front 1 All of the following things occur during meiosis I with the exception of one thing. | back 1 A. the homologous chromosome are separated from each toehr B. a single diploid (2n) cell has become two (n) haploid cells C. Sister chromatids are separated from each other D. Portions of maternal chromosomes crossover with equivalent portions of paternal chromosomes. |
front 2 Select the statement which is true regarding independent assortment. | back 2 It is a significant source of genetic variation only during meiosis I |
front 3 Select the statement which is false | back 3 A. Further genetic variation does not occur after meiosis I B. Meiosis II is essential the same process as mitosis except the starting cells C. Crossing over is a source of genetic variability seen in meiosis while independent assortment is a source of genetic variability seen in mitosis. D. Meiosis II is essential the same process as mitosis except the starting cells are haploid (n). E. It is a significant source of genetic variation only during meiosis I. |
front 4 All but one of the following statements are true regarding the differences between early and late spermatids. | back 4 Early spermatids have not undergone meiosis and are still diploid |
front 5 During spermiogenesis ____ | back 5 the acrosome migrates towards the anterior end of the spermatid because its hydrolytic enzymes will be needed for penetration when the sperm contacts the egg during fertilization |
front 6 All but one these events described below occur during spermiogenesis. Select the event that does NOT occur during spermiogenesis. | back 6 Mitochondrial DNA is packaged into the nucleus to be delivered to the egg during fertilization |
front 7 All but one of the following statements is true with regard to the blood testis barrier. Select the one that is false. | back 7 The barrier is made up of astrocytes that surround blood vessels in the testis |
front 8 All but one of the following statements is true of the uterine function. select the statement that is not true of uterine function. | back 8 The narrow portion of the uterus near the cervix is the most typical site of fertilization |
front 9 The oral contraceptive pill, informally called "the pill" contains an estrogen and progesterone or a synthetic mimic of this hormone. The combination of these two hormones taken in the pill and circulating in the blood work because | back 9 the hormones cause the woman's body to mimic the activities of a pregnancy and disrupt the ovarian cycle, preventing ovulation |
front 10 The dartos and cremaster muscles are important to the integrity of the male reproductive system. Which of the following is true about the role they play? | back 10 they regulate the temperature of the testes |
front 11 The ability of sperm cells to move along the ductus deferens is due to | back 11 peristaltic contractions |
front 12 The most important risk for testicular cancer in young males is | back 12 failure of the testis to make their normal descent |
front 13 Which of the following glands is responsible for 70% of the synthesis of semen? | back 13 seminal vesicles |
front 14 Which of the following hormones controls the release of anterior pituitary gonadotropins? | back 14 GnRH |
front 15 The genetic determinate for the male reproductive development is | back 15 the SRY gene |
front 16 The structures that receive the ovulated oocyte, providing a site for fertilization, are called the | back 16 fallopian tubes |
front 17 If gametes were diploid like somatic cells, how many chromosomes would the zygote contain? | back 17 twice the diploid number, and with every succeeding generation, the chromosome number would continue to double and normal development could not occur |
front 18 Human egg and sperm are similar in that ___ | back 18 they have the same number of chromosomes |
front 19 What destroys the zona pellucida sperm-binding receptors? | back 19 zonal inhibiting proteins |
front 20 The result of polyspermy in humans is ___ | back 20 a nonfunctional zygote |
front 21 it is impossible for sperm to be functional (able to fertilize the egg) until after ___ | back 21 they undergo capacitation |
front 22 Milk ejection (the letdown reflex) is stimulated by which of the following hormones associated with pregnancy? | back 22 oxytocin |
front 23 The corpus luteum prevents loss of the implanted embryo through menstruation by secreting ____ | back 23 estrogens and progesterone |
front 24 The placenta, vitally important metabolic organ, is made of a contribution from mother and fetus. Which portion is from the fetus? | back 24 chorion |
front 25 Relaxin is a hormone produced by the placenta and ovaries. The function of this hormone is to ___ | back 25 relax the pubic symphysis |
