SCIENCE
ZOOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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through its lungs and their gills
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through the nerve net and the gastrovascular cavity
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through its cnidocytes and their surface cells
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through the gastrovascular cavity and surface cells
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Detailed explanation-1: -The gastrovascular cavity has only one opening that serves as both a mouth and an anus (an incomplete digestive system). Like the sponges, Cnidarian cells exchange oxygen, carbon dioxide, and nitrogenous wastes by diffusion between cells in the epidermis and gastrodermis with water.
Detailed explanation-2: -In the case of cnidarians, oxygen is taken in and carbon dioxide is removed through the process of diffusion. Diffusion is when a material moves from an area of high concentration to an area of low concentration. In jellyfish, box jellies, and hydra, diffusion happens through the cells of the epidermis.
Detailed explanation-3: -Cnidarians lack organs. This means that they do not have respiratory or circulatory systems. Like the cells in sponges, the cells in cnidarians get oxygen directly from the water surrounding them.
Detailed explanation-4: -There are two basic cnidarian body shapes: a polyp form, which is attached to a surface; and an upside-down free-floating form called a medusa.
Detailed explanation-5: -Cnidarians have an incomplete digestive system with only one opening; the gastrovascular cavity serves as both a mouth and an anus.