Review Sheet for Biology 203, Exam 2

Sample multiple choice questions:

Conception, etc.

1. In the morula stage, the cells are
  1. specialized for different organ functions
  2. separated into three somewhat specialized layers
  3. entirely undifferentiated (CORRECT)
  4. divided into two areas, an inner cell mass and an outer ring
2. Functions of the placenta include all of the following except
  1. diffusion of carbon dioxide out of the fetus' blood
  2. secretion of hormones to maintain the pregnancy
  3. digestion of food materials for the fetus (CORRECT ANSWER)
  4. diffusion of oxygen into the fetus' blood
3. After sperm spend seven hours in the female reproductive tract, they become able to liquefy the protective layer enclosing the ovum so that fertilization can occur. The process by which this happens is
a. lubrication b. resolution c. implantation D. capacitation
4. A blastocyst is the postconception stage of development that implants in the uterine lining.
A. true b. false
5. The protective layer that surrounds the ovum after ovulation until just before immplantation is the
a. blastocyst b. trophoblast c. placenta D. zona pellucida
6. The ________________ is the inner membrane of the two that enclose the fetus.
a. chorion b. placenta C. amnion d. trophoblast
8. The fluid that surrounds the fetus before birth is called
A. amniotic fluid b. blood c. chorionic fluid d. mucus
9. The genetic abnormality discussed in class which is characterized by incomplete reproductive development, abnormalities of the face, neck, heart, arms, and chest and learning disabilities, is due to the _______ combination of sex chromosomes.
A. XO b. XXY c. OY d. XXX
11. The later in embryonic development separation of monozygotic twins into two individuals occurs, the more likely they are to share membranes, the placenta, or other tissues.
A. true b. false
13. An extra X chromosome in a female results in a "superfemale", with exaggerated secondary sexual characteristics and increased fertility.
a. true B. false
14. Down's syndrome results from a genetic abnormality in which there is
A. an extra copy of chromosome 21 c. loss of chromosome 5
b. an extra set of 23 chromosomes d. loss of one gene on chromosome 14
15. Exposure to potentially damaging environmental agents in the third through eighth weeks after conception usually results either in death of the embryo or in no harm to it, but rarely in structural or functional defects.
a. true B. false
16. Dizygotic twins develop because
a. one egg was fertilized by sperm from two fathers
b. two eggs were fertilized, but fused before implantation
C. two eggs were separately fertilized by different sperm
d. one egg was fertilized by one sperm, but at some point separated into two embryos
17. Genetic diseases such as spina bifida and phenylketonuria (PKU) occur because of a/an ______________ deficiency.
A. enzyme b. hormone c. vitamin d. immune system
18. The normal number of chromosomes in body cells is 46; the chromosome number in the gametes (egg or sperm) is
a. 22 B. 23 c. 44 d. 12
19. The embryonic cells that will give rise to the skin, skin-derived structures, and nervous system as development progresses are in the
A. ectoderm b. mesoderm c. endoderm
20. A damaging environmental agent is most likely to cause physiological defects and minor morphological abnormalities
a. between the 2nd and the 8th week after fertilization
b. in the first 2 weeks after fertilization
C. after the 7th week after fertilization
d. after the 36th week after fertilization
21. After the 36th week of pregnancy, only the central nervous system, the eyes, and the external genitalia remain sensitive to the action of a potentially damaging substance.
A. true b. false
22. Infectious diseases which may be harmful to the fetus or newborn infant include all of the following except
a. toxoplasmosis b. syphilis C. alcoholism d. rubella

Human Sexual Response:

1. Unless the woman gives some special signal, there is not necessarily any physiological evidence that her sexual partner can use to determine whether she has had an orgasm.
A. true b. false
2. Older men may experience a longer ____________________ than younger men.
a. plateau period b. orgasmic period c. excitement period D. refractory period
3. The basic physiological process that is occurring when a tissue becomes engorged with blood during a sexual response is
a. myotonia b. orgasm C. vasocongestion d. erection
4. Darkening of the labia minora and maximal engorgement of the testes occur during
a. excitement phase b. orgasmic phase C. plateau phase d. resolution phase
5. Contractions of the muscles of the back, arms, legs, and buttocks may occur during the
a. excitement phase B. orgasmic phase c. plateau phase d. resolution phase
6. Zilbergeld and Ellison extended Masters and Johnson's phases of sexual response by adding phases that deal with their subjects' feelings as well as measuring their physiological changes.
A. true b. false
7. Contraction of the pubococcygeus muscle and elevation of the cervix and uterus are the result of
A. myotonia b. orgasm c. vasocongestion d. fertilization
8. According to a hypothesis suggested by Freud, women who experience orgasm as a result of _______________ stimulation are less mature than women who achieve orgasm as a result of other kinds of stimulation. Subsequent research has disproven this hypothesis.
a. vaginal B. clitoral c. mental d. uterine
9. The first sign of the excitement phase in women is usually
a. rapid breathing B. vaginal lubrication c. nipple erection d. flushing of the skin
10. ___________________ refers to the accumulation of tension in many muscles of the body.
a. erection B. myotonia c. vasocongestion d. lubrication
11. Vaginal lubrication occurs because
  1. muscles in the vaginal wall contract
  2. a gland near the cervix ejaculates
  3. engorged tissues near the vagina press on its walls (CORRECT)
  4. fluid accumulated in the uterus leaks out

Reproductive Dysfunction (short answer for review--questions on your test will be multiple choice)

  1. Why do many couples who visit a fertility specialist achieve a pregnancy before treatment begins?
  2. Give several examples of common causes of infertility in women and in men. How can each one be diagnosed, and how can it be treated?
  3. For what sort of infertility problems would a couple choose each of the following methods of artificial conception? artifical insemination, in vitro fertilization, gamete intrafallopian transfer
  4. Describe the process of in vitro fertilization. Why is the woman given HCG and progesterone?
  5. How do the success rates for artifical methods of conception compare to the natural success rates for couples age 20-25? age 35-40?

Assisted Reproductive Technologies

7. In in vitro fertilization, the point of measuring luteinizing hormone (LH) levels every 3 hours is to make sure ovulation has occurred, so that the egg can be collected from the Fallopian tube.
a. true B. false
10. A woman whose Fallopian tubes are blocked by scarring might be able to use in vitro fertilization as a successful means of becoming pregnant.
A. true b. false
12. In in vitro fertilization, at the time the "pre-embryo" is inserted into the woman's uterus, it is at the _________ stage.
a. blastocyst b. morula C. 8-cell d. 1-cell