Use the Following to Answer Questions

question 74

Multiple Choice

Use the following to answer questions:
The diagram below shows experiments performed to determine whether the fates of cells are irrevocably determined.
-If cell fate were not irrevocably determined, and skin tissue could develop into notochord tissue but not into brain tissue, a normal embryo would develop in

• A) Experiment 1 only.
• B) Experiment 2 only.
• C) Experiment 3 only.
• D) Experiments 1 and 2.
• E) Experiments 2 and 3.

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Definitions:

Neurotransmitters

Chemical messengers that transmit signals across the synaptic gap from one neuron to another in the nervous system.

Synaptic Gap

The tiny space between neurons where neurotransmitters are released to transmit information.

Molecules

The smallest unit of a chemical compound that can exist, consisting of two or more atoms held together by chemical bonds.

Refractory Period

A period immediately following an action (e.g., a neuron's firing or human ejaculation) during which a second action is difficult or impossible to initiate.