Question 1

Which statement is true about free-radical damage?

Accepted Answer

Free-radical damage is caused by unstable molecules that can damage cells, proteins, and DNA. This damage can contribute to various diseases and conditions associated with aging. As we age, our cells become less efficient at repairing this damage, leading to an increase in free-radical damage.

Question 2

As the lens of the eye stiffens and thickens with age, __________.

Accepted Answer

As the lens of the eye stiffens and thickens with age, the ability to focus on close objects declines, which is known as presbyopia. This is a very common vision problem that affects most people as they age.

Question 3

According to the cross-linkage theory of aging, bonds between protein fibers in connective tissue can lead to __________.

Accepted Answer

The cross-linkage theory of aging suggests that bonds between protein fibers in connective tissue can cause the loss of flexibility in the skin and clogging of arteries. This can lead to age-related conditions such as wrinkles and cardiovascular disease. Choices A, C, and D do not accurately reflect the effects of cross-linking on the body.

Question 4

Doyle wants to protect the health of his endocrine system. The safest approach for Doyle is __________.

Accepted Answer

The safest approach for protecting the health of the endocrine system is a combination of a healthy diet and regular physical activity. This helps to maintain a healthy weight and balances hormone levels naturally, without the potential risks and side effects of hormone therapy or genetic reconstruction. Increasing body fat can actually harm the endocrine system by leading to a higher risk of obesity and associated health problems.

Question 5

Almeda's skin has lost some flexibility and the lens of her left eye is beginning to cloud. She is concerned that the normally separate protein fibers that make up her body's connective tissue are forming bonds with one another. You can tell Almeda that she can reduce cross-linking by __________.

Accepted Answer

Eating a healthy diet can help reduce cross-linking in the body's connective tissue. In particular, consuming foods high in antioxidants such as fruits and vegetables has been shown to decrease the formation of cross-links. Other lifestyle factors such as reducing exposure to UV radiation and avoiding smoking can also help. Decreasing heart rate, increasing body fat, and moving less often are not effective ways to reduce cross-linking.

Question 6

The physical changes of the adult years are __________.

Accepted Answer

The physical changes of adult years are multidimensional, meaning they occur in multiple aspects of our biological functioning such as sensory, muscular, and cardiovascular systems. They are also multidirectional, meaning some aspects of our functioning may decline while others may improve or remain stable. The changes are not universal in all members of our species, as they can vary based on genetics, lifestyle factors, and environmental factors. Additionally, the changes do not occur in a stagelike, predictable sequence, as individuals can experience different physical changes at different times and rates.

Question 7

Decreased vigor of the immune response seems to be __________.

Accepted Answer

Decreased vigor of the immune response is genetically programmed but intensified by other aging processes such as thymic involution and accumulation of memory T-cells, which leads to a decrease in naive T-cells.

Question 8

Senescence __________.

Accepted Answer

Senescence refers to the declining years of an organism as it reaches the end of its life span. It begins once body structures reach maximum capacity and efficiency, and is characterized by a decline in physiological function and an increase in the incidence of age-related diseases. Senescence is a natural process that occurs in all living organisms, and is thought to be an inevitable consequence of the passage of time.

Question 9

One hypothesized cause of age-related DNA and cellular abnormalities is the __________.

Accepted Answer

Free radicals are molecules that have unpaired electrons and are highly reactive. They can damage cells and DNA, leading to aging and related abnormalities.

Answer: A
 Telomeres are the protective caps at the ends of chromosomes, and they tend to shorten with age. This can lead to DNA damage and cellular abnormalities.

Answer: B
 Androgens are male sex hormones, and their production tends to decrease with age. While this can contribute to some age-related changes, it is not a hypothesized cause of DNA and cellular abnormalities.

Answer: D
 While an increase in synapses may have some impact on brain function and aging, it is not a hypothesized cause of DNA and cellular abnormalities.

Question 10

Telomeres __________.

