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Biology for AP® Courses

Critical Thinking Questions

Biology for AP® CoursesCritical Thinking Questions
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43 .
(credit: modification of work by Lutz Becks/ResearchGate)

A species of microscoping animals (Brachionus calyciflorus) can reproduce both sexually and asexually. A research study compared how sexually-reproduced offspring and asexually reproduced offspring fared under different conditions and produced the given graphs.

Make a claım about these graphs.

  1. The left graph shows the population under a shortage of resources. The right graph shows the population growing with abundant resources.
  2. The left graph shows the fitness of the sexually-reproduced offspring. The right graph shows the fitness of the asexually-reproduced offspring.
  3. The left graph shows the population living in their native environment. The right graph shows the population adapting to a new environment.
  4. The left graph shows a population that is steadily growing. The right graph shows a population that is declining.
44 .
Why is sexual reproduction useful when only half the individuals reproduce and two cells must combine to form a new cell?
  1. It completes in a very short period of time.
  2. It results in the rapid production of many offspring.
  3. It increases genetic diversity, allowing organisms to survive in an unpredictable environment.
  4. It requires less energy and leads to genetic variation in the offspring.
45 .
Sex determination in humans and other mammals is dictated by the presence of sex chromosomes. Are there different factors that determine the sex of other types of animals?
  1. No, the sex of an individual is only determined by the presence of sex chromosomes.
  2. Yes, temperature also determines the sex of an individual.
  3. Yes, humidity and temperature determine the sex of an individual.
  4. Yes, pH and humidity determine the sex of an individual.
46 .
What are some advantages of internal compared with external fertilization?
  1. Internal fertilization leads to more genetic variations and increases the survival rates of offsprings.
  2. Internal fertilization increases the survival rates of offspring, and large numbers of offspring are produced.
  3. Internal fertilization increases the survival rates of offspring, and the chance of fertilization with a specific partner also increases.
  4. Internal fertilization increases the survival rates of offspring and decreases the chance of fertilization with a specific partner.
47 .
(credit: modification of work by Planet Ocean)

The image shows a sea turtle.

What can be said about the these turtles based on this image?

