The History of Mercury Can Be Summarized as

question 118

Multiple Choice

The history of Mercury can be summarized as

• A) mostly volcanic activity and crustal deformation; the only craters to survive were formed within the last billion years.
• B) thin crust forming at first, followed by extensive bombardment, the craters from which were then covered by lava flows that produced extensive lava plains between the remaining craters.
• C) early cooling to form a thick crust, with no evidence of volcanism or lava flows at any time.
• D) rapid cooling to form a thick crust during the early bombardment, with a few isolated lava flows and very dense cratering everywhere else.

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Definitions:

Brainstem

The lower extension of the brain where it connects to the spinal cord, responsible for controlling many basic life functions such as breathing and heart rate.

Spinal Cord

A long, thin, tubular structure made up of nervous tissue, extending from the brainstem down the vertebral column, playing a critical role in transmitting neural signals between the brain and the rest of the body.

Pyramids

Structures in the medulla oblongata of the brain involved in the transmission of motor signals to the spinal cord.

Descending Tracts

These are pathways in the central nervous system that transmit motor signals from the brain down the spinal cord to the muscles or glands.