Gene S Controls the Sharpness of Spines in a Type

question 44

Multiple Choice

Gene S controls the sharpness of spines in a type of cactus. Cacti with the dominant allele, S, have sharp spines, whereas homozygous recessive ss cacti have dull spines. At the same time, a second gene, N, determines whether or not cacti have spines. Homozygous recessive nn cacti have no spines at all. The relationship between genes S and N is an example of which of the following inheritance patterns?

• A) incomplete dominance
• B) epistasis
• C) pleiotropy
• D) codominance

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Definitions:

Normal Good

A good for which demand increases when consumer income rises, and falls when consumer income decreases, all other factors being equal.

Student Income

The amount of money earned or received by students from employment, grants, stipends, or other sources while pursuing their studies.

Demand RISE

An increase in the quantity of a product or service that consumers are willing and able to purchase at a given price.

Demand Curve

A graphical representation showing the relationship between the price of a good and the quantity of that good consumers are willing to purchase at various prices.