Human Growth and Development Final Exam Answers

Correct Answer: B

Rationale: Brain weight increases tenfold from the twentieth week until birth. This rapid growth and development of the brain during the prenatal period is crucial for setting the foundation for future cognitive and neurological functions. Choices A, C, and D are incorrect because although they also undergo changes during prenatal development, none of them increase tenfold from the twentieth week until birth, unlike brain weight.

Correct Answer: D

Rationale: In this scenario, the researchers randomly assigned adolescents to either a single-grade classroom or a mixed-age classroom, which is an example of a field experiment. A field experiment involves manipulating independent variables in a natural setting to observe the effects on participants. This design allows for more control over variables compared to naturalistic observation, case studies, or natural experiments. Naturalistic observation involves observing subjects in their natural environment without manipulating any variables. A case study focuses on in-depth analysis of a single individual or a small group. A natural experiment involves observing naturally occurring events without intervention or manipulation by the researcher.

Correct Answer: C

Rationale: The best-known effect of smoking during the prenatal period is low birth weight. Smoking during pregnancy is a known teratogen that can lead to negative outcomes for the developing fetus, such as growth restrictions resulting in low birth weight. This condition can have significant long-term consequences on the child's health and development. Choices A, B, and D are incorrect as they are not the primary effect associated with smoking during the prenatal period. Colic is typically associated with digestive issues, respiratory distress at birth can be caused by various factors other than smoking, and delayed language development is not directly linked to smoking during pregnancy.

Correct Answer: A

Rationale: Naturalistic observation reflects the participants' everyday lives because it involves observing individuals in their natural environments without any manipulation. This allows researchers to see how people behave in real-world settings and can provide valuable insights into their typical behavior patterns. Choice B is incorrect because naturalistic observation focuses on observing behavior in its natural setting rather than comparing responses between participants. Choice C is incorrect as naturalistic observation tends to provide rich, qualitative data rather than a large amount of information in a short time. Choice D is incorrect because in naturalistic observation, participants are observed as they naturally behave, which may not always lead to an equal opportunity for all participants to display the behavior of interest.

Correct Answer: D

Rationale: Cross-sectional studies can be threatened by cohort effects because different age groups may have experienced different historical or social contexts, influencing the results. This disparity can lead to invalid comparisons between age groups, confounding the study's findings. Option A, practice effects, refer to changes in participants' behavior due to repeated testing, not a specific threat to cross-sectional studies. Participant dropout (Option B) is a threat related to attrition in longitudinal studies, not cross-sectional studies. Sequential timing (Option C) does not pose a threat to cross-sectional studies; instead, it refers to the order of tasks in a study design.