Concept of developmental/Embryology biology:
It is a study of the process by which plant and animals grow and develop. It is also includes the biology of regeneration, asexually reproduction, metamorphosis, and growth and differentiation of stem cell in the adult organism.
“It is the study of early development from the Zygote (Fertilized egg) to the appearance of definite organism, it is called embryology/developmental biology”.
Growth:
Growth is a fundamental characteristic of all living organisms. It is simply as an increasing in size.It is achieved by increased rate of cell division involving Fresh synthesis of nuclear material and protein synthesis.
It is also defined as growth is an irreversible increase in dry mass of living material.The process of development is closely linked with growth that is development occurs through growth.
Differentiation:
Differentiation is the process in which the cells or other parts of an organism acquires or become different from one another and also different from their previous condition.
Development involves growth and differentiation.
Every cell is capable of performing the process of metabolism (respiration, synthesis, and so on).
The basic function of life which are common to all living cells (ability of amoeboid movement, irritability and able to react to extend stimuli).
These are found in both undifferentiated and differentiated cells.
Now, but differentiated cells are able to perform special functions or to perform them in such a way that other cells cannot.
E.g.
1) nerve cells are capable of conducting nerve impulse to brain distance and at high speed.
2) The liver cells secrets bile.
3) The melanophore produce granules of melanin pigment in there cytoplasm.
De-differentiation:
De-differentiation may be reversible to certain extend.
The morphological and physiological peculiarities of tissue require for the maintenance of environment which surround them in a normal organism.
The cells derived from different tissue but they may acquire very similar appearance.
An appearance not unlike that the cell which have not yet undergo differentiation, this phenomenon called De-differentiation.
Regeneration:
It is a second mode of reawaking morphogenetic process, it is advanced stage.It is the process by which some organisms replace or restore lost body parts.
For example: organism possesses ability to repair more or less damage or wound, damage may involve loss of organ or larger part of body. These can be sometimes renewed and in this case the process of repair is known as Regeneration.
“In biology regeneration is the process of renewal, restoration, and growth that make genome , cells, organisms, and eco-system. Resilient to the natural fluctuation or event that cause damage or disturbance.
Induction:
Embryonic induction describe the embryonic process in which one group of cell i.e. the inducing tissue, direct the development of another group of cell, i.e. Responding tissue.
Induction directs the development of various tissue and organs in most animal embryo.
Example: The eye lens and the Eye I.e. in development induction. Is the ability of one cell or tissue to direct the development of neighboring cell or tissue. The famous example is Spemannin and Mangold experiment. During very early development there id spot on the blastopore known as organizer.
Organizer:
It is an embryonic tissue which organizes the surrounding tissue to develop embryo I.e. organizers influence organize other tissue to differentiate and produce the structure or organs.
Fate map (Presumptive organ forming area):
A chart or Map or Topographical surface showing the fate of each part of an early embryo in particular blastula is called Fate Map. It is a technique used to understand how the embryonic cell divides, differentiated and migrate during development.
Totipotency:
It is a ability of all single cell or cell group to give origin (produce) all differentiated cells and tissue to form entire organism. In Mammals only the zygote and sub-sequent blastomer are the totipotent.
Example: Embryonic Stem Cell: - great ability to differentiate into any type of body part.