Tenth Grade Biology: Hydras.. Please help!!!?

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Kris

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Ok please help me with these questions on hydras:

Describe the symmetry found in a hydra. Describe how a hydra catches, eats and digests a small organism. How does sexual reproduction take place in a hydra? Why is the winter egg production by a hydra an adaptive advantage for species living in cold climates? Why is a hydra said to have no true tissues even though it has specialized cells?

Thanks so much!
 
Hydra has tenticles to trap prey oranisms thta pass close by. Hydra does not have organs of vision, so it must employ other senses to locate prey. It has sensory cells that are sensitive to touch and can detect chemicals given off by potential prey organisms moving threw the water.

to catch prey hydra extends its tenticles, which are covered with stinging cells. The filments of the stinging cells are forcefully ejected toward the prey. Some filaments wrap around the prey, trapping it. Filaments os stinging cells also have tips that look like barbed harpoons, wich pierce the prey and discharge a poison that paralyzes or kills it.
once the prey is captured the hydra uses its tenticles to draw the prey to its mouth and push the prey though.

Digestion in hydra begins hallow, watter filled gastrovascular cavity, which extends into the tenticles. Lining the cavity the enzymes begin breaking food into smaller bits. the process is na example of extra cellular digestion...
 
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