OESOPHAGUS STOMACH
ECHINODERMS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Float on the surface of the water with their holdfasts suspended in the water column
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Produce bad-tasting or toxic chemical to deter the sea urchin from eating it
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Produce blades that are several meters in length to maximize its photosynthetic capabilites
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Attach their holdfasts into sandy sediment to hide them from the grazers
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Detailed explanation-1: -Purple sea urchins are a natural part of kelp ecosystems, but when predators that keep their numbers in check started to disappear, the urchin population boomed. In herds, urchins can consume kelp at a rate of 30 feet per month, creating urchin barrens.
Detailed explanation-2: -Those with sea urchins had less kelp. Paine experimented by removing the sea urchin, and kelp started growing. The urchins (herbivores) were keeping the kelp (producer) population down to very low levels.
Detailed explanation-3: -One possible explanation for the sudden loss of kelp forests is the outbreak of voracious sea urchin grazers. When urchin populations are uncontrolled, they overgraze kelp forests, thereby shifting forested habitats to an alternative “barren” state.
Detailed explanation-4: -Many small animals, and certain types of algae, make the kelp holdfast their home. The inside of the holdfast provides protection from predators and from strong ocean currents.