Cnidarians Have a Gastrovascular Cavity Rather Than a Complete Gut;

question 11

Multiple Choice

Cnidarians have a gastrovascular cavity rather than a complete gut; in what way(s) would this arrangement be less functional in comparison to a complete digestive system like that in the rotifer?

• A) A blind-ended cavity increases the probability of parasite attachment within the cavity.
• B) Gastrovascular digestion is less efficient because the more powerful digestive chemicals seen in advanced animals, like stomach acids, would be destructive with this type of organization.
• C) Lacking a mouth and the capacity for chewing greatly reduces the potential prey items available for cnidarians in comparison to other animals.
• D) Because undigestible materials must pass out through the same opening used to enter the cavity, a single item must be completely digested and expelled before digestion of a new food item can begin.

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Definitions:

Alienation

The feeling of being isolated and disconnected from one’s social surroundings or from one's own work or products of work.

Co-optation

A strategy by which a group incorporates individuals from another, often oppositional group, to reduce threats or to gain their perspectives, sometimes diluting the original group's goals.

Coercion

The practice of forcing another party to act in an involuntary manner by use of threats, intimidation, or some other form of pressure or force.

Negotiation

The process by which parties with differing interests and objectives discuss an issue in an attempt to reach a mutually acceptable agreement.