In the eighth month of pregnancy, what typically happens?

Correct Answer: D

Rationale: In the eighth month of pregnancy, lanugo typically is shed. Lanugo is the fine, downy hair that covers a fetus's body to help regulate body temperature while in the womb. By the eighth month, many fetuses shed this hair as they prepare for birth. Choices A, B, and C are incorrect because fetal growth doubling, neuron production increasing, and the formation of eyes, ears, nose, jaw, and neck occur in earlier stages of pregnancy, not specifically in the eighth month.

Correct Answer: A

Rationale: The correct answer is A: 'It is linked to impulsivity and overactivity.' Prenatal marijuana exposure has been associated with impulsivity and overactivity in children based on research findings. However, lasting consequences of prenatal marijuana exposure are not as well-established compared to other teratogens. Choice B is incorrect because lasting consequences are not firmly established. Choice C is incorrect because studies have shown negative effects of prenatal marijuana exposure. Choice D is incorrect as prenatal marijuana exposure is not primarily linked to physical malformations.

Correct Answer: A

Rationale: Recent evidence suggests that paternal alcohol use around the time of conception can alter gene expression. This means that paternal alcohol consumption can potentially impact the genes and genetic materials passed on to offspring, affecting their development and health. Choice B is incorrect because fetal alcohol syndrome is typically associated with maternal alcohol consumption during pregnancy, not paternal alcohol use around conception. Choice C is incorrect as there is no direct link between paternal alcohol use and blood vessel abnormalities. Choice D is incorrect as paternal alcohol use can indeed have negative effects on the developing organism, particularly through altering gene expression.

Correct Answer: C

Rationale: High levels of prenatal lead exposure are related to low birth weight and brain damage. Lead exposure during pregnancy can have harmful effects on the developing fetus, leading to complications such as decreased birth weight and potential long-term brain damage. Choices A, B, and D are incorrect because they do not directly correlate with the known effects of prenatal lead exposure. While lead exposure can indeed cause a variety of health issues, such as heart defects and urinary tract problems, the primary concerns related to prenatal exposure are low birth weight and brain damage.

Correct Answer: D

Rationale: In healthy, physically fit women, regular moderate to vigorous exercise during pregnancy is related to improved fetal cardiovascular functioning. Regular exercise has been shown to benefit both the mother and baby by promoting better cardiovascular health and overall well-being during pregnancy. Choices A, B, and C are incorrect as exercise during pregnancy, when done appropriately, does not lead to lower birth weight, higher risk of premature birth, suppressed immune system development, or serious damage to the central nervous system. Instead, it is known to have positive effects on fetal development and maternal health.