Question 24.1

How does a quantitative characteristic differ from a discontinuous characteristic?

Question 24.2

Briefly explain why the relation between genotype and phenotype is frequently complex for quantitative characteristics.

Question 24.3

Why do polygenic characteristics have many phenotypes?

Question 24.4

Explain the relation between a population and a sample. What characteristics should a sample have to be representative of the population?

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Question 24.5

What information do the mean and variance provide about a distribution?

Question 24.6

How is the standard deviation related to the variance?

Question 24.7

What information does the correlation coefficient provide about the association between two variables?

Question 24.8

What is regression? How is it used?

Question 24.9

List all the components that contribute to the phenotypic variance and define each component.

Question 24.10

How do broad-sense and narrow-sense heritabilities differ?

Question 24.11

Briefly outline some of the ways in which heritability can be calculated.

Question 24.12

Briefly describe common misunderstandings or misapplications of the concept of heritability.

Question 24.13

Briefly explain how genes affecting a polygenic characteristic are located with the use of QTL mapping.

Question 24.14

How is the response to selection related to narrow-sense heritability and the selection differential? What information does the response to selection provide?

Question 24.15

Why does the response to selection often level off after many generations of selection?