Development 05

7/26/2019 Development 05

1/35

Begins at puberty

Continues throughout

life


2/35


3/35


4/35


5/35


6/35


7/35

Triggered

by FSH


8/35


9/35


10/35

2) Enzymes released by exocytosis

) !crosomal process gro"s and binds to a receptor on #itelline layer$) Fusion of membranes causes opening of %a& channels

resulting in depolarization of membrane 'fast bloc( to

polyspermy)

) Entry of sperm causes cortical reaction* Signal transduction

causes Ca& release from E+ "hich causes cortical granules released

by exocytosis* Causes a s"elling and hardening of #itilline layer'becomes sperm proof fertiliztion membrane)


11/35


12/35


13/35


14/35


15/35


16/35


17/35


18/35


19/35

Clea#age

,rapid cell di#isions creating

many small cells'basically s(ip -. and -2

phases)


20/35

/n humans fertilization and clea#age occurs in the

o#iduct


21/35


22/35

Some animals 'frogs) ha#e

une0ual clea#age

1ol( concentrates in #egetal

pole,creates axes of body

,dorsal #s #entral

,anterior #s posterior

,left #s* right


23/35

-astrulation

Formation of layered embryo


24/35

Gastrulation

"It is not birth, marriage, or death, but gastrulation, which is truly

the most important time in your life."

e"is 3olpert '.456)7uring gastrulation8 cell mo#ements result in a massi#e

reorganization of the embryo from a simple spherical ball of cells8 the

blastula8 into a multi,layered organism* 7uring gastrulation8 many of

the cells at or near the surface of the embryo mo#e to a ne"8 moreinterior location*

The primary germ layers'endoderm8 mesoderm8 and ectoderm) are

formed and organized in their proper locations during gastrulation*

Endoderm8 the most internal germ layer8 forms the lining of the gut

and other internal organs* Ectoderm8 the most exterior germ layer8

forms s(in8 brain8 the ner#ous system8 and other external tissues*

Mesoderm8 the middle germ layer8 forms muscle8 the s(eletal

system8 and the circulatory system*

N t h d f


25/35

9granogenesis

,first to form are:,notochord

,neural tube

,somites

Notochordfrom

dorsal mesoderm ;ust

abo#e archenteron

,forms

#ertebral column

%eural tube from

neural plate that

rolls o#er on

itself,forms C%S

Somites : bloc(s of

mesoderm that run

along the notochord ,gi#e rise to

#ertebrae and

muscles of axial

'trun() s(eleton

#ideo
http://biology.kenyon.edu/courses/biol114/Chap14/Chapter_14.htmlhttp://biology.kenyon.edu/courses/biol114/Chap14/Chapter_14.html


26/35

Classic example of organogenesis and

induction in the de#elopment of the

#ertebrate eye


27/35

3ill form embryo and embryonic

membranes

Secretes enzymes that brea( do"n endometrium8 bathing

blastocyst in blood


28/35


29/35


30/35


31/35

Chorion surrounds all

other membranes

!mnion forms

amniotic sac

1ol( sac contains

no yol( 'early site

of blood cell

production)

!llantosis forms

umbilical chord

$ extaembryotic membranes


32/35

$ "ee(s


33/35

"ee(s

6 "ee(s


34/35

6 "ee(s


35/35

.6 "ee(s

Documents

Development 05