Describe the theory of biological aging that emphasizes the programmed effects of specific genes
What will be an ideal response?
Answer: Genetically programmed aging proposes the existence of “aging genes” that control biological changes, such as menopause, efficiency of gross-motor skills, and deterioration of body cells. The theory receives some support from kinship studies indicating that longevity is a family trait. People whose parents had long lives tend to live longer themselves. And greater similarity exists in the lifespans of identical than fraternal twins. But the heritability of longevity is low to moderate. Rather than inheriting longevity directly, people probably inherit risk and protective factors, which influence their chances of dying earlier or later. The strongest evidence for the existence of “aging genes” comes from research showing that human cells allowed to divide in the laboratory have a lifespan of 50 divisions, plus or minus 10. With each duplication, a special type of DNA called telomeres—located at the ends of chromosomes, serving as a “cap” to protect the ends from destruction—shortens. Eventually, so little remains that the cells no longer duplicate at all. Telomere shortening acts as a brake against somatic mutations, which become more likely as cells duplicate. But an increase in the number of senescent cells (ones with short telomeres) also contributes to age-related disease, loss of function, and earlier mortality. Researchers have begun to identify health behaviors and psychological states that accelerate telomere shortening—powerful biological evidence that certain life circumstances compromise longevity.
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Dr. Ford wants to test the hypothesis that room color can affect memory. To that end, he randomly assigns 10 students to a condition where they study a written passage while seated in a room that is painted a lilac color. The other 10 students study the passage while seated in an identical room that is painted bright orange. After both groups studied the passage for one hour, they are given a
multiple-choice test over the material. Dr. Ford then calculates how many questions the students in both groups answer correctly. In Dr. Ford’s study, the independent variable is ____. a. ?the people who studied the passage while seated in the lilac room b. ?the color of the room in which the students studied the passage c. ?the test scores of the students d. ?whether or not the students were able to recall information about the passage
Describe two things that could lead to personality change in adulthood. Explain your answers, showing how the change would happen and how common it is
What will be an ideal response?
If you classically condition a baby to fall asleep whenever a lullaby is played on the crib music box, the lullaby serves as the
a) conditioned stimulus (CS). b) conditioned response (CR). c) unconditioned stimulus (UCS). d) unconditioned response (UCR).
How are the body senses similar to those of the auditory system?
A. Most of the neurons from one side of the body project to the hemisphere of the same side. B. Most of the neurons from one side of the body cross over and project to the hemisphere of the opposite side. C. All of the neurons pass through the hypothalamus before projecting to the primary sensory areas of the brain. D. All of the neurons from one side of the body cross over and project to the hemisphere of the opposite side.