Accepted Answer

Telomeres are repetitive sequences of DNA that protect the ends of chromosomes from degradation during replication. As cells divide and age, telomeres naturally shorten, eventually leading to cell death or senescence. Shortened telomeres have also been linked to a range of age-related diseases such as cancer, cardiovascular disease, and neurodegeneration.

Question 11

Lorenzo quit smoking and reduced his alcohol intake. At the same time, he improved his healthy eating behaviors and increased his physical activity. Lorenzo's lifestyle changes are likely to __________.

Accepted Answer

Telomerase is an enzyme that adds DNA repeats to the end of chromosomes (telomeres), which can slow down telomere shortening. Therefore, an increase in telomerase activity is likely to slow down the shortening of telomeres, promoting longevity. This can happen when one adopts a healthier lifestyle, including quitting smoking, reducing alcohol intake, healthy eating, and physical activity. Therefore, Lorenzo's lifestyle changes are likely to increase telomerase activity.

Question 12

The __________ theory of aging receives some support from kinship studies indicating that longevity is a family trait.

Accepted Answer

The genetically programmed theory of aging suggests that longevity is determined by genetic factors and receives support from studies showing that longevity tends to run in families. This theory suggests that biological changes that occur with aging, such as declines in the immune system and hormone production, are genetically determined and programmed to occur at a specific time.

Question 13

Telomere shortening predicts __________.

Accepted Answer

Telomere shortening is a natural process that occurs as cells divide, and it is correlated with aging. As telomeres shorten, cells become more susceptible to damage and death. Telomere length has been found to be a predictor of mortality, with individuals who have shorter telomeres having a higher risk of earlier death.

Question 14

An enzyme called telomerase __________.

Accepted Answer

Telomerase is an enzyme that can lengthen telomeres, which are the protective ends of chromosomes that shorten with each cell division. By adding DNA to the telomeres, telomerase can effectively extend the lifespan of cells, potentially preventing cellular aging and senescence.

Question 15

In some species, __________ is/are associated with longer life.

Accepted Answer

The answer of In some species, __________ is/are associated with...

Question 16

According to the "random events" theory of biological aging, __________.

Accepted Answer

The "random events" theory of biological aging suggests that DNA in body cells is gradually damaged through mutations, leading to aging. This theory focuses on the accumulation of genetic damage over time as a primary cause of aging.

Question 17

Age-related declines in hearing __________.

Accepted Answer

Age-related declines in hearing are indeed more rapid for men than for women, with studies showing that men experience these declines at a rate more than twice as fast as women. This difference is attributed to various factors including occupational noise exposure, lifestyle choices, and biological differences.

Question 18

Nora's grandfather lived to be 87, and her father is still alive at the age of 98. Nora concludes that longevity is inherited and anticipates a very long life. Nora should know that __________.

Accepted Answer

While genetics do play a role in the likelihood of living a long life, there are also other factors at play such as lifestyle, environment, and chance events. Therefore, Nora should not assume that she will automatically live a long life just based on her family history. Additionally, while there may be some genetic risk and protective factors at play, it is unlikely that longevity is directly inherited like eye color or height.

Question 19

According to the "random events" theory, as spontaneous or externally caused mutations accumulate, __________.

Accepted Answer

According to the "random events" theory, as mutations accumulate, there is a greater likelihood of abnormal or cancerous cells being produced. This is because mutations can alter the normal functioning of genes involved in cell growth and division, leading to uncontrolled cell proliferation and potentially the development of tumors.

Question 20

The strongest evidence for __________ comes from research showing that human cells allowed to divide in the laboratory have a lifespan of 50 divisions, plus or minus 10.

Accepted Answer

This evidence supports the existence of "aging genes" as cells reaching their replicative limit is a key feature of cellular senescence, which is under genetic control. The other options (B, C, D) are not supported by this particular evidence.

Quiz 13: Physical and Cognitive Development in Early Adulthood