According to the U

question 42

Multiple Choice

According to the U.S. Census Bureau, in 2005, what percentage of the population was over the age of 65?

• A) 50%
• B) 25%
• C) 30%
• D) 12%
• E) it could not be determined

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Definitions:

Monozygotic Twins

Identical twins; these siblings result from one zygote splitting in two, so they share the same genes.

Genetically Identical

Describes organisms, such as twins or clones, that have exactly the same DNA sequence.

Plasticity

The brain's ability to change and adapt as a result of experience, learning, or injury.

Epigenetics

The study of changes in organisms caused by modification of gene expression rather than alteration of the genetic code itself.