What Is the Cause of Down Syndrome

question 92

Multiple Choice

What is the cause of Down syndrome?

• A) an extra chromosome on the 21st pair
• B) an extra X chromosome on the 23rd pair
• C) neurotransmitter excesses
• D) neurotransmitter deficiencies

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Definitions:

Risk Factors

Conditions that increase the likelihood of a negative developmental outcome.

Low-Birth-Weight

Refers to newborns who weigh less than 2,500 grams (5 pounds, 8 ounces) at birth, a condition associated with various health risks.

Early Months

The initial period following an event, often emphasizing the beginning stages of development or adjustment, such as the first months of life or a new position.

States of Arousal

The different levels of alertness and physiological activity in an individual, ranging from deep sleep to intense excitement or alertness.