front 26 Proteases and acrosin are enzymes. How d they function in reproduction? | back 26 they act to break down the protective barriers around the egg, allowing the sperm to penetrate |
front 27 Which of the following is NOT a primary germ layer? | back 27 epiderm |
front 28 The formation of endodermal and ectodermal germ layers occurs at __ | back 28 gastrulation |
front 29 Which hormone maintains the viability of the corpus luteum? | back 29 human chorionic gonadotropin |
front 30 Which of the following events does NOT occur during the first 8 weeks of development? | back 30 myelination of the spinal cord |
front 31 Which of the following is NOT a correct matching of a fetal structure with what it becomes? | back 31 ductus ateriosus--ligamentum teres |
front 32 Which body system of a pregnant woman undergoes the most dramatic physiological changes during pregnancy? | back 32 Cardiovascular system |
front 33 Thalidomide was once used to treat intense nausea and morning sickness in pregnant women. Unfor | back 33 carcinogen teratogen neurotoxin endocrine disruptor |
front 34 Which of the following is not assessed as part of the Apgar score? | back 34 temperature |
front 35 Prior to the let-down reflex, the mammary glands secrete a yellowish fluid | back 35 colostrum |
front 36 How long is the secondary oocyte viable and capable of being fertilized after is it ovulated? | back 36 12-24 hours |
front 37 Select the correct statement about fertilization. | back 37 millions of sperm cells are destroyed by vagina's acidic environment |
front 38 Shortly after implantation ___ | back 38 the trophoblast forms two distinct layers |
front 39 Gastrulation begins when a groove with raised edges called the ___ appears on the dorsal surface of the embryonic disc. | back 39 primitive streak |
front 40 Muscle tissue is formed by ____ | back 40 mesoderm |
front 41 Neural tissue is formed ___ | back 41 ectoderm |
front 42 The trophoblast is mostly responsible for forming the __ | back 42 placental tissue |
front 43 The cardiovascular system of a newborn must be adjusted after the infant takes its first breath. which of the following is also true? | back 43 the ductus arteriosus constricts and is converted to the ligamentum arteriosum |
front 44 Sperm move to the uterine tube through uterine contractions and the energy of their own flagella. What other factor is involved in sperm movement? | back 44 reverse peristalsis of the uterus and the uterine tubes |
front 45 At which stage of labor is the "afterbirth" expelled? | back 45 placental |
front 46 Fertilization generally occurs in the ___ | back 46 fallopian tubes |
front 47 which of the following female structures is homologous to the male scrotum? | back 47 labia majora |
front 48 In humans, separation of the cells at the two-cell state following fertilization may lead to he production of twins, which in this case would be ____ | back 48 genetically identical |
front 49 how many alleles exist for a given gene? | back 49 each gene can have different number of alleles |
front 50 Select the statement that best describes the difference between a gene and an allele | back 50 Genes express a specific trait while alleles are variations of a particular gene that in variation we see in a genetic individual trait |
front 51 if a person is homozygous for a particular trait this means | back 51 the person has two identical alleles for the gene responsible for the trait |
front 52 is it possible for a baby to have type O blood if neither parent is type O | back 52 true |
front 53 Recessive allele is best defined | back 53 only expressed if present in a double dose |
front 54 Of the different sources of genetic variability which one cause the variation in the combinations of homologs from paternal and maternal linage found within a haploid cell. | back 54 crossing over |
front 55 of the different sources of genetic variability which one produces the variation in the combinations of alleles on a single chromosome | back 55 independent assortment |
front 56 of the different sources of genetic variability which one produces the variation seen by the combination of any particular male gamete to any particular female gamete | back 56 random fertilization |
front 57 of the different sources of genetic variability which one could be define as permanent, transmissible changes to the DNA coding sequence that are often caused by outside environmental factors? | back 57 mutation |
front 58 in meiosis the spermatozoa that are produced are genetically unlike each other and unlike the cel that produces them. this is one reason for great variation. What causes this effect? | back 58 crossing over and independent assortment only |