Down Syndrome Is Characterized By

question 38

Multiple Choice

Down syndrome is characterized by:

• A) single base mutations
• B) the presence of 47 chromosomes per somatic cell
• C) increasing risk with younger maternal age
• D) the presence of an extra chromosome 18 in each somatic cell
• E) the same symptoms observed in each individual

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Definitions:

Myelin

A fatty substance that forms a sheath around the axons of many neurons, helping to speed the conduction of nerve impulses.

Synaptic Vesicles

Membrane-bound sacs in the axon terminal of neurons that store neurotransmitters to be released at the synapse.

Synapse

The junction between two neurons where electrical or chemical signals are transmitted from one neuron to another.

Neurotransmitter

A Neurotransmitter is a chemical substance released by nerve cells to transmit signals to other nerve cells across synapses, playing a crucial role in the functioning of the nervous system.