Consider the Following Description of an Area of Current Research

question 23

Multiple Choice

Consider the following description of an area of current research. "Beta-polypeptides are polymers of beta amino acids with backbones one carbon longer than alpha-polypetptides. Like the alpha-polypeptides found in nature, beta-polypeptides can form stable helices and pleated sheets." Which levels of protein structure are cited in this statement?

• A) primary
• B) secondary
• C) tertiary
• D) quaternary
• E) primary and secondary
• F) primary, secondary, and tertiary
• G) primary, secondary, tertiary, and quaternary

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Definitions:

Neurotransmitter

Chemical substances released by neurons to transmit signals across a synapse to another neuron, a muscle cell, or some other kind of cell.

Sympathetic Nervous System

Part of the autonomic nervous system that activates the body's rapid involuntary response to dangerous or stressful situations.

Parasympathetic Nervous System

Part of the autonomic nervous system responsible for conserving energy and promoting relaxation and recovery processes in the body.

Action Potential

A rapid increase and subsequent decrease in voltage or electrical charge across a cellular membrane, leading to nerve signal transmission.