In View of the Present Surface and Atmospheric Conditions on Mars

question 263

Multiple Choice

In view of the present surface and atmospheric conditions on Mars, why would there be no liquid water on its surface?

• A) The water would all be frozen, given the prevailing day and night temperatures.
• B) The very low atmospheric pressure would allow the water to boil and evaporate rapidly.
• C) Water would have reacted chemically with the surface rocks.
• D) The UV radiation from the Sun would have dissociated the water molecules into hydrogen (which would leave the planet) and oxygen (which is still present).

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Definitions:

Conditioned Response

A learned reaction or response to a previously neutral stimulus that has become conditioned through association with a stimulus that elicits an automatic response.

Unconditioned Stimulus

In classical conditioning, a stimulus that naturally and automatically triggers an unconditioned response without any prior learning.

Conditioned Stimulus

A stimulus that was once neutral but, after being paired with the unconditioned stimulus, gradually induces a conditioned response.

Aplysia

A genus of sea slugs that are often used in neurological research due to their simple, large nerve cells.