Chapter 2

Define genotype and phenotype. Which one has the most influence on the intrinsic rate of aging? Which has the most influence on the extrinsic rate of aging?

What are some of the factors that make identification of a biomarker for human aging challenging?

Consider the following experimental design for a study on how aging might affect hearing. Subjects in three age groups, 20–49,50–69, and 70–90 years, will be exposed to different levels of sound, and their ability to hear the sounds will be compared. Is this an example of a cross-sectional or longitudinal design? Explain how the cohort effect and selective mortality will affect the results and conclusions.

Explain why a biomarker for human aging may require the use of personal genomics. How will personal genomics be used to improve the health of the aging population?

What are the three factors that make interspecies comparisons of mortality rates difficult when using the Gompertz model?

Which is considered a good measure of the extrinsic rate of human aging: mean or maximum life span? Why?

How does the observation that the mortality rate of a population decelerates in late life support the concept of selective mortality?