Fetal Development - Ch 3

A woman asks the nurse, "What protects my baby's umbilical cord from being squashed while the baby's inside of me?" The nurse's best response is: a. "Your baby's umbilical cord is surrounded by connective tissue called Wharton jelly, which prevents compression of the blood vessels and ensures continued nourishment of your baby." b. "Your baby's umbilical floats around in blood anyway." c. "You don't need to worry about things like that." d. "The umbilical cord is a group of blood vessels that are very well protected by the placenta."

ANS: A "Your baby's umbilical cord is surrounded by connective tissue called Wharton jelly, which prevents compression of the blood vessels and ensures continued nourishment of your baby" is the most appropriate response. "Your baby's umbilical floats around in blood anyway" is inaccurate. "You don't need to worry about things like that" is an inappropriate response.It negates the client's need for teaching and discounts her feelings. The placenta does not protect the umbilical cord. The cord is protected by the surrounding Wharton jelly.

A maternity nurse should be aware of which fact about the amniotic fluid? a. It serves as a source of oral fluid and a repository for waste from the fetus. b. The volume remains about the same throughout the term of a healthy pregnancy. c. A volume of less than 300 mL is associated with gastrointestinal malformations. d. A volume of more than 2 L is associated with fetal renal abnormalities.

ANS: A Amniotic fluid serves as a source of oral fluid, serves as a repository for waste from the fetus, cushions the fetus, and helps maintain a constant body temperature. The volume of amniotic fluid changes constantly. Too little amniotic fluid (oligohydramnios) is associated with renal abnormalities. Too much amniotic fluid (hydramnios) is associated with gastrointestinal and other abnormalities.

A key finding from the Human Genome Project is: a. Approximately 20,000 genes make up the genome. b. All human beings are 80.99% identical at the DNA level. c. Human genes produce only one protein per gene; other mammals produce three proteins per gene. d. Single gene testing will become a standardized test for all pregnant clients in the future.

ANS: A Approximately 20,500 genes make up the human genome; this is only twice as many as make up the genomes of roundworms and flies. Human beings are 99.9% identical at theDNA level. Most human genes produce at least three proteins. Single gene testing (e.g., alpha-fetoprotein) is already standardized for prenatal care.

The nurse caring for the laboring woman should know that meconium is produced by: a. Fetal intestines. c. Amniotic fluid. b. Fetal kidneys. d. The placenta.

ANS: A As the fetus nears term, fetal waste products accumulate in the intestines as dark green- to-black, tarry meconium.

A nurse is teaching a prenatal class. The nurse teaches that during weeks 25 to 28, which fetal development occurs? a. Eyes reopen. b. Vernix caseosa covers the skin. c. Lanugo may develop. d. Brown fat is deposited.

ANS: A During this time frame the eyes reopen, and the fetus becomes plumper with smoother skin. The other changes occur during weeks 17 to 20.

The placenta allows exchange of oxygen, nutrients, and waste products between the mother and fetus by a. contact between maternal blood and fetal capillaries within the chorionic villi. b. interaction of maternal and fetal pH levels within the endometrial vessels. c. a mixture of maternal and fetal blood within the intervillous spaces. d. passive diffusion of maternal carbon dioxide and oxygen into the fetal capillaries.

ANS: A Fetal capillaries within the chorionic villi are bathed with oxygen- and nutrient-rich maternal blood within the intervillous spaces. The endometrial vessels are part of the uterus. There is no interaction with the fetal blood at this point. Maternal and fetal blood do not normally mix. Maternal carbon dioxide does not enter into the fetal circulation.

The placenta allows exchange of oxygen, nutrients, and waste products between the mother and fetus by: a. Contact between maternal blood and fetal capillaries within the chorionic villi. b. Interaction of maternal and fetal pH levels within the endometrial vessels.c. A mixture of maternal and fetal blood within the intervillous spaces. d. Passive diffusion of maternal carbon dioxide and oxygen into the fetal capillaries.

ANS: A Fetal capillaries within the chorionic villi are bathed with oxygen-rich and nutrient-rich maternal blood within the intervillous spaces. The endometrial vessels are part of the uterus. There is no interaction with the fetal blood at this point. Maternal and fetal blood do not normally mix.Maternal carbon dioxide does not enter into the fetal circulation.

