Basic Features of Reproduction

 

The biological process which allows the production of new organism from the existing organism is called reproduction.

 

Reproduction is the most fundamental attributes of all living organisms as it is essential for the survival of species it helps them to produce their on kind to maintain the life of their species on earth.

 

Basic Features:

Cell division-  A event which occurs during reproduction cell division. It is of two types

i.e Mitosis and Meiosis

 

Mitosis is a division in which replicated chromosomes equally distributed into two daughter nucleus so that the daughter cells have the same number and type of chromosomes as present in the parent cell it is therefore called equational division.

 

However, in Meiosis daughter cell formed have half the number of chromosomes as compared to the parent cell. So it is reductional division. Crossing over occur during the division, it introduces new combinations of genes or Re combinations which result in variations i.e degree of differences amongst progeny and between the program and the parents.

 

Duplication of cellular apparatus - before a cell divides all the Cellular apparatus must be duplicated so that cellular material present in parent cell can be equally distributed amongst two daughter cells. It involves replication of chromosomes in the nucleus which contain information for inheritance of features parents to next generation in form of DNA and involves formation of RNA, proteins and other bio chemicals.

 

Formation of Reproductive Units-

 

Reproductive units are specialised or non specialised parts of an organism which after of the separation or modifications results in the formation of new individual- offsprings.

 

There is a large diversity the biological world each organism has evolved it's on mechanism to multiply and produce offsprings. Both external (habitat) as well as internal (physiology) factors are collectively responsible for how it reproduces.

 

Broadly saying there are two types of reproduction, Asexual and Sexual

 
Asexual Reproduction-

It is mode of reproduction in which new individual develop from a single parent it is involvement of only one parent so it is uniparental it can occur without gametes formation but gametic fusion is absent. The individual the produced are exact copy of each other and there parent because the new organisms produced inherit all of its chromosomes from one parent. Morever, it involves only mitopic division.

 

Such a group of morphologically and genetically similar individuals is called Clone. It can occur through I am specialised or specialised parts of parent. It is widespread among different groups of organism it is common method of reproduction in organisms that have a relative simple organisation like single cell organisms belonging to group Monera, Protista as well as plants and animals with relativly simple organisation like Algae,fungi, sponges.

 

Though, it is a common mode of reproduction in lower organisms but it should be very clear that higher plants are also exits this type of reproduction where it is known as vegetative reproduction.