  1. They are oviparous.
  2. They are ovoviviparous.
  3. They are viviparous.
  4. They do external fertilization.
48 .
Compare the specialization of reproductive structures found in different types of land animals.
  1. In birds, an opening called the cloaca is used to transfer sperm, whereas in mammals, the presence of the penis and vagina allows direct delivery. Complete reproductive systems are formed in insects, with eggs maturing in the testes and sperm maturing in the ovaries.
  2. In birds, an opening called the cloaca is used to transfer sperm, whereas in mammals, the presence of the penis and vagina allows direct delivery. Complete reproductive systems are formed in insects, with eggs maturing in the ovaries and sperm maturing in the testes.
  3. In birds, sperm are transferred via the spermatheca, whereas in mammals, the presence of the penis and vagina allows direct delivery. Complete reproductive systems are formed in insects, with eggs maturing in the ovaries and sperm maturing in the testes.
  4. In birds, an opening called the cloaca is used to transfer sperm, whereas in mammals, the presence of the penis and vagina allows direct delivery. Insects always use parthenogenesis.
49 .
Explain the fate of the newly released secondary oocyte after ovulation.
  1. If it fuses with a sperm, the resulting zygote enters the cervix for implantation. If it is not fertilized, it will return to the oviduct.
  2. If it fuses with a sperm, the resulting zygote enters the uterus for implantation. If it is not fertilized, it will return to oviduct.
  3. If it fuses with a sperm, the resulting zygote enters the uterus for implantation. If it is not fertilized, it will degrade and exit the body.
  4. If it fuses with a sperm, the resulting zygote enters the cervix for implantation. If it is not fertilized, it will degrade and exit the body.
50 .
Explain the similarities and differences in sexual response in males and females.
  1. Both males and females show specific arousal, but the sexual response differs in intensity and duration.
  2. Both males and females show specific arousal. In males, breathing rate and heart rate are increased. In females, there is a decrease in breathing rate and heart rate.
  3. Vasodilation occurs in both males and females, allowing blood to engorge erectile tissue in the nipples, clitoris, labia, vagina, and penis. In males, breathing rate and heart rate are increased. In females, there is a decrease in breathing rate and heart rate.
  4. Both males and females show an increase in heart rate, breathing rate, and blood pressure during phase one and phase two. However, sexual response differs in intensity and duration in males and females. Also, males show specific arousal, while females show non-specific arousal.
51 .
Compare and contrast spermatogenesis and oogenesis.
  1. Both are the form of gametogenesis that takes place through mitosis. Spermatogenesis is the process of formation of four sperm in the testes in males. The process of formation of one ovum in the ovaries in females is called oogenesis.
  2. Both are the form of gametogenesis that takes place through meiosis. Spermatogenesis is the process of formation of four sperm in the testes in males. The process of formation of four ova in the ovaries in females is called oogenesis.
  3. Bothare the form of gametogenesis that takes place through meiosis. Spermatogenesis is the process of formation of four sperm in the testes in males. The process of formation of one ovum in the ovaries in females is called oogenesis.
  4. Both are the form of gametogenesis that takes place through meiosis. Spermatogenesis is the process of formation of one sperm in the testes in males, while the process of formation of one ovum in the ovaries in females is called oogenesis.
52 .
Based on your understanding of hormonal control of human reproduction, explain how the hypothalamus regulates the secretion of reproductive hormones in males.
  1. The hypothalamus releases FSH, and LH at puberty by the secretion of GnRH. FSH stimulates the Leydig cells in the testes, and LH stimulates the Sertoli cells to synthesize and secrete testosterone.
  2. The hypothalamus releases FSH, and LH at puberty by the secretion of GHRH. FSH stimulates the Sertoli cells in the testes, and LH stimulates the Leydig cells to synthesize and secrete testosterone.
  3. The hypothalamus stimulates the release of FSH, and LH at puberty by the secretion of GnRH. FSH stimulates the Sertoli cells in the testes, and LH stimulates the Leydig cells to synthesize and secrete testosterone.
  4. The hypothalamus releases TSH, and LH at puberty by the secretion of GnRH. TSH stimulates the Sertoli cells in the testes, and LH stimulates the Leydig cells to synthesize and secrete testosterone.
53 .
What are the events that take place in a non-pregnant woman after ovulation?
  1. Because a fertilized egg is not implanted into the uterus in a non-pregnant woman, the corpus luteum degenerates, and the levels of estrogen and progesterone decrease. The endometrium begins to degenerate as the progesterone level drops, initiating the next menstrual cycle.
  2. Because a fertilized egg is not implanted into the uterus in a non-pregnant woman, the corpus luteum degenerates, and the levels of estrogen and progesterone increase. The endometrium begins to degenerate as the estrogen level increases, initiating the next menstrual cycle.
  3. Because a fertilized egg is not implanted into the uterus in a non-pregnant woman, the corpus luteum degenerates and the levels of estrogen and progesterone increase. The endometrium begins to degenerate as the progesterone level rises, initiating the next menstrual cycle.
  4. Because a fertilized egg is not implanted into the uterus in a non-pregnant woman, the corpus luteum degenerates and the levels of estrogen and progesterone decrease. The myometrium begins to degenerate as the progesterone level drops, initiating the next menstrual cycle.
54 .
The side effects of menopause can be diminished by hormone replacement therapy (HRT). However, many doctors are hesitant to recommend it. What are the possible reasons for this?
  1. Its negative side effects, which include increased risk of colon cancer, osteoporosis, heart disease, macular degeneration, and possibly depression
  2. Its negative side effects, which include increased risk of stroke or heart attack, blood clots, breast cancer, ovarian cancer, endometrial cancer, gall bladder disease, and possibly depression.
  3. Its negative side effects, which include increased risk of stroke or heart attack, blood clots, breast cancer, colon cancer, endometrial cancer, gall bladder disease, and possibly dementia.
  4. Its negative side effects, which include increased risk of stroke or heart attack, blood clots, breast cancer, ovarian cancer, endometrial cancer, gall bladder disease and possibly dementia.
55 .
(credit: modification of work from University of Michigan Medical School)

The image shows early embryonic development in humans in days 1 - 7 after fertilization.

