Exam 46: Animal Reproduction

On a submarine expedition to the ocean bottom, you discover a population of fish that are only female. What type of reproduction does this fish most likely use?

You decide to study two species of birds, both of which form monogamous pairs (one male and one female). In species 1, you find that the eggs in a pair's nest are in fact almost always the offspring of that pair. In species 2, you are surprised to find that many of the eggs in a nest were actually fathered by males of neighboring pairs. Apparently, mating outside of monogamous pairings is widespread in species 2. What would you expect to observe if you examined the reproductive tracts of the female birds in the species?

Sexual reproduction ________.

Increasing the temperature of the human scrotum by 2°C (that is, near the normal body core temperature)and holding it there would most likely ________.

In an animal that switches between sexual and asexual reproduction, when is sexual reproduction more likely to occur?

In correct chronological order, the three phases of the human uterine cycle are ________.

In close comparisons, external fertilization often yields more offspring than does internal fertilization. However, internal fertilization typically offers the advantage that ________.

Peaks of LH and FSH production occur during

A pregnant woman comes into the hospital past her due date. The doctor decides it is time for the baby to be delivered. Before performing a cesarean section, the doctor wants to try to induce labor. Which of the following would she most likely inject?

At the time of fertilization, the maturation of the human oogonium has resulted in ________.

Which of the following characterizes parthenogenesis?

Genetic mutations in asexually reproducing organisms lead to more evolutionary changes than do genetic mutations in sexually reproducing ones because ________.

Egg laying in fruit flies can be triggered (induced)when males deposit their sperm in the spermathecae of the females. What is the selective advantage of induced egg laying for the male flies?

A physician finds that a nine-year-old male patient is entering puberty much earlier than usual. Such a condition is most likely the result of a tumor in the ________.

Which of the following organisms reproduces by fission?

Use the following information to answer the question. Estrogens found in the environment have raised concerns about effects on reproductive health of animals. Researchers studied the effects that estrogens in the water have on sexual differentiation in zebrafish. They exposed embryo-larval (0-21 days post-hatching), juvenile (21-42 days post-hatching), and adult (over 200 days post-hatching)fish to three concentrations of 17β-estradiol (5, 25, and 100 nanograms/liter)that are within the range of concentrations found in water leaving sewage treatment plants in different countries. They then examined the proportion of males and females when the fish exposed at embryo-larval and juvenile stages reached adulthood. Embryo-larval stage fish that had been exposed to 100 ng/l 17β-estradiol resulted in adult populations that had substantially more females than males compared to control groups. Embryo-larval fish that had been exposed to 5 and 25 ng/l of 17β-estradiol did not show a statistically significant shift in the proportion of females. (Brion, F., C. R. Tyler, X. Palazzi, B. Laillet, J. M. Porcher, J. Garric, and P. Flammarion. 2004. Impacts of 17β-estradiol, including environmentally relevant concentrations, on reproduction after exposure during embryo-larval-, juvenile-, and adult-life stages in zebrafish (Danio rerio). Aquatic Toxicology 68:193-217.) You are assigned to write the report to the Environmental Protection Agency that needs to decide what level of 17β-estradiol to permit in sewage output. You do not want to make the level any lower than necessary, because it requires substantial additional money for the extra treatment of sewage. Given the data presented, what concentration of 17β-estradiol would you suggest is safe to prevent feminization of fish?

Refer to the following figure, which diagrams the reproductive anatomy of the human male, to answer the question. In the figure, which letter points to the vas deferens?

The surgical removal of the seminal vesicles would likely ________.

Use the following information to answer the question. For your internship at the local zoo, you have been assigned to help with the new orangutan-breeding program. Little is known about orangutan reproductive hormones, but hormone feedback cycles are often the same in closely related animals. You have been asked to use your knowledge of the interactions of human reproductive hormones to recommend injections to promote ovulation in a female orangutan when a visiting male arrives for a brief breeding visit. Which of the following hormones would you use if you want to induce ovulation right away?

Usₑ thₑ fₒllₒwᵢng ᵢnfₒᵣmₐtᵢₒn tₒ ₐnswₑᵣ thₑ qᵤₑstᵢₒn. For your internship at the local zoo, you have been assigned to help with the new orangutan-breeding program. Little is known about orangutan reproductive hormones, but hormone feedback cycles are often the same in closely related animals. You have been asked to use your knowledge of the interactions of human reproductive hormones to recommend injections to promote ovulation in a female orangutan when a visiting male arrives for a brief breeding visit. Which of the following hormones would you use if you want to induce ovulation in a few days?