Quantum Numbers: If the Principal Quantum Number of an Electron

question 48

Multiple Choice

Quantum numbers: If the principal quantum number of an electron is n = 5, which one of the following is NOT an allowed magnetic quantum number m_l for the electron?

• A) 0
• B) 2
• C) 3
• D) 4
• E) 5

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Definitions:

Postnatal Brain Growth

The process of brain development and increase in size that occurs after birth through childhood and adolescence.

Synapses

Connections among neurons, usually between the dendrite of one neuron and the axon of another neuron, or between the dendrites of one neuron and the cell body of a second neuron. At the synapse there is a gap between neurons, which can be bridged by chemicals called neurotransmitters.

Myelination

The phenomenon in which glial cells wrap themselves around the axons of neurons, providing an insulating sheath that facilitates the conduction of electrical impulses.

Methylation

An epigenetic change that makes the expression of a gene less likely. It involves the addition of a methyl group (an organic molecule) to DNA, either to the coded gene or to regulatory DNA. Or, it can involve the addition of a methyl group to histones that bind with DNA.