What Is the Most Common Source of the Extra Chromosome

question 23

Multiple Choice

What is the most common source of the extra chromosome 21 in an individual with Down syndrome?

• A) nondisjunction in the mother
• B) nondisjunction in the father
• C) duplication of chromosome 21
• D) deletion in either parent

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Definitions:

Secondary

The coil in a transformer that receives energy from the primary coil through electromagnetic induction, thereby transferring energy from the primary to the load.

Laminated Construction

A manufacturing technique used in electrical machines and transformers to minimize eddy current losses by stacking thin sheets of metal together.

Thin Sheets

Flat, slender pieces of material of small thickness compared to its other dimensions.

Metal

A class of elements characterized by high electrical conductivity, luster, malleability, and which are typically solid at room temperature, except for mercury.