A brief introduction to life span and reproduction.

1. R E P R O D U C T I O N I N
O R G A N I S M S
- N I D H I TAYA L

3. Now, what is REPRODUCTION ?
Like if we say in basic terms, RE-PRODUCTION simply means process of
recreation of a similar kind of individual to that of existing individual.
DEFINITION:
• Reproduction is defined as a biological process in which an organism
gives rise to young ones (offspring) similar to itself.
• The offspring grow, mature and in turn produce new offspring.
offspring.
• Thus, there is a cycle of birth, growth and death.

4. WHY DO WE NEED THE PROCESS OF REPRODUCTION ?
• Each and every organism can live only for a certain
period of time.
• The period from birth to the natural death of an
organism represents its life span.
• In order to maintain continuity of life , reproduction
becomes essential .
Reproduction enables the continuity of the species,
generation after generation.

5. LIFE SPAN
• Life span varies from individual to individual and to species of
different organisms.
• It does not depends on size of the individual. For example: I n crow
and parrot, the size has a negligible difference but the life span
varies a lot.
Crow (15 years) Parrot(140years)

6. LIFE SPAN OF VARIOUS
ORGANISMS

7. • Whatever be the life span , the death of an
individual is certain; no one is immortal.
• However, an exception to this are the unicellular
organism who do not have a natural death , but
similar daughter cells.
• The division of unicellular organisms and various
types of reproduction will be discussed in further
videos of the chapter.