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Body Structure |
Digestion |
Reproduction |
Nervous System and Oxygen Transport |
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Single Opening – mouth |
Both sexual and asexual.
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- Lacks brain and spinal cord
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Shape: cylindrical |
Food enters the gastrovascular cavity. |
Asexually by budding |
Mesoglea contains nerve cells to distribute messages throughout the body. |
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Cell Layer: (2)
Endoderm- inner layer
Ectoderm: outer layer
Mesoglea: lies between the two layers. |
Digestion begins with the release of specialized enzymes.
Phagocytosis: the process by which food particles are ingested by endoderm cells. |
Sexually- Sexual organs are produced, Gonads: testes and ovaries.
Fertilization occurs when sperm swims to ovaries of another hydra.
Zygote develops attached to the wall of the parent and forms a gastrula that then drops from the parent . |
Tentacles are another form of sensory organs. |
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Basal disk: Means for attaching to surfaces. |
Food is distributed throughout the body. |
Hydra emerges from its protective coat in the spring. |
Lacks a special transport system.
Diffusion is the process by which oxygen moves in, and carbon dioxide moves out. |
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Tentacles : means for trapping food organisms. |
Food is excreted through the mouth .
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- Diffusion is also the hydra’s means for intercellular circulation.
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