Deck 4: Theories of Senescence and Aging

Question 1

In this chapter's Senior View, Martha Russell expresses strong disagreement with any theories that claim

A) you can put off senescence
B) everyone gets sick when they get old
C) most people know very little about senescence
D) our fates are controlled by chance

Answer 1

B

Question 2

Which of the following animals show very little senescence even when kept in captivity?

A) turtles
B) cats
C) canaries
D) catfish

Answer 2

A

Question 3

The Hayflick number is the

A) average number of cells per tissue sample for a given species
B) maximum number of cell divisions for cells of a given species
C) minimum number of cell divisions for cells of a given species
D) average cell weight for cells of a given species

Answer 3

B

Question 4

The Hayflick number for human cells is

A) about 25
B) about 50
C) about 75
D) unlimited

Question 5

The initial length of telomere stand for members of a species is

A) always the same
B) dependent upon season of birth
C) dependent upon climate
D) determined genetically

Question 6

One line of evidence against telomere length being responsible for senescence is that

A) telomere length doesn't change with age
B) senescent tissue often has long telomere strands
C) telomere length cannot be measured
D) cells don't immediately die when they stop dividing

Question 7

A major difference between cancer cells and normal cells is that

A) cancer cells replace telomeres lost during cell division
B) normal cells do not divide when neighboring cells occupy that space
C) normal cells have an upper limit on cell division
D) all of the above

Question 8

One version of the evolution theory of senescence claims that

A) we are programmed to decline and die after reaching adulthood
B) natural selection determines the life span of a species
C) only the healthiest individuals will live beyond middle-age
D) we are meant to only live long enough to reproduce

Question 9

Antagonistic pleiotropy refers to the theory that genes that increase longevity also

A) increase senescence
B) decrease the probability of reproduction
C) increase the probability of reproduction
D) cause cancer in old age

Question 10

Free radicals result from

A) consuming antioxidants
B) advanced senescence
C) sunlight and radiation
D) too much R and R

Question 11

High levels of DHEA have been associated with

A) lower risk of cardiovascular disease in older men
B) lower risk of cardiovascular disease for men and women
C) higher risk of cardiovascular disease in women
D) higher risk of cardiovascular disease for men and women

Question 12

Free radicals are

A) highly reactive molecules
B) scavenger viruses
C) serious infections
D) a group of radical seniors

Question 13

Our bodies have a natural built in protection against the actions of free radicals. This protection is referred to as

A) DHEA
B) SOD
C) Vitamin C
D) Anti-oxidants

Question 14

Mice given anti-oxidants with their food can live 30% longer than mice given a normal diet. Such results

A) are excellent support for free radical theory
B) are difficult to interpret because the long lived mice also eat less
C) provide good evidence for garbage accumulation theories of senescence
D) argue against garbage accumulation theories of senescence

Question 15

Which of the following is not an antioxidant?

A) Vitamin B
B) Vitamin C
C) Vitamin E
D) Beta-carotene

Question 16

Which of the following hormones has been found to increase muscle mass when given to older men but also led to swollen ankles and stiff joints?

A) melatonin
B) telomerase
C) DHEA
D) Human growth hormone

Question 17

Which of the following hormones is a regulator of biological rhythms?

A) melatonin
B) telomerase
C) DHEA
D) Human growth hormone

Question 18

A problem for wear and tear theory is that

A) it is not scientific
B) body parts with the most wear seem to last longer
C) tears in human tissue are quickly healed
D) all of the above

Question 19

DNA damage/repair theory claims that senescence is due to cells reading less of the DNA strand as they grow older. This is thought to occur because

A) the DNA strand has been damaged by environmental factors
B) DNA repair units may grow more efficient with age
C) Older cells can not easily decode DNA strands
D) Old cells read only about 30% of a DNA strand

Question 20

DNA damage might be caused by

A) the actions of free radicals
B) sunlight
C) pollutants in the air
D) all of the above

Question 21

Garbage accumulation theories claim that waste products build up as we grow older and cause senescence. Which of the following is one of these accumulating waste products?

A) SOD
B) Free radicals
C) Collagen
D) Lipofuscin

Question 22

A major difference between programmed and unprogrammed theories of senescence is that programmed theories

A) attribute senescence to environmental factors
B) claim that senescence follows a predetermined plan
C) rely on computer models to predict senescence in a given species
D) all of the above

Question 23

Describe three theories, which attempt to explain senescence and the evidence for and against each one.

Question 24

What general evidence is used to support biological theories of senescence. Why is this general evidence not regarded as strong?

Question 25

Describe the difference between programmed and unprogrammed theories of senescence. Describe in detail one theory of each category.

Question 26

Compare and contrast some of the theories presented in this chapter.

Question 27

Describe possible connections among some of the theories of senescence presented in this chapter.