Many parents-to-be have questions about multiple births. Maternity nurses should be able to tell them that: a. Twinning and other multiple births are increasing because of the use of fertility drugs and delayed childbearing. b. Dizygotic twins (two fertilized ova) have the potential to be conjoined twins. c. Identical twins are more common in white families. d. Fraternal twins are same gender, usually male.

ANS: A If the parents-to-be are older and have taken fertility drugs, they would be very interested to know about twinning and other multiple births. Conjoined twins aremonozygotic; they are from a single fertilized ovum in which division occurred very late. Identical twins show no racial or ethnic preference; fraternal twins are more common among African-American women. Fraternal twins can be different genders or the same gender. Identical twins are the same gender.

The nurse is assessing the knowledge of new parents with a child born with maple syrup urine disease (MSUD). This is an autosomal recessive inherited disorder, which means that: a. Both genes of a pair must be abnormal for the disorder to be expressed. b. Only one copy of the abnormal gene is required for the disorder to be expressed. c. The disorder occurs in males and heterozygous females. d. The disorder is carried on the X chromosome.

ANS: A MSUD is a type of autosomal recessive inheritance disorder in which both genes of a pair must be abnormal for the disorder to be expressed. MSUD is not an X-linked dominant or recessive disorder or an autosomal dominant inheritance disorder.

With regard to prenatal genetic testing, nurses should be aware that: a. Maternal serum screening can determine whether a pregnant woman is at risk of carrying a fetus with Down syndrome. b. Carrier screening tests look for gene mutations of people already showing symptoms of a disease. c. Predisposition testing predicts with near certainty that symptoms will appear. d. Presymptomatic testing is used to predict the likelihood of breast cancer.

ANS: A Maternal serum screening identifies the risk for the neural tube defect and the specific chromosome abnormality involved in Down syndrome. Carriers of some diseases, such as sickle cell disease, do not display symptoms. Predisposition testing determines susceptibility, such as for breast cancer. presymptomatic testing indicates that symptoms are certain to appear if the gene is present.

The nurse caring for a pregnant client knows that her health teaching regarding fetal circulation has been effective when the client reports that she has been sleeping: a. In a side-lying position. b. On her back with a pillow under her knees. c. With the head of the bed elevated. d. On her abdomen.

ANS: A Optimal circulation is achieved when the woman is lying at rest on her side. Decreased uterine circulation may lead to intrauterine growth restriction. Previously it was believed that the left lateral position promoted maternal cardiac output, enhancing blood flow to the fetus. However, it is now known that the side-lying position enhances uteroplacental blood flow. If a woman lies on her back with the pressure of the uterus compressing the vena cava, blood return to the right atrium is diminished. Although having the head of the bed elevated is recommended and ideal for later in pregnancy, the woman still must maintain a lateral tilt to the pelvis to avoid compression of the vena cava. Many women find lying on her abdomen uncomfortable as pregnancy advances. Side-lying is the ideal position to promote blood flow to the fetus.

A new mother asks the nurse about the "white substance" covering her infant. The nurse explains that the purpose of vernix caseosa is to: a. Protect the fetal skin from amniotic fluid. b. Promote normal peripheral nervous system development. c. Allow transport of oxygen and nutrients across the amnion. d. Regulate fetal temperature.

ANS: A Prolonged exposure to amniotic fluid during the fetal period could result in breakdown of the skin without the protection of the vernix caseosa. Normal development of the peripheral nervous system is dependent on nutritional intake of the mother. The amnion is the inner membrane that surrounds the fetus. It is not involved in the oxygen and nutrient exchange. The amniotic fluid aids in maintaining fetal temperature.

The nurse must be cognizant that an individual's genetic makeup is known as his or her: a. Genotype. c. Karyotype. b. Phenotype. d. Chromotype

ANS: A The genotype comprises all the genes the individual can pass on to a future generation. The phenotype is the observable expression of an individual's genotype. The karyotype is a pictorial analysis of the number, form, and size of an individual's chromosomes. Genotype refers to an individual's genetic makeup.

