In a Disease That Is Associated with a Single Recessive

question 19

Multiple Choice

In a disease that is associated with a single recessive allele, the concordance among dizygotic twins should be .

• A) 0%
• B) 25%
• C) 50%
• D) 75%
• E) 100%

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Definitions:

Spina Bifida

A congenital condition in which the backbone and the spinal cord's protective layers do not fully encase the spinal cord.

Genetic Map

A graphical representation of the arrangement of genes or sequence of DNA on a chromosome, indicating the relative distances between genetic markers.

Dominant Gene

A genetic trait that is expressed in an individual's phenotype, overshadowing the effect of a recessive gene if present.

Endocytosis

A cellular process by which cells internalize molecules or particles from their surroundings through the envelopment and formation of vesicles.