Some Large, Multicellular, Aquatic Animals Have No Circulatory System

question 58

Multiple Choice

Some large, multicellular, aquatic animals have no circulatory system. They manage gas exchange

• A) by bringing the external environment (with its supply of oxygen) inside their body.
• B) by means of endosymbiotic bacteria that produce oxygen inside their tissues.
• C) solely by diffusion from outside their bodies.
• D) by basking at the surface periodically to allow for diffusion of oxygen.
• E) None of the above

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Definitions:

Attentively Listen

The act of actively and fully concentrating on a speaker, comprehending their message, and responding thoughtfully.

Proxemics

The study of human use of space and the effects that population density has on behaviour, communication, and social interaction.

Demonstration

A method of teaching by example rather than simple explanation, showing how a task should be performed.