Choose the One Alternative That Best Completes the Statement or Answers

question 53

Multiple Choice

Choose the one alternative that best completes the statement or answers the question.
-A fossilized leaf contains 18% of its normal amount of carbon 14. How old is the fossil (to the nearest year) ? Use 5600 years as the half-life of carbon 14.

• A) 35,538
• B) 1,600
• C) 13,829
• D) 23,309

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Definitions:

Axon Terminal

The end of an axon, which makes synaptic connections with another nerve cell or with a muscle or gland cell, allowing for the transmission of electric nerve impulses.

Neurotransmitter

Chemical substances released at the end of a nerve fiber by the arrival of a nerve impulse, which by diffusing across the synapse or junction causes the transfer of the impulse to another nerve fiber, a muscle fiber, or some other structure.

T-tubule

Tubular extensions of the cell membrane in muscle cells, which play a critical role in the conduction of electrical signals for muscle contraction.

Action Potential

A short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, allowing nerve cells to communicate.