Describe major prenatal milestones during the second trimester of pregnancy
What will be an ideal response?
Prenatal development is sometimes divided into trimesters, or three equal time periods. The second trimester starts at the beginning of the fourth month. At the beginning of the second trimester, the external genitals are well-formed, and the sex of the fetus can be detected with ultrasound. Other finishing touches appear, such as fingernails, toenails, tooth buds, and eyelids. The heartbeat can be heard through a stethoscope.
By the middle of the second trimester, between 17 and 20 weeks, the new organism has grown large enough that the mother can feel its movements. A white, cheeselike substance called vernix protects its skin from chapping during the long months spent bathing in the amniotic fluid. White, downy hair called lanugo also appears over the entire body, helping the vernix stick to the skin.
At the end of the second trimester, many organs are well-developed. Most of the brain's billions of neurons are in place; few will be produced after this time. However, glial cells, which support and feed the neurons, continue to increase rapidly throughout the remaining months of pregnancy, as well as after birth. At the same time, neurons begin forming synapses, or connections, at a rapid pace. Brain growth means new behavioral capacities. The 20-week-old fetus can be stimulated as well as irritated by sounds. And if a doctor looks inside the uterus using fetoscopy, fetuses try to shield their eyes from the light with their hands, indicating that sight has begun to emerge. Still, a fetus born at this time cannot survive. Its lungs are immature, and the brain cannot yet control breathing and body temperature.
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Although children under age 6 sometimes confuse appearance and reality, as Piaget said, studies by Flavell and others reveal that __________.
A. children as young as 3 can make appearance-reality distinctions under certain carefully designed experimental circumstances B. children as young as 2 understand that a sponge that looks like a rock is really a sponge C. when 5-year-olds are shown a sponge that looks like a rock, they believe it is a rock even after the have felt its spongy texture D. children as young as 3 typically understand that magical beings such as Santa Claus are not really magical
Which of the following is NOT one of the factors that have been linked to the development of anorexia nervosa or bulimia nervosa in young women?
a. mothers who model unhealthy dieting behaviors for their daughters b. parents who are negligent or uninvolved in their children's lives c. the presence of rigid, all-or-none thinking and maladaptive beliefs d. a genetic vulnerability to eating disorders
Compared to students with different ethnic and SES backgrounds, most educators would predict, based on research, that students who are white and from middle- and upper-class backgrounds will do ______________________
Fill in the blank(s) with the appropriate word(s)
Which of the following did Skinner believe about the role of genetics in behavior?
a. Skinner denied the existence of innate behaviors and instead proposed that each organism learned all behaviors through their contingencies. b. Skinner believed that innate behaviors occurred only early in life and that they were outgrown through the use of differential reinforcement. c. Skinner postulated a role for innate behaviors that was secondary to the role of learned behaviors, as innate behaviors only emerge when there is brain damage. d. Skinner recognized the existence of innate behavior and that conditions selecting certain behaviors might change and make the behaviors maladaptive.