Which of the Following Is a Definition of the Isoelectric

question 72

Multiple Choice

Which of the following is a definition of the isoelectric point of an amino acid?

• A) The pH at which an amino acid has no net charge
• B) The pH at which the α-NH₂ group is completely protonated
• C) The melting point of an amino acid
• D) The conductivity of a 1 M solution of an amino acid in water

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Definitions:

Channelrhodopsin-2 (ChR2)

A light-sensitive protein derived from algae used in optogenetics to control the activity of neurons with light.

Halorhodopsin (NpHR)

A light-activated chloride pump used in optogenetics to inhibit neuronal activity by hyperpolarizing neurons when exposed to light.

Depolarize

To reduce the polarization of a neuron, making the inside of the cell less negative compared to the outside, and promoting the generation of an action potential.

Electrical Stimulation

The use of electrical impulses to stimulate nerves or muscle fibers to improve function, relieve pain, or promote healing.