometrium

/aternaleins

/aternalarteries

mbilical arteries

mbilical ein'onnection toyolk sac

'horionic illuscontaining fetalcapillaries

Fetal arterioleFetal enule

,mnion

&g.

mbilical cor%

/aternal bloo%in lacuna

&interillus space.

$tratum basalis ofen%ometrium

/aternal portion

of placenta&%eci%ua basalis.

Fetal portion ofplacenta &chorion.

2a Embryonic Development.ppt

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