Summarize factors that account for the dramatic rise in fraternal twinning and other multiple births in industrialized nations over the past several decades
What will be an ideal response?
Answer: Currently, fraternal twins account for 1 in about every 33 births in the United States. Older maternal age, fertility drugs, and in vitro fertilization are major causes of the dramatic rise in fraternal twinning and other multiple births in industrialized nations over the past several decades—a trend that has recently leveled off with improved in vitro procedures. The rate of fraternal twinning rises with maternal age, peaking between 35 and 39 years, and then rapidly falls. Multiple births occur less often among women with poor diets, and occur more often among women who are tall and overweight or of normal weight as opposed to slight body build. Multiple births are more likely with fertility hormones and in vitro fertilization.
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Eysenck's theory focuses on the interaction of
a) biology and philosophy. b) individual differences and general human characteristics. c) personality factors and physiological characteristics. d) scientific experimentation and introspective studies.
Holly is a developmentally disabled child and is working with a therapist who is training
Holly to write her name. The training procedure consists of gripping the pencil properly, followed by simple strokes with the pencil, then by combining strokes into simple patterns that more and more closely resemble the letters in Holly's name. The therapist is careful to provide praise as Holly lengthens the sequence of responses. This procedure is referred to as a. shaping. b. unit collection. c. specialization training. d. response partitioning. e. response gradation.