SCIENCE
ZOOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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pulsing their bell
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crawling with tentacles
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complex muscular limbs
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They are sessile.
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Detailed explanation-1: -The medusa is a free-swimming form; it moves by rhythmic muscular contractions of the bell, providing a slow propulsive action against the water. The other principal body type of the adult cnidarian is the polyp, a stalked, sessile (attached) form.
Detailed explanation-2: -planula, plural planulae, free-swimming or crawling larval type common in many species of the phylum Cnidaria (e.g., jellyfish, corals, and sea anemones). The planula body is more or less cylindrical or egg-shaped and bears numerous cilia (tiny hairlike projections), which are used for locomotion.
Detailed explanation-3: -The medusa form is generally small and short-lived. Its primary function is to carry out sexual reproduction and to allow the species to disperse to different locations. Hydrozoa are classified based on the presence of a membrane called the velum that lines the inside edge of the bell in the medusa forms.
Detailed explanation-4: -They contract their hollow, saucer-shaped bodies (called bells) to force water out, which propels them forward.