Deck 3: Evolutionary Theories of Longevity and Aging

Question 1

Fisher's reproductive value indicates that fitness is greatest during youth.He noted that the peak of the reproductive value,or ______,seemed to coincide with the ??????______ rate of mortality.
(a)mortality;lowest
(b)fecundity;highest
(c)fitness;lowest
(d)death rate;highest

Answer 1

C

Question 2

Most likely without recognizing his finding,Medawar established the foundations for the theory that aging arises as a stochastic process resulting from ______,whereas longevity evolved from ______,as a by-product from genes important to survival to reproductive age.
(a)the forces of enthalpy;natural selection
(b)thermodynamic forces;natural selection
(c)the forces of natural selection;enthalpy
(d)the forces of enthalpy;thermodynamic

Answer 2

B

Question 3

Age-structure analysis includes measures of survival and ______ in order to evaluate reproductive rates and the age at which fitness is greatest.

Answer 3

fecundity

Question 4

Hamilton hypothesized that any population,even a stable population,could fluctuate in size at different ages,depending on age-specific mortality.______ was more likely to reflect reproductive potential at specific ages than the total integrative value over the life span.
(a)Longevity
(b)Breeding season
(c)Natural selection
(d)Fitness

Question 5

True or false: The grandmother hypothesis posits that care given by grandmothers to children in early societies allowed their daughters to have more children and,thus,to increase overall fitness.

Question 6

Genetic determinism implies that all genes are selected for:
(a)survival of the species.
(b)a particular purpose and only for that purpose.
(c)the greatest fitness.
(d)reproductive value.

Question 7

Population genetics is the science that focuses on the rate of growth and mortality characteristics of a population.

Question 8

True or false: The force of natural selection increases with age.

Question 9

The foundation of mutation accumulation lies in the observation that a trade-off exists between ______ and ______.
(a)natural selection;mortality
(b)reproduction;mortality
(c)aging;natural selection
(d)fitness;mortality

Question 10

The rate of aging in a population or an individual that is caused by environmental hazards is known as:
(a)intrinsic rate of aging.
(b)the theory of mutation accumulation.
(c)extrinsic rate of aging.
(d)reproductive value.

Question 11

The intrinsic rate of natural increase,r,is affected by birth and death rates.

Question 12

True or false: Hamilton's force of natural selection on mortality declines after the start of reproduction.

Question 13

Fisher was the first to suggest that solving for ______ provides a measure of fitness for an individual in a population.
(a)r,the intrinsic rate of natural increase,
(b)l_x,survivorship at time x,
(c)m_x,fecundity at time x,
(d)d_x,population size at time x,

Question 14

the logistic equation \DELTAN = rN[(K \minus N)/K]),what does the variable r represent?
(a)population size
(b)carrying capacity of the population
(c)life expectancy
(d)intrinsic rate of natural increase

Question 15

Weismann proved that ______ cells alone transfer the chemicals of inheritance to the next generation.
(a)somatic
(b)germ
(c)progenitor
(d)stem

Question 16

True or false: Medawar used the example of Huntington's chorea to suggest that senescence closely reflected the fixation of a single gene.

Question 17

Hamilton's mathematical theory on longevity was a monumental breakthrough in the understanding of how ______,not aging,evolved.
(a)fitness
(b)breeding season
(c)longevity
(d)natural selection

Question 18

______ is a process in which genes can be fixed in a small population as a result of the random sorting of alleles at the time of meiosis.
(a)Genetic drift
(b)Mutation accumulation
(c)Fitness
(d)Intrinsic rate of aging

Question 19

trade-off hypothesis suggests that:
(a)mortality comes at the cost of reproduction.
(b)fitness comes at the cost of mortality.
(c)selection occurs at the level of the group.
(d)successful reproduction comes at the cost of mortality.

Question 20

termed by Weismann,______ traits are classified as physical problems of aging that occur after reproduction and are neutral to the forces of natural selection.
(a)adaptive
(b)inherited
(c)nonadaptive
(d)non-phenotypical

Question 21

Choose the term that fits the following definition: A laboratory method that models natural selection,in which eggs or offspring are collected from short-lived,rapidly reproducing species that have a particular trait.The process continues for several generations until the trait has become dominant in the population.
(a)artificial selection
(b)genetic drift
(c)mutation accumulation
(d)laboratory selection

Question 22

True or false: The age at which reproduction begins to wane does not affect longevity.
Testing Evolutionary Models of Longevity

Question 23

True or false: Artificial selection experiments in Drosophila supported Fisher's and Hamilton's mathematical predictions.

Question 24

True or false: Both the intrinsic and extrinsic rates of mortality are linked to the timing of reproduction,which,in turn,affects longevity.

Question 25

Evolutionary theory predicts that organisms subjected to high predation will reproduce ______ and have ______ offspring than organisms reared in a stable population with low predation.
(a)late;fewer
(b)early;more
(c)late;more
(d)early;fewer

Question 26

The disposable soma theory is based on the evolutionary principle that all environments have ______ resources and organisms compete for those resources.
(a)infinite
(b)finite
(c)unlimited
(d)multiple

Question 27

True or false: All experiments in wild populations agree with those conducted in the laboratory that organisms living in areas of high predation have significantly shortened longevity.

Question 28

True or false: The disposable soma theory suggests a trade-off between the soma and germ cells.

Question 29

Short-answer question: Briefly describe a laboratory experiment that evaluates whether the trade-off between reproduction and life span results from extrinsic factors.
Evolution and Aging

Question 30

Fill in the blank: Williams's theory of antagonistic pleiotropy suggests that the trade-off between benefit and detriment of a pleiotropic gene will always favor the ______,if it occurs at the right time in the reproductive life span.

Question 31

The disposable soma theory suggests that reproductively successful early metazoans allocated their available resources to:
(a)mitochondria of somatic cells.
(b)DNA repair mechanisms in germ cells.
(c)DNA repair mechanisms in somatic cells.
(d)mitochondria of germ cells.

Question 32

Antagonistic pleiotropy predicts that genes conveying a benefit for fitness early in life will be selected even if they are ______ late in life.
(a)advantageous
(b)drifting
(c)nonexistent
(d)disadvantageous

Question 33

Williams combined the general concepts of ______ with Medawar's ______ to suggest a mechanism by which senescence can arise in a population in which genes are selected for reproductive success.
(a)aging;declining force of natural selection
(b)fecundity;disposable soma theory
(c)pleiotropy;declining force of natural selection
(d)natural selection;disposable soma theory

Question 34

Circle the correct answer: The finding that a gene linked to long life also produces deformed eggs is an example of the disposable soma theory / antagonistic pleiotropy.

Question 35

The disposable soma theory has it basis in what tenet of evolutionary theory?
(a)localization
(b)survival
(c)optimality
(d)fitness