Which statement is accurate about the development of fetal organs and systems? a. The cardiovascular system is the first organ system to function in the developing human. b. Hematopoiesis originating in the yolk sac begins in the liver at 10 weeks. c. The body changes from straight to C-shaped at 8 weeks. d. The gastrointestinal system is mature at 32 weeks.

ANS: A The heart is developmentally complete by the end of the embryonic stage. Hematopoiesis begins in the liver during the 6th week. The body becomes C-shaped at 21 weeks. The gastrointestinal system is complete at 36 weeks.

The student learns about shunts that support fetal circulation. Which of the following are included in this support system? (Select all that apply.) a. Ductus venosus b. Foramen ovale c. Ductus arteriosus d. Foramen magnum e. Ductus deferens

ANS: A, B, C The ductus venosus, foramen ovale, and ductus arteriosus are part of fetal circulation. The foramen magnum is located at the base of the skull. The ductus (or vas) deferens is part of the male reproductive system.

The nursing faculty explains that the fetus can survive in a low-oxygen environment due to which of the following? (Select all that apply.) a. Fetal hemoglobin carries more oxygen than an adult's. b. The fetus has higher average hemoglobin and hematocrit. c. Hemoglobin carries more oxygen at low partial pressures of carbon dioxide. d. Fetal blood is more acidic than the maternal blood. e. The fetus does not need gas exchange while in utero.

ANS: A, B, C The fetus can survive in low oxygen environments due to its hemoglobin being able to carry more oxygen that the mom, having a higher level of hemoglobin and hematocrit, and the fact that hemoglobin can carry more oxygen at low partial pressures of carbon dioxide. Fetal blood is alkaline. The fetus does need gas exchange in utero.

The nurse assesses pregnant women for exposure to human teratogens, including which of the following? (Select all that apply.) a. Infections b. Radiation c. Maternal conditions d. Drugs e. Chemicals

ANS: A, B, C, D Exposure to radiation and a number of infections may result in profound congenital deformities. These include varicella, rubella, syphilis, parvovirus, CMV, and toxoplasmosis. Certain maternal conditions such as diabetes and PKU may also affect organs and other parts of the embryo during this developmental period. Drugs such as antiseizure medication and some antibiotics, as well as chemicals including lead, mercury, tobacco, and alcohol, also may result in structural and functional abnormalities. Coffee is not considered a teratogen

Congenital disorders refer to conditions that are present at birth. These disorders may be inherited and caused by environmental factors or maternal malnutrition. Toxic exposures have the greatest effect on development between 15 and 60 days of gestation. For the nurse to be able to conduct a complete assessment of the newly pregnant client, she should understand the significance of exposure to known human teratogens. These include(Select all that apply): a. Infections. b. Radiation. c. Maternal conditions. d. Drugs. e. Chemicals.

ANS: A, B, C, D, E Exposure to radiation and numerous infections may result in profound congenital deformities. These include but are not limited to varicella, rubella, syphilis, parvovirus, cytomegalovirus, and toxoplasmosis. Certain maternal conditions such as diabetes and phenylketonuria may also affect organs and other parts of the embryo during this developmental period. Drugs such as antiseizure medication and some antibiotics as well as chemicals, including lead, mercury, tobacco, and alcohol, also may result in structural and functional abnormalities

Which congenital malformations result from multifactorial inheritance (Select all that apply)? a. Cleft lip b. Congenital heart disease c. Cri du chat syndrome d. Anencephaly e. Pyloric stenosis

ANS: A, B, D, E All these congenital malformations are associated with multifactorial inheritance. Cri du chat syndrome is related to a chromosome deletion.

The nursing faculty teaches that the placenta produces many hormones necessary for normal pregnancy. These include (Select all that apply.) a. human chorionic gonadotropin (hCG). b. insulin. c. estrogen. d. progesterone. e. testosterone.

ANS: A, C, D The placenta produces hCG, estrogen, and progesterone. It does not produce insulin or testosterone.

