Human Growth and Development Exam 1

Correct Answer: A

Rationale: In a correlational design, researchers gather information on individuals without altering their experiences. Correlational studies examine the relationship between two or more variables without any manipulation or control by the researchers. The researchers simply observe and measure the variables of interest without intervening in any way. Choices B, C, and D are incorrect because they describe aspects related to experimental designs rather than correlational designs. In an experimental design, researchers manipulate variables, assign participants to different treatment conditions, and control changes in the independent variable, which is not the case in correlational studies.

Correct Answer: B

Rationale: By using random assignment of participants to treatment conditions, investigators increase the chances that participants' characteristics will be equally distributed across treatment groups. Random assignment helps reduce the likelihood of bias in the selection process and ensures that any differences between groups are due to the treatment and not pre-existing group differences. Sequential, systematic, and correlational assignment methods do not provide the same level of assurance in distributing participants' characteristics equally across treatment groups.

Correct Answer: C

Rationale: The correct answer is C: Dilation and effacement of the cervix. This stage can last for hours, especially for first-time mothers, as the cervix needs to dilate and efface to allow for the baby's passage through the birth canal. Once the cervix is fully dilated and effaced, the woman can begin pushing during the second stage of labor to deliver the baby. The delivery of the baby itself is usually a shorter process compared to the time taken for the cervix to dilate and efface. Choices A, B, and D are incorrect because they represent other stages within the labor process that come after the dilation and effacement of the cervix.

Correct Answer: C

Rationale: Anoxia during labor and delivery can cause cerebral palsy. Cerebral palsy is a group of disorders that affect a person's ability to move and maintain balance and posture. It is caused by damage to the developing brain, often due to a lack of oxygen during labor and delivery. Spina bifida (Choice A) is a neural tube defect that occurs during embryonic development and is not directly caused by anoxia during labor. Anencephaly (Choice B) is a severe neural tube defect where the baby is born without parts of the brain and skull, not typically caused by anoxia during labor. Muscular dystrophy (Choice D) is a genetic disorder characterized by progressive muscle weakness and is not directly related to anoxia during labor and delivery.

Correct Answer: D

Rationale: The placenta delivers food and oxygen to the developing organism during pregnancy. It is a temporary organ that forms in the first trimester of pregnancy. Choice A is incorrect as the placenta forms in the first trimester, not the second trimester. Choice B is incorrect as the amniotic sac, not the placenta, encloses the developing organism in amniotic fluid. Choice C is incorrect as the placenta contains blood vessels (arteries and veins) that deliver nutrients to the embryo, not just one large vein.