Gametogenesis to Neurulation Flashcards
5 Events of Early Embryogenesis
- Gametogenesis
- Fertilization
- Cleavage
- Gastrulation
- Neurulation
process of development and maturation of sex cells called gametes.
gametogenesis
the mature reproduction cells capable of fertilization.
Gametes
3 functions of structure and physiology of gametes.
- to survive in environment quite different from that of the gonad
- to recognize homologous cells of the other gender and participate in events related to fertilization
- provide sufficient genetic and cytoplasmic materials to support development of a new organism
refers to the development and maturation of female gamete (ovum)
Oogenesis
refers to the maturation and development of male gametes (spermatozoa)
spermatogenesis
the gonads in males
testes
specialized tubules inside the testes
seminiferous tubules
transformation of spermatids to spermatozoa
spermiogenesis
female gonads
ovaries
important process inside the ovaries
oogenesis
special stem cells found in the female individual
oogonia
where the nucleus of the secondary oocyte begins meiosis II progressing only to metaphase II, then division arrest
Ovulation
ensures that the endometrium is just the right layer and thickness for the developing embryo
Estrogen
3 types of ovum
•microelecithal egg
•mesolecithal egg
•macrolecithal egg
has no stored food material
spermatozoon
has stored food material in the form of yolk
ovum
the union of a haploid female gamete (oocyte) with a haploid male gamete (spermatozoon) to form diploid zygote.
Fertilization
where fertilization takes place
fallopian tube (oviduct)
penetrated by a single spermatozoon
ovum
it is the chromatin in the nucleus thickens into chromosomes
female pronucleus
chromatin in the head (nucleus) of the spermatozoon thickens into chromosomes
male pronucleus
series of cell division that occurs in the zygote following fertilization.
cleavage
2 types of cleavage
•holoblastic or equal cleavage
•meroblastic or discoid cleavage
occurs in mammals contains a small amount of yolk (isolecithal egg)
holoblastic or equal cleavage
occurs in birds and amphibians contains a large amount of yolk (telocithal egg)
meroblastic or discoid cleavage
large zygote if fractionated into numerous “normal size” cells
blastomeres
a solid ball of cells
morula
3 rapid transitional changes of morula
- increased number and compaction of blastomeres.
- transformation and rearrangement of blastomeres
- rearrangement of blastomeres results in the formation of blastocyst.
it develops during 2nd week following the rupture of the zona pellucida
blastocyst
surface cells of blastocyst
trophoblast
fluid-filled cavity
blastacoele