Along with gas exchange and nutrient transfer, the placenta produces many hormones necessary for normal pregnancy. These include (select all that apply) a. Human chorionic gonadotropin (hCG) b. Insulin c. Estrogen d. Progesterone e. Testosterone

ANS: A, C, D hCG causes the corpus luteum to persist and produce the necessary estrogens and progesterone for the first 6 to 8 weeks. Estrogens cause enlargement of the woman's uterus and breasts; cause growth of the ductal system in the breasts; and, as term approaches, play a role in the initiation of labor. Progesterone causes the endometrium to change, providing early nourishment. Progesterone also protects against spontaneous abortion by suppressing maternal reactions to fetal antigens and reduces unnecessary uterine contractions. Other hormones produced by the placenta include hCT, hCA, and numerous growth factors. Human placental lactogen promotes normal nutrition and growth of the fetus and maternal breast development for lactation. This hormone decreases maternal insulin sensitivity and utilization of glucose, making more glucose available for fetal growth. If a Y chromosome is present in the male fetus, hCG causes the fetal testes to secrete testosterone necessary for the normal development of male reproductive structures.

Which statement related to oogenesis is correct? a. Two million primary oocytes will mature. b. At birth, all ova are contained in the female's ovaries. c. The oocytes complete their division during fetal life. d. Monthly, at least two oocytes mature.

ANS: B All of the cells that may undergo meiosis in a woman's lifetime are contained in the ovaries at birth. Only 400 to 500 ova will mature during the approximately 35 years of a woman's reproductive life. The primary oocytes begin their first meiotic division during fetal life but remain suspended until puberty. Every month, one primary oocyte matures and completes meiotic division yielding two unequal cells.

A woman who is 16 weeks pregnant asks the nurse, "Is it possible to tell by ultrasound if the baby is a boy or girl yet?" The best answer is a. "A baby's sex is determined as soon as conception occurs, and the differences are apparent." b. "The baby has developed enough that we can determine the sex by examining the genitals through ultrasound." c. "Boys and girls look alike until approximately 20 weeks after conception, and then they begin to look different." d. "It might be possible to determine your baby's sex, but the external organs look very similar right now."

ANS: B Although gender is determined at conception, the external genitalia of males and females look similar through the 9th week. By the 12th week, the external genitalia are distinguishable as male or female.

A woman who is 16 weeks pregnant asks the nurse, "Is it possible to tell by ultrasound if the baby is a boy or girl yet?" The best answer is: a. "A baby's sex is determined as soon as conception occurs." b. "The baby has developed enough that we can determine the sex by examining the genitals through ultrasound." c. "Boys and girls look alike until about 20 weeks after conception, and then they begin to look different." d. "It might be possible to determine your baby's sex, but the external organs look very similar right now."

ANS: B Although gender is determined at conception, the external genitalia of males and females look similar through the ninth week. By the twelfth week, the external genitalia are distinguishable as male or female.

With regard to chromosome abnormalities, nurses should be aware that: a. They occur in approximately 10% of newborns. b. Abnormalities of number are the leading cause of pregnancy loss. c. Down syndrome is a result of an abnormal chromosome structure. d. Unbalanced translocation results in a mild abnormality that the child will outgrow

ANS: B Aneuploidy is an abnormality of number that also is the leading genetic cause of mental retardation. Chromosome abnormalities occur in less than 1% of newborns. Down syndrome is the most common form of trisomal abnormality, an abnormality of chromosome number (47 chromosomes). Unbalanced translocation is an abnormality of chromosome structure that often has serious clinical effects.

A patient is sent from the physician's office for assessment of oligohydramnios. The nurse is aware that this condition can result in a. excessive fetal urine secretion. b. newborn respiratory distress. c. central nervous system abnormality. d. gastrointestinal blockage.

ANS: B Because an abnormally small amount of amniotic fluid restricts normal lung development, the infant may have inadequate respiratory function after birth, when the placenta no longer performs respiratory function. Oligohydramnios may be caused by a decrease in urine secretion. Excessive amniotic fluid production may occur when the fetus has a central nervous system abnormality. Excessive amniotic fluid production may occur when the gastrointestinal tract prevents normal ingestion of amniotic fluid.

In presenting to obstetric nurses interested in genetics, the genetic nurse identifies the primary risk(s) associated with genetic testing as: a. Anxiety and altered family relationships. b. Denial of insurance benefits. c. High false-positive results associated with genetic testing. d. Ethnic and socioeconomic disparity associated with genetic testing.

