EMBBIOLOGY PROGENESIS
The science of the embryonic development from fertilization until
the end of first trimester
Embryo a multicellular diploid eukaryote 2n in early stage of
development
Phases of human embryogenesis
Progenesis Gametogenesis
Fertilization
Embriogenesis cleavage
Gastrulation
Neurulation formation of tube
Organogenesis
PROGENESIS gametogenesis
Development beginswith fertilization when the male gamate sperm
and female gamate oocyte unite to give rise to a zygote
Gametes are derived from Primordial germ cells PGC's that
are formed in epiblast mesoderm during second week move
through the primitive streak during Gastrulation migrate to the
wall of yolk sac indifferent stage
During 4th week cells migrate from the yolk sac toward the
developing gonads arrive at the end of 5th week
Mitotic devision increase their number during migration and also
when arrive to gonad
In preparation for fertilization agerm cell undergo gametogenesis
, n p eparation lo e Giza40 germ Ce undego gameLogeness
includes meiosis reduce the number of chromosomes and
cytodiferentiation acomplete maturation
GAMETOGENESIS
The process of mature male or female sex cells formation
Within the gonads the PGC's undergo several mitotic divisions
and then comin rice gametogenesis the timing of the process
of male 1female sex cell is different
1 Spermatogenesis male
Production of male gamates begin to develop by reaching
adolescence B and takes 4 stages
PGC's remain dormant in gonads shortly after birth of a boy
they differentiate into spermatogonial stem cells
d Mitotic proliferation A spermatogonia divide mitosisand produce
separate daughter cells the B spermatogonia divide mitosis
but remain linked by cytoplasmic bridges fr incomplete cytokenesis
2 Growth after mitotic proliferation spermatogonia B start
prophase meiosis 1 and recombain genetic material crossing over
form primary spermatocyte the largest nucleus with duplicate
DNA 2h14C crossing over are men
3 Maturation mieosis Hit divisions resulting in 4 different cells
primary spermatocyte
2h14C 92 Chromosomes
23 4 Diploid
t meiosis I
2 secondary spermatocytes
4h12C 46 chromosomes
23 2 Haploid meiosis 11
, 23 2 11apt d met sis i
a
4 spermatids
thHc 23 chromosomes
23 1 haploid cell Haploid
4Formation of spermiogenesis condensation of nucleus A Acrosome
formation cytoplasm removal acquisition of neck with centrioles
tail with mitochondria in the midpiece and microtubules in the
long end for movements
spermatozoon is
arranged to promotemobility 1
Acrosome 2
Head
NeckMidpiece 3
Thy Tail
4
Equatorial region is where
plasma membrane of sperm and
inner acrosomal membrane meet
Supporting cells Sertoli cells on
cell function FSH receptors on the membrane inhibin production
ABP synthesis Androgen Binding Protein diffrentiation gametes
unique cytoplasmic processes of mature spermatocytes link with
the cells cytoplasm allows Spermiation release of sperm into
lumen tubules
The cell connect each other by
Occuloding junctions 053 divide seminiferous tubules wall into 2
compartment include the interstitial space and the
i Basal
sperma
space of spermatogonia It is between sertoli cells and
basement membrane BMI
2 Adulminal compartment include the tubule lumen and intercellular
The science of the embryonic development from fertilization until
the end of first trimester
Embryo a multicellular diploid eukaryote 2n in early stage of
development
Phases of human embryogenesis
Progenesis Gametogenesis
Fertilization
Embriogenesis cleavage
Gastrulation
Neurulation formation of tube
Organogenesis
PROGENESIS gametogenesis
Development beginswith fertilization when the male gamate sperm
and female gamate oocyte unite to give rise to a zygote
Gametes are derived from Primordial germ cells PGC's that
are formed in epiblast mesoderm during second week move
through the primitive streak during Gastrulation migrate to the
wall of yolk sac indifferent stage
During 4th week cells migrate from the yolk sac toward the
developing gonads arrive at the end of 5th week
Mitotic devision increase their number during migration and also
when arrive to gonad
In preparation for fertilization agerm cell undergo gametogenesis
, n p eparation lo e Giza40 germ Ce undego gameLogeness
includes meiosis reduce the number of chromosomes and
cytodiferentiation acomplete maturation
GAMETOGENESIS
The process of mature male or female sex cells formation
Within the gonads the PGC's undergo several mitotic divisions
and then comin rice gametogenesis the timing of the process
of male 1female sex cell is different
1 Spermatogenesis male
Production of male gamates begin to develop by reaching
adolescence B and takes 4 stages
PGC's remain dormant in gonads shortly after birth of a boy
they differentiate into spermatogonial stem cells
d Mitotic proliferation A spermatogonia divide mitosisand produce
separate daughter cells the B spermatogonia divide mitosis
but remain linked by cytoplasmic bridges fr incomplete cytokenesis
2 Growth after mitotic proliferation spermatogonia B start
prophase meiosis 1 and recombain genetic material crossing over
form primary spermatocyte the largest nucleus with duplicate
DNA 2h14C crossing over are men
3 Maturation mieosis Hit divisions resulting in 4 different cells
primary spermatocyte
2h14C 92 Chromosomes
23 4 Diploid
t meiosis I
2 secondary spermatocytes
4h12C 46 chromosomes
23 2 Haploid meiosis 11
, 23 2 11apt d met sis i
a
4 spermatids
thHc 23 chromosomes
23 1 haploid cell Haploid
4Formation of spermiogenesis condensation of nucleus A Acrosome
formation cytoplasm removal acquisition of neck with centrioles
tail with mitochondria in the midpiece and microtubules in the
long end for movements
spermatozoon is
arranged to promotemobility 1
Acrosome 2
Head
NeckMidpiece 3
Thy Tail
4
Equatorial region is where
plasma membrane of sperm and
inner acrosomal membrane meet
Supporting cells Sertoli cells on
cell function FSH receptors on the membrane inhibin production
ABP synthesis Androgen Binding Protein diffrentiation gametes
unique cytoplasmic processes of mature spermatocytes link with
the cells cytoplasm allows Spermiation release of sperm into
lumen tubules
The cell connect each other by
Occuloding junctions 053 divide seminiferous tubules wall into 2
compartment include the interstitial space and the
i Basal
sperma
space of spermatogonia It is between sertoli cells and
basement membrane BMI
2 Adulminal compartment include the tubule lumen and intercellular
