What Is Released by Axon Terminals into the Synaptic Cleft

question 53

Multiple Choice

What is released by axon terminals into the synaptic cleft to stimulate a muscle to contract?

• A) potassium ions
• B) actin
• C) sodium ions
• D) acetylcholine
• E) myosin heads

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Definitions:

Noncoding DNA

Segments of DNA that do not code for proteins but have roles in regulating gene expression and maintaining chromosome structure, among other functions.

Junk DNA

Refers to regions of DNA that are noncoding, once thought to have no function but now understood to have regulatory roles.

Genetic Markers

Specific sequences of DNA that can be used to identify individuals or species and to track inherited diseases.

DNA Segments

Sections of DNA that carry genetic information, crucial for heredity and the functioning of organisms.