Different Ratios Occur in Crosses with Single Gene Pairs or Two

question 37

Multiple Choice

Different ratios occur in crosses with single gene pairs or two gene pairs. What types of ratios are likely to occur in crosses dealing with a single gene pair?

• A) 3:1, 1:1, 1:2:1
• B) 9:7, 12:3:1
• C) 1:1:1:1, 1:4:6:4:1
• D) 9:3:3:1, 1:2:1
• E) 15:1, 1:2

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Definitions:

Brachial Plexus

A network of nerve fibers running from the spine, through the neck, and into the arm, responsible for sensory and motor functions.

Vagus

A cranial nerve that is responsible for various functions including heart rate, digestion, and regulation of several physiological processes.

Obturator

Refers to structures, such as the obturator foramen or muscles, covering or closing an opening, specifically in the pelvis.

Phrenic

Pertaining to the diaphragm, such as the phrenic nerve which controls the diaphragm muscle, thus playing a vital role in the breathing process.