Observe live hydra yourself and learn how they reproduce by doing the following activity:
During the summer months collect water weeds from ponds or ditches along with the pond water and put them in a glass jar. After a day or so you may see several hydra clinging to the sides of the jar.
Hydra is transparent, jelly-like and with tentacles. It clings to the jar with the base of its body. If the jar is shaken, the hydra will contract instantly into a small blob, at the same time drawing its tentacles in.
Now take out few hydras from the jar and put them on a watch glass. Using a hand lens or a binocular or dissection microscope, observe the changes that are taking place in their body. Note down your observations.
While observing under a microscope, the hydra changes its size and shape to under asexual reproduction. Hydra is an animal with tentacles and has a small outgrowth called bud on one side of its body.
During budding, a small bulb-like projection known as the bud develops on the body of the parent organism. The bud continues to grow on the parent until it develops and matures into a miniature adult.
After complete maturation, the bud pinches off from the parent's body and attains the ability to develop independently. The new Hydra detaches itself from its parent and starts living as a separate organism.
This bud gradually grows into a full hydra, developing its mouth and tentacles.
[Extra information:
Hydra is a fresh-water organism that belongs to the phylum Coelenterata and class Hydrozoa. They possess characteristics of a tube-shaped body with numerous tentacles present on the sides of the tube. It also possesses a radial symmetrical body and special stinging cells known as nematocytes that help feed. These organisms lack internal organs and a well-developed central nervous system.]
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