3. WHAT IS REPRODUCTION?
Reproduction is the process by which new organisms (offsprings)
are produced from organisms of the same kind.
Reproduction ensures the continuity of the species and keeps it
from becoming extinct. It plays a role in evolution as it creates
variations via genetic recombinations. It helps to increase the
number of species in the ecosystem.
5. ASEXUAL REPRODUCTION
Asexual reproduction is a mode of reproduction in which a new
offspring is produced by a single parent. The new individuals
produced are genetically and physically identical to each other, i.e.,
they are the clones of their parents.
Asexual reproduction is observed in both multicellular and
unicellular organisms.
7. FISSION
In fission body of an organism splits into two or more daughter
cells.
Types of fission
a. Binary fission
b. Multiple fission
8. BINARY FISSION FISSION
Binary fission is a form of asexual reproduction in which an organism
divides into two daughter cells identical to their parent.
Example : Amoeba
9. MULTIPLE FISSION
Multiple fission is a form of asexual reproduction in which an
organism divides into more than two ( many ) daughter cells
identical to their parent.
Example: Plasmodium
10. BUDDING
Budding is an asexual reproduction method in which a new
organism develops from a bud of an existing organism.
In budding, a new individual developed from a small part of the
parent called as bud. A bud that is formed during budding detaches
itself from the parent body and develops into a new organism. At
the time of separation, a new individual leaves scar tissue behind
them.
Small buds receive protein and nutrition from the parent hydra.
They grow healthy and their growth starts by developing mouth and
small tentacles. Finally, hydra separated from their parent body and
became an independent organism.
12. FRAGMENTATION
It is a type of Asexual reproduction which occurs in multicellular
organism with relatively simple body organization.
In fragmentation organisms on maturation breakup into two or
more small fragments or pieces called as fragment. Each fragment
subsequently grows to form complete new organism.
This process occurs under favorable conditions of moisture,
temperature and nutrient availability.
Example: spirogyra
14. REGENRATION
Regeneration is the ability to form new organisms from body parts.
Cut or broken part generates a new organism.
Example: Planarians
16. SPORE FORMATION
Spore formation is a form of reproduction in which the
reproductive bodies called the spores are present in a sac called the
sporangia. Once these spores mature the sporangia burst and these
matured spores reach different areas by air, wind and water. Under
suitable conditions, these spores germinate to form a new plant.
Example: Rhizopus fungus
18. VEGETATIVE PROPAGATION
It is a form of asexual reproduction seen in plants.
Vegetative propagation is a process in which plants reproduce from
stems, roots and leaves.
Layering and cutting are the two common methods used for
vegetative propagation. For example, banana, rose, jasmine etc.
The plant produced through vegetative propagation is genetically
identical to the parent plant.
20. GRAFTING
In grafting, two closely related plants are used to produce a new plant
that has the desired, combined traits of both the parent plants.
One plant is selected for its roots, and this is called the stock or
rootstock. The other plant is selected for its stems, leaves, flowers, or
fruits and is called the scion.
The scion contains the desired genes to be duplicated in future
production by the stock/scion plant.
The scion is attached to the stock of the second plant in this method of
artificial vegetative propagation.
Grafting is used in a variety of plants like roses, apples, avocado etc.