Fundamental characters of embryonic development, Biology

FUNDAMENTAL CHARACTERS OF EMBRYONIC DEVELOPMENT

1.       GAMETOGENESIS-

Testes & ovaries are collectively called as gonads. Similarly sperms & ova are collectively called as gametes. The formation of gametes in the gonads is called as gametogenesis.

Gametogenesis is of 2 types -

(a) Spermatogenesis - formation of haploid sperms in the testes.

(b) Oogenesis - formation of haploid ova in the ovaries.

2.       FERTILIZATION

Fusion of haploid ova & sperms to form diploid zygote is called as fertilization. The sperm activates the ovum to develop.

3.       CLEAVAGE

It is a sequence of mitotic divisions which results in the formation of multicellular morula. The resulting cells are called as blastomere.

Cleavage is a type of mitotic division, resulting unicellular zygote convert into multicellular structure.

Formation of blastula through zygote, this process is called blastulation.

4.      GASTRULATION

The cells of blastula exhibits morphogenetic movements to form a triploblastic structure called gastrula. The process is called as gastrulation.

The blastocoel is lost gradually and a gastrocoel is formed.

The three germ layers formed in gastrula are ectoderm, mesoderm & endoderm.

A cavity present in the gastrula is called as Archenteron.

5.      ORGANOGENESIS

The germ layers form various organs, Firstly, they form small groups of cells which are called as primary organ rudiments.

The primary organ rudinents form secondary organ rudimetns which finally form tissues & organs in adults.

6.      GROWTH

The tissue & organs after formation exhibit grwoth & increase in volume.

The growth is due to constant mitosis and sythesis of nuclear & cytoplasmic materials. Gradually, the embryo grows & take the parental shape.

7.      DIFFERENTIATION

The growth of embryo is accompanied with differentiation which is of three types -

(a) Histological differentiation

(b) Chemical differentiation

(c) Physiological differentiation

8.      METAMORPHOSIS

Posted Date: 10/3/2012 7:08:41 AM | Location : United States







Related Discussions:- Fundamental characters of embryonic development, Assignment Help, Ask Question on Fundamental characters of embryonic development, Get Answer, Expert's Help, Fundamental characters of embryonic development Discussions

Write discussion on Fundamental characters of embryonic development
Your posts are moderated
Related Questions
A classical secretory protein vary from a cytosolic protein by having a sequence about 13-35 amino acids long at its N-terminal end called as a signal peptide or signal sequence.

Q. Etiologic factor of ulcerative colitis? No single etiologic factor has been identified although genetic auto-immune factors are thought to be involved. Although exacerbation

Carbohydrate Digestion Simple sugars like glucose and fructose can be absorbed and metabolised directly but disaccharides such as sucrose or lactose and polysaccharides such a

Q. How is the yolk sac formed? What is the function of the yolk sac? The yolk sac is formed from the covering of the vitellus by few cells originated from the primitive gut.

Sedge-Meadow Stage - Hydrarch Favoured by an increasing amount of light, as the former occupants disappear, they gradually change the reed swamp into a sedge meadow. And now s

Q. Write the meaning of diabetes mellitus? The word "diabetes" is from the Greek word meaning "a siphon". Diabetes patients had polyuria (passing excessive urine) and "pass it

Indication of Exchange Transfusion i) Early exchange transfusion is indicated in the presence of hydrops and is often indicated by a history of previously severely aff

Explain the Primary Root Growth? Primary Growth in Roots :  Roots grow down and through the soil by adding new cells at the tip of the root (called the root tip). There is a

what is the function of dna primer

Counseling Strategies The counseling strategies which may serve  lo be useful are described herewith. Individual Counseling: Individual counseling is personal counseling.  T