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
#Most of the world''s flightless birds are either nocturnal and secretive (e.g. the kagu) or large, swift and well-armed (the ostrich). The exceptions are found primarily on island

Purpose of Supervision: Purpose: To help the personnel to grow, to know themselves and what they need in order to render the most efficient service and to give them assistance

Enzymes utilization in Brewing Industry Here, the main starting material is malt, produced by allowing barley seeds to germinate under moist conditions. The reserve starch is b

Hepaticae (Liverworts) The gametophyte is thalloid body or simple stem and leaves, with aquatic or semi-terrestrial habit. Rhizoids are multiceillular. Some examples : Mar

PAEDIATRIC NURSING   Parent education, family health promotion and health maintenance have been the concern of yesterday's and today's nurses. Florence Nightingale over a hu

Role of Private Sector in Health Care One of the biggest policy challenges for the government is to decide on the appropriate areas and a suitable policy framework for having

List three types of evidence used by systematic taxonomists to construct phylogenetic diagrams. Types of evidence contain the morphology of fossil and living species, patterns

Similarities in body parts often indicate shared ancestry. Which of the following is true? Structures used for different purposes in different groups can be controlled by the same

HMP shunt in erythrocytes HMP shunt in erythrocytes is of importance due to the generation of NADPH, which maintains the glutathione (G-SH)  in  the reduced  state by  glutathi

Do the arteries that carry blood from the heart to the lungs have arterial or venous blood? What happens to the blood when it passes through the lungs? Arteries of the pulmonar