Echinoderms

question 23

Multiple Choice

Echinoderms

• A)are clearly related to cnidarians because of their radial symmetry.
• B)may have evolved from a sessile ancestor.
• C)probably evolved from pterobranch hemichordates.
• D)do not show relationships to any other group of animals.

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Definitions:

Parenchyma

A type of plant tissue composed of living cells that are often spacious and used for functions such as photosynthesis, storage, and tissue repair.

Ground Tissue

A type of plant tissue that fills the interior of a plant, consisting of parenchyma, collenchyma, and sclerenchyma cells, and is responsible for photosynthesis, storage, and support.

Phloem

The vascular tissue in plants responsible for the transport of organic nutrients, particularly sugar, from the leaves to other parts of the plant.

Dissolved Sugars

Sugars that have been dissolved in a liquid, thereby becoming part of the liquid's solution.