Which label shows the zygote and the blastocyst?

  1. The zygote is labels A to C. Blastocyst is label D.
  2. The zygote is label A. Blastocyst is label D.
  3. The zygote is labels A to C. Blastocyst is label E.
  4. The zygote is label A. Blastocyst is label E.
56 .
Identify the statement that accurately describes where the embryonic stem cells and germ layers originate after the blastula is formed.
  1. The inner cell mass contains embryonic stem cells, which arrange themselves into three germ layers.
  2. The trophoblast in the blastula contains embryonic stem cells, which arrange themselves into three germ layers.
  3. The inner cell mass contains embryonic stem cells, whereas the germ cells originate from the trophoblast.
  4. The embryonic stem cells and germ layers originate from the blastocoel present inside the blastula.
57 .
(credit: modification of work by Organismal Biology/Georgia Tech Biological Sciences, under CC BY-NC-SA 3.0 license)

The image shows development of the early embryo after the blastula stage.

What stage is the embryo at in the two pictures after blastula?

  1. Blastocyst.
  2. Trophoblast.
  3. Gastrula.
  4. Blastocoel.
58 .
During organogenesis, the ectoderm forms the neural cells and the epidermal cells. How do the ectoderm cells determine which type of cells to form?
  1. Growth factors signal some of the ectodermal cells to form epidermal cells, and the remaining cells form the neural plate.
  2. The notochord cells of the mesoderm signal the ectodermal cells to form epidermal cells as well as the neural plate.
  3. Growth factors signal some of the ectodermal cells to form epidermal cells, and the remaining cells form neural crest cells.
  4. Proteins involved in the Wnt signaling pathway signal the ectodermal cells to form the epidermal cells and the neural plate.
59 .
Refer to Figure 34.27
.
(credit: modification of work by Stephen J. Falchek, MD/MERCK Manual)

The image shows a condition called spina bifida. This condition occurs when the neural tube does not close properly at the lower end of the body at the spine.

What would happen if the neural tube does not properly close at the upper end of the body?

  1. There would be anomalies in the face of the embryo.
  2. The brain of the embryo would not develop properly.
  3. The heart and the lungs of the embryo would not develop.
  4. There would be anomalies in the arm development.
60 .
(credit: modification of work by Stephen J. Falchek , MD/MERCK Manual)

The image shows a condition called spina bifida. This condition occurs when the neural tube does not close properly at the lower end of the body at the spine. The bottom right condition, called meningomyelocele, is the most severe version of spina bifida. It causes severe impairment, while other versions of the condition may not cause severe impairment.

Make a claim about why meningomyelocele causes severe impairment.

  1. In meningomyelocele, the sac filled with the cerebrospinal fluid is larger.
  2. In meningomyelocele, the brain tissue is also effected.
  3. In meningomyelocele, the vertebra housing the spinal cord are weaker.
  4. In meningomyelocele, the spinal cord is not in its normal location.
61 .
Which best describes the three stages of labor?
  1. During stage one, the cervix thins. During stage two, the cervix is dilated to about 10 cm and the baby is expelled from the uterus. The last stage is the passage of the placenta after the baby has been born.
  2. During stage one, the cervix thins and is dilated to about 10 cm. During stage two, the baby is expelled from the uterus. The last stage is the passage of the placenta after the baby has been born.
  3. During stage one, the cervix thins. During stage two, the cervix is dilated to about 10 cm. During the last stage, the baby is expelled from the uterus, followed by the placenta.
  4. During stage one, the cervix thins and may or may not be dilated. During stage two, the baby is expelled from the uterus. The last stage is the passage of the placenta after the baby has been born.
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