Below Is a Genetic Map for Three Loci $\begin{array} { lll } \text { A } &&&&\text { B } &&&\text { C } \\\hline\end{array}$

question 20

Essay

Below is a genetic map for three loci. Which two of these loci would show the smallest physical distance in base pairs, if the frequency of crossing over is equal in this chromosome region? Explain your answer. $\begin{array} { lll } \text { A } &&&&\text { B } &&&\text { C } \\\hline\end{array}$
$5 \text { map units } ~~~~~~~~~7 \text { map units }$

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Definitions:

Tympanic Membrane

The thin layer separating the outer ear from the middle ear, which vibrates in response to sound waves.

Surgical Repair

A medical procedure aimed at restoring the function or appearance of a part of the body.

Bony Labyrinth

A complex system of channels and cavities within the temporal bone of the skull, important for hearing and balance.

Membranous Labyrinth

A complex system of membrane-covered tubes and chambers within the inner ear, responsible for hearing and balance.