tube foot
Quick Summary
Tube feet are small, flexible, tubular structures found in most echinoderms, such as sea urchins and starfishes. These are extensions of the animal's water-vascular system, an internal hydraulic network that uses water to facilitate movement.12
Tube feet serve various functions, including locomotion, grasping, feeding, and sensory perception. In sea urchins, they extend from pores in the test (internal skeleton) and are often tipped with suckers, aiding in movement across the ocean floor. In starfishes, hundreds of tube feet on each arm work together to propel the animal, with suckered feet also used to pry open shellfish. The structure and function of tube feet can vary significantly among different echinoderm species, adapting to their specific environments and lifestyles.234
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circulatory systemEchinodermataā¦sac (or ampulla) and a tube foot (podium), which commonly has a flattened tip that can act as a sucker. Contraction of the sac results in a valve in the lateral canal closing as the contained fluid is forced into the podium, which elongates. On contact with the substratum, theā¦
Read Moreā¦sac (or ampulla) and a tube foot (podium), which commonly has a flattened tip that can act as a sucker. Contraction of the sac results in a valve in the lateral canal closing as the contained fluid is forced into the podium, which elongates. On contact with the substratum, theā¦
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echinodermFood and feeding habitsā¦produced by soft appendages, called tube feet, contained in grooves on the tentacles, or arms. The arms are spread into a characteristic āfanā at right angles to the prevailing current, and small prey animals are passed to the mouth along the grooves by activity of the cilia and the tubeā¦
Read Moreā¦produced by soft appendages, called tube feet, contained in grooves on the tentacles, or arms. The arms are spread into a characteristic āfanā at right angles to the prevailing current, and small prey animals are passed to the mouth along the grooves by activity of the cilia and the tubeā¦
Read More- echinodermWater-vascular system
Tube feet have been implicated in photoreception and chemoreception; the eyespots in the terminal tentacles of asteroids are the most conspicuous photoreceptors.
Read MoreTube feet have been implicated in photoreception and chemoreception; the eyespots in the terminal tentacles of asteroids are the most conspicuous photoreceptors.
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