The Size Distribution of Exons Coding for Collagen Helical Domains

question 3

Multiple Choice

The size distribution of exons coding for collagen helical domains in various vertebrates reveals a unique pattern. This pattern provides clues to the evolutionary history of the genes encoding fibrillar collagen α chains. What is this pattern?

• A) The length of most exons is a multiple of 100 nucleotides.
• B) Most exons code for 54, or a multiple of 54, Gly-X-Y repeats.
• C) The length of most exons is a multiple of 30 nucleotides.
• D) Most exons code for 6, or a multiple of 6, Gly-X-Y repeats.
• E) None of the above.

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Definitions:

Reticular Layer

The deeper layer of the dermis, composed of dense irregular connective tissue containing collagen and elastin fibers.

Hypodermis

The deepest layer of the skin, consisting of fat and connective tissues that insulate the body and protect underlying muscles and other structures.

Dermal Papilla

A small, nipple-like extension of the dermis into the hair follicle, containing capillaries that nourish the hair.

Spinothalamic Tracts

Neural pathways in the spinal cord that transmit pain and temperature sensations to the brain.