What do telomeres and telomerase have to do with cellular theories of aging?
What will be an ideal response?
Some theories of aging propose that the number of times cells can divide is directly related to the length of life span of an organism. The tips of chromosomes, called telomeres, help regulate cell division. Evidence suggests that telomeres adjust a cell's response to stress and growth stimulation based upon cell divisions and DNA damage. The enzyme, telomerase, is needed in DNA replication to fully reproduce telomeres when cells divide .But telomerase is usually not present in somatic cells when they divide. The result is that with each cell division, the telomeres become shorter .Eventually, chromosomes can't replicate because the telomeres have become too short.
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Sanderson and Alderson argue that recent empirical studies designed to test Sahlins's "original affluent society" thesis
a. cast serious doubt on it b. perhaps qualify it, but do not overturn it c. prove that prehistoric hunter-gatherers lived in a kind of society that can be described as a true paradise d. are methodologically sound, but theoretically flawed
The distinction between prejudice and discrimination is that
a. prejudice is a behavior, and discrimination is an attitude. b. prejudice is an attitude, and discrimination is a behavior. c. prejudice is an ideology, and discrimination is an attitude. d. prejudice is an attitude, and discrimination is an ideology.
Lucinda established the validity of her religiosity measure by making sure it corresponded with our common agreements and our individual mental images concerning her concept. She did this by checking with other people, particularly those familiar with religious issues. Which measure of validity did she use?
a. face validity b. criterion-related validity c. construct validity d. split-half validity e. divergent validity
What are the two primary physical changes that occur during the sexual response cycle?
- Plateau and transudation - Excitement and resolution - Myotonia and orgasm - Vasocongestion and myotonia