The Gaia Theory Says That

question 41

Multiple Choice

The Gaia Theory says that

• A)the biosphere contains a diversity of habitats and niches favorable to life because living things have made it that way.
• B)the complementary actions of respiration and photosynthesis have maintained a relatively stable atmospheric pool of carbon dioxide and oxygen.
• C)all living things must obtain nutrients and energy from their environment.
• D)all elements have their origin in a nonliving, long-term reservoir.
• E)ecosystems are open with regard to energy because the sun is constantly renewing them with a renewable source.

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Definitions:

Olfactory Bulb

Ganglion-like enlargement at the rostral end of the olfactory tract that lies over the cribriform plate; receives the olfactory nerves from the nasal cavity.

Olfactory Tract

Nerve tract that projects from the olfactory bulb to the olfactory cortex.

Transmembranous Receptor

Proteins spanning across the membrane of cells that receive chemical signals from outside the cell and initiate a response within the cell.

Odorant

A substance that is capable of producing a smell, often detected by the olfactory system.