Study Questions for Quiz 3 PSB 4731 Summer 2012 1 What do home pregnancy tests test for The presence of hCG 2 What are 3 things that can produce a false negative on a pregnancy test Testing is too early urine is too dilute or if directions are not followed accurately 3 What are 3 ways to predict the time of ovulation 1 If a woman has a regular 28 day cycle subtract 14 days for the luteal phase from 28 Ovulation would occur 14 days after the beginning of the previous menstruation 2 Temperature cycle more accurate Take temperature in the morning before getting out of bed Temp dips on day of ovulation rises the next day remains high during whole luteal phase 3 LH surge tests called ovulation tests Ovulation occurs two days after the surge in LH Sex during those two days is likely to lead to pregnancy 4 Briefly describe the pattern of temperature changes across the menstrual cycle Temperature dips on the day of ovulation rises the next day and remains high during the whole luteal phase 5 What are 3 possible causes of inactive or deformed sperm Undescended testicles sex chromosome anomalies infections that block the reproductive tract environmental toxins chemotherapy or heating 6 Describe the basic procedures of in vitro fertilization Women are given hormones to produce a batch of follicles then just before ovulation an ultrasound probe is inserted into the vagina to image the mature ovarian follicles Then a needle is inserted into each follicle in turn and the oocyte is removed by suction After removal the oocytes are fertilized by the man s sperm in a petri dish and then reimplanted in the woman s uterus 7 Describe the basic procedures of intrauterine insemination The woman is given a drug to cause multiple ovulations then sperm is injected into the uterus 8 What problems can arise with in vitro fertilization and intrauterine insemination In vitro fertilization the most common problem is that 2 3 of IVF attempts are unsuccessful In addition multiple fetuses births can occur and unused embryos for IVF are thrown away causing some political and ethical concerns In intrauterine insemination multiple fetuses can be produced causing a greater risk of death or severe malformation unless some fetuses are selectively reduced 9 What are 2 abnormalities that are sometimes found in the female reproductive tract Pelvic inflammatory disease and endometriosis 10 What is an ectopic pregnancy How is it treated A pregnancy that occurs outside of the uterus Developing embryo doesn t implant itself in the uterus but instead in the fallopian tubes ovary cervix or abdominal cavity It is invariably fatal for the fetus The mother can be saved if the pregnancy is terminated 11 What are 2 symptoms of Down syndrome Mild intellectual impairment and characteristic facial appearance 12 What is the genetic cause of and a major risk factor in Down syndrome Down syndrome is caused by trisomy 21 3 copies of chromosome 21 A major risk factor is being a mother over the age of 45 1 in 25 of children born to mothers over 45 have Down syndrome 13 What are several unintentional causes of the death of fetuses Genetic abnormalities due to fertilization by 2 sperm alcohol drugs X ray or anesthesia around the time of ovulation failure to implant Rh incompatalility and ectopic pregnancy 14 What are 4 drugs or procedures that can harm a developing fetus Cocaine heroin excessive alcohol excess vitamins A and C smoking aspirin late in pregnancy marijuana listed in one place in the book not in another estrogens androgens Accutane X rays infections 15 Why is it important for the female to put on extra fat early in pregnancy It is necessary for the fetus during the second half of pregnancy It is harder to gain weight in the second half because so many nutrients and calories are needed for development of the fetus It is important the female gains extra fat early on in pregnancy for the health of herself and the fetus 16 What is the basis for choosing the sex of a child using sperm testing Flow cytometry is used to detect rate of flow of sperm past laser detector X bearing sperm are slightly heavier so based on the flow it can be determined if the sperm carries an X or a Y 17 What is amniocentesis and what is it used for Amniocentesis obtain cells floating in amniotic sac grow in culture check for chromosomal disorders It is used for screening for genetic disorders 18 What is surfactant What stimulates its production Surfactant reduces the surface tension of fluid in the lungs and helps make the small air sacs in the lungs alveoli more stable This keeps them from collapsing when an individual exhales In preparation for breathing air fetuses begin making surfactant while still in the womb The fetus s adrenal steroids stimulate its production 19 What is the main hormone that stimulates uterine contractions Where is it released Oxytocin released from the posterior pituitary 20 Which 2 hormones prepare for lactation Prolactin and Oxytocin 21 What is one health benefit for the baby of breast feeding What is one health benefit for the mother Helps with the babies immune system and causes higher IQ For the mother it helps shrink uterus decreases bleeding helps with weight loss and decreased ovarian breast cancer risks 22 How does breast feeding have contraceptive effects It stimulates prolactin secretion which inhibits GnRH release and therefore FSH LH and ovulation 23 Which two hormones that promote breast feeding also promote maternal behavior Oxytocin and prolactin 24 What are 3 considerations when choosing a method of contraception Reliability reversibility protection against STDs ease of use intrusiveness cost and safety 25 What are 3 advantages and 1 disadvantage of male condoms Advantages cheap and accessible reliable when properly used significant protection against STDs Disadvantages intrusive man must remain erection as long as condom is in use reliability is less than ideal at typical use erotic sensation is reduced 26 What are 1 advantage and 1 disadvantage of female condoms and diaphragms Female Condoms Adv Only contraceptive controlled by the woman that also offers STD protection can be inserted ahead of time Dis Sometimes outer ring can be drawn inside the vagina or man can insert penis outside the condom reduces erotic sensation Diaphragms Can be inserted ahead of time and relatively cheap Disadv very inconvenient and failure rate significantly worse than hormone based contraception 27 How do contraceptive pills work