AP Biology : Reproductive System

Study concepts, example questions & explanations for AP Biology

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Example Questions

Example Question #1344 : Ap Biology

Which part of the developing blastocyst becomes the placenta in mammals?

Possible Answers:

Yolk

Embryoblast

Blastocoel

Trophoblast

Correct answer:

Trophoblast

Explanation:

The trophoblast is a layer of cells that surround the blastocyst. The trophoblast becomes the outer layer of the placenta and further differentiates into syncytiotrophoblast and cytotrophoblast cells that contribute to placentation.

Example Question #151 : Reproductive System

Which of the following choices connects the developing fetus to the maternal placenta?

Possible Answers:

Endometrial villi

Umbilical cord

Amniotic sac

Fetal villi

Correct answer:

Umbilical cord

Explanation:

During fetal development, the umbilical cord is a structure that connects the fetus to the maternal placenta. The umbilical cord contains umbilical arteries and the umbilical vein, allowing oxygen, nutrient, and waste exchange between the mother and fetus. It develops from the yolk sac and allantois in the fifth week of development and is clamped or cut following childbirth.

Example Question #152 : Reproductive System

Which of the following is not true regarding Braxton Hicks contractions?

Possible Answers:

They are uterine contractions 

They signify the beginning of labor

They occur throughout pregnancy

They prepare the mother for childbirth

Correct answer:

They signify the beginning of labor

Explanation:

Braxton Hicks contractions are mild and irregular uterine contractions that are believed to prepare the mother for childbirth. The contractions may begin during the first trimester, but are often only noticed during the second and third trimesters of pregnancy.

Example Question #1347 : Ap Biology

Which of the following muscles contra to help deliver the baby during labor?

Possible Answers:

Uterine

Fallopian

Cervical

Vaginal

Correct answer:

Uterine

Explanation:

During labor, uterine contractions help dilate the cervix and descend the baby into the birth canal. As labor progresses, contractions become regular and occur more frequently. As the contractions continue to bear down on the fetus, the labor process is aided by maternal pushing.

Example Question #72 : Understanding Other Reproductive Physiology

Which of the following best describes the direct effect of uterine contractions during labor?

Possible Answers:

Neither fetal descent nor cervical dilation

Fetal descent

Cervical dilation

Both cervical dilation and fetal descent

Correct answer:

Both cervical dilation and fetal descent

Explanation:

Uterine contractions during labor help the fetus descend into the birth canal and aid cervical dilation.

Example Question #153 : Reproductive System

Which of the following best describes what occurs physiologically when a woman’s “water breaks”? 

Possible Answers:

Rupture of the amniotic sac

Detachment of the umbilical cord

Descent of the baby into the birth canal

Expulsion of the placenta

Correct answer:

Rupture of the amniotic sac

Explanation:

The rupture of the amniotic sac during birth is commonly said to be when a woman’s “water breaks.” This typically occurs at the beginning of labor, but sometimes has to be ruptured by a medical professional. The rupture decreases cushioning of the fetus and increases pressure of the contractions, aiding the descent of the fetus into the birth canal.

Example Question #1350 : Ap Biology

Which of the following best describes when a pregnancy is considered to be “full term”?

Possible Answers:

30 to 31 weeks

37 to 38 weeks

39 to 41 weeks

33 to 35 weeks

Correct answer:

39 to 41 weeks

Explanation:

A woman is said to be “full term” when she is at 39 to 41 weeks of pregnancy. Medical intervention to induce labor during this time is not ideal.

Example Question #154 : Reproductive System

Which of the following is a complication associated with pregnancy?

Possible Answers:

All of these

Ectopic pregnancy

Preeclampsia

Postpartum depression

Anemia

Correct answer:

All of these

Explanation:

Pregnancy related medical conditions and complications are incredibly common due to strain on the mother and extreme biological changes associated with pregnancy. Examples include postpartum depression, anemia, preeclampsia, and ectopic pregnancy.

Example Question #155 : Reproductive System

Which of the following best describe methods that are used to prevent premature births?

Possible Answers:

Nutritional supplements

All of these

Reducing the mother's activity

Screening for complications

Avoiding stress

Correct answer:

All of these

Explanation:

Premature birth is the leading cause of death in newborns. While the exact causes of premature birth are not completely understood, certain methods may work to prevent it. These methods include nutritional supplements, avoiding stress, screening for complications, and reduction in activity.

Example Question #1353 : Ap Biology

Which of the following must occur in order to deliver the shoulders of the fetus?

Possible Answers:

The mother needs to stop pushing

None of these

Release of the placenta

Fetal rotation in the birth canal

Breech of the fetus

Correct answer:

Fetal rotation in the birth canal

Explanation:

In order to deliver the fetal shoulders, the fetus needs to rotate in the birth canal.

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