Please Use the Following Information to Answer the Question(s) Below

question 13

Multiple Choice

Please use the following information to answer the question(s) below.
Gene S controls the sharpness of spines in a type of cactus. Cactuses with the dominant allele, S, have sharp spines, whereas homozygous recessive ss cactuses have dull spines. At the same time, a second gene, N, determines whether or not cactuses have spines. Homozygous recessive nn cactuses have no spines at all.
-If doubly heterozygous SsNn cactuses were allowed to self-pollinate, the F2 would segregate in which of the following ratios?

• A) 3 sharp-spined:1 spineless
• B) 1 sharp-spined:2 dull-spined:1 spineless
• C) 1 sharp-spined:1 dull-spined:1 spineless
• D) 1 sharp-spined:1 dull-spined
• E) 9 sharp-spined:3 dull-spined:4 spineless

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Definitions:

Population Attributable Risk

The proportion of disease cases in the entire population that can be attributed to a particular risk factor.

Exposure

The state of being subjected to some effect or influence, often used in context of exposure to diseases, chemicals, or other risk factors.

Coronary Heart Disease

A disease characterized by the narrowing or blockage of the coronary arteries, usually due to atherosclerosis, leading to reduced blood flow to the heart muscle.

Epidemiologists

Experts who study the distribution and determinants of health-related states or events in specified populations, and the application of this study to control health problems.