Exam 13: Aging and Other Life-History Characters
Alleles that influence more than one trait are referred to as ________.
pleiotropic
In terms of the size of offspring,data from different (a)fish families and (b)fruit fly species are represented in the accompanying figure.Evaluation of this data reveals that ________. 

E
Two theories have been proposed regarding the aging process: the rate-of-living theory and the evolutionary theory of aging.Compare and contrast these two theories.Are there any similarities? What are their differences? Which elements are supported by research,and which elements have been refuted?
The rate-of-living theory suggests that the aging process is a result of an organism's metabolism and the accumulation of damage over time. This theory proposes that organisms with higher metabolic rates will age faster and have shorter lifespans. On the other hand, the evolutionary theory of aging suggests that aging is a result of natural selection favoring genes that have beneficial effects early in life, even if they have detrimental effects later in life. This theory proposes that aging is a result of the declining force of natural selection with age.
There are some similarities between the two theories. Both theories acknowledge that aging is a complex process influenced by genetic, environmental, and physiological factors. Additionally, both theories recognize that aging is a universal phenomenon observed in most living organisms.
However, there are also significant differences between the two theories. The rate-of-living theory focuses on the physiological aspects of aging, emphasizing the role of metabolism and damage accumulation. In contrast, the evolutionary theory of aging emphasizes the role of natural selection and the trade-offs between early-life benefits and late-life costs.
Research has provided support for elements of both theories. Studies have shown that organisms with higher metabolic rates tend to have shorter lifespans, supporting the rate-of-living theory. Additionally, research has demonstrated that genetic factors and trade-offs between early-life and late-life benefits play a role in the aging process, supporting the evolutionary theory of aging.
However, there are also elements of both theories that have been refuted by research. For example, some studies have found that genetic and environmental factors can influence the rate of aging independently of metabolic rate, challenging the strict interpretation of the rate-of-living theory. Similarly, research has shown that the decline in the force of natural selection with age may not fully explain the aging process in all organisms, suggesting that the evolutionary theory of aging may not be applicable to all species.
In conclusion, while both the rate-of-living theory and the evolutionary theory of aging offer valuable insights into the aging process, they also have limitations and areas of disagreement. Further research is needed to fully understand the complex mechanisms underlying aging in different organisms.
Researchers have tested Lack's hypothesis on clutch sizes,and the results are shown in the accompanying figure.In this graph,the histogram shows actual clutch sizes over 22 years for the Great Tit (Parus major),whereas the individual data points reflect results of manipulation of clutch size.According to this data,________. 

Life-history analysis may provide us with clues to human female menopause―more specifically,the way in which your text describes it,"Why should women's reproductive systems shut down by age 50,while the rest of their organs and tissues are still in good repair?" Two hypotheses were discussed; describe,compare,and contrast them.Which one do you think is more likely,and why?
At the most fundamental of levels,differences among life histories are due to differences in the allocation of ________.
When reproductive interests between males and females of the same species differ,as in the case of fruit flies,sexual selection may actually favor adaptations arising in one sex but that are detrimental in the other sex.This,in turn,leads to subsequent "counter-measure" adaptations in the sex that are subject to harm or detriment.This kind of antagonistic sexual adaptation has been termed ________ sexual selection.
According to the data shown in the accompanying figure,the reduction in reproduction rates most closely correlates with a corresponding reduction in survival in ________. 

The conclusion,"Mutation hypothesis notes that mutations causing premature senescence are selected against weakly," makes more sense if we consider that ________.
In an "ideal" world,organisms that are fine-tuned for reproduction would ________.
Some researchers argue that short telomeres actually facilitate a longer life span in mammals.The reasoning for this argument includes the idea that ________.
The theory of aging that posits that aging is caused either by the accumulation of deleterious mutations later in life or by a trade-off between repair to damaged tissues and reproduction is called the ________.
Female sand crickets are known to produce two phenotypic variants: long-winged and short-winged.Moreover,these two variants have been shown to allocate different amounts of their energy budget to flight or ovary development,respectively.The development of female crickets into one or the other of these variants is due to ________.
Tandem repeat sequences found at the ends of chromosomes,such as TTAGGG as found in vertebrates,are known as ________.
Traits which by logic should show less genetic variation because of their close association with reproduction fall into which category?
The accompanying figure represents Lack's hypothesis on clutch size.According to this hypothetical data,________. 

The maintenance of genetic variation in sea-squirts (Botryllus scholosseri)has been studied by Richard Grosberg.Interestingly,these sea-squirts have two genetically determined life history forms.In one,called ________ the modules in a colony reproduce once and then die.In the other morph,called ________ colonies reproduce sexually at least three times before they die.
The theory of aging that posits that aging is caused by irreparable damage to the cells,tissues,and organs of an organism brought about by such things as errors in protein synthesis and the accumulation of toxic metabolites is the ________.
The hypothesis that predicts that parents will attempt to rear the number of offspring that maximizes the survival rates of offspring is known as ________.[two words]
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