Possible Evidence That Life Once Existed on Mars Has Been

question 18

Multiple Choice

Possible evidence that life once existed on Mars has been discovered.The evidence

• A)Was discovered in a meteorite that originated on Mars
• B)Was discovered in samples of Mars returned to Earth by a spacecraft
• C)Was seen in images of the surface of Mars taken by Global Surveyor
• D)Consisted of chlorophyll lines found in spectra of Mars

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Definitions:

Hormones

Biological molecules produced by glands that regulate bodily functions and behavior by traveling through the bloodstream to target organs.

Neurons

Nerve cells that transmit information throughout the body and brain, serving as the building blocks of the nervous system.

Reticular Formation

A structure in the brainstem that plays a crucial role in arousal and attention and that screens sensory messages entering the brain.

Cerebellum

A part of the brain located at the back of the skull, primarily responsible for coordinating voluntary movements and maintaining balance and posture.