ANS: B Decisions about genetic testing are shaped by socioeconomic status and the ability to pay for the testing. Some types of genetic testing are expensive and are not covered by insurance benefits. Anxiety and altered family relationships, high false-positive results, and ethnic and socioeconomic disparity are factors that may be difficulties associated with genetic testing, but they are not risks associated with testing

A woman is 15 weeks pregnant with her first baby. She asks how long it will be before she feels the baby move. The best answer is: a. "You should have felt the baby move by now." b. "Within the next month, you should start to feel fluttering sensations."c. "The baby is moving; however, you can't feel it yet." d. "Some babies are quiet, and you don't feel them move."

ANS: B Maternal perception of fetal movement usually begins 16 to 20 weeks after conception. Because this is her first pregnancy, movement is felt toward the later part of the 16- to 20-week time period. Stating that "you should have felt the baby move by now" is incorrect and may be alarming to the patient. Fetal movement should be felt by 16 to 20 weeks. If movement is not felt by the end of that time, further assessment will be necessary.

A woman is 16 weeks pregnant with her first baby. She asks how long it will be before she feels the baby move. The best answer is a. "You should have felt the baby move by now." b. "Within the next month, you should start to feel fluttering sensations." c. "The baby is moving, but you can't feel it yet." d. "Some babies are quiet, and you don't feel them move."

ANS: B Maternal perception of fetal movement usually begins 17 to 20 weeks after conception, particularly if this is the first pregnancy. "The baby is moving, but you can't feel it yet" is a true statement. The fetus's movements are not strong enough to be felt until 17 to 20 weeks; however, this statement does not answer the concern of the woman. If no movement is felt at the end of 20 weeks, further assessment is needed.

A man's wife is pregnant for the third time. One child was born with cystic fibrosis, and the other child is healthy. The man wonders what the chance is that this child will have cystic fibrosis. This type of testing is known as: a. Occurrence risk. c. Predictive testing. b. Recurrence risk. d. Predisposition testing.

ANS: B The couple already has a child with a genetic disease so they will be given a recurrence risk test. If a couple has not yet had children but are known to be at risk for having children with a genetic disease, they are given an occurrence risk test. Predictive testing is used to clarify the genetic status of an asymptomatic family member. Predisposition testing differs from presymptomatic testing in that a positive result does not indicate 100% risk of a condition developing.

As relates to the structure and function of the placenta, the maternity nurse should be aware that: a. As the placenta widens, it gradually thins to allow easier passage of air and nutrients. b. As one of its early functions, the placenta acts as an endocrine gland. c. The placenta is able to keep out most potentially toxic substances such as cigarette smoke to which the mother is exposed. d. Optimal blood circulation is achieved through the placenta when the woman is lying on her back or standing.

ANS: B The placenta produces four hormones necessary to maintain the pregnancy. The placenta widens until week 20 and continues to grow thicker. Toxic substances such as nicotine and carbon monoxide readily cross the placenta into the fetus. Optimal circulation occurs when the woman is lying on her side.

With regard to the structure and function of the placenta, the maternity nurse should be aware that a. as the placenta widens, it gradually thins to allow easier passage of air and nutrients. b. as one of its early functions, the placenta acts as an endocrine gland. c. the placenta is able to keep out most potentially toxic substances, such as cigarette smoke, to which the mother is exposed. d. optimal blood circulation is achieved through the placenta when the woman is lying on her back or standing.

ANS: B The placenta produces four hormones necessary to maintain the pregnancy. The placenta widens until week 20 and continues to grow thicker. Toxic substances such as nicotine and carbon monoxide readily cross the placenta into the fetus. Optimal circulation occurs when the woman is lying on her side.

The nursing faculty explains to students that the upper uterus is the best place for the fertilized ovum to implant because it is here that the a. placenta attaches most firmly. b. developing baby is best nourished. c. uterine endometrium is softer. d. maternal blood flow is lower.

ANS: B The uterine fundus is richly supplied with blood and has the thickest endometrium, both of which promote optimal nourishment of the fetus. If the placenta attaches too deeply, it does not easily detach after birth. Softness is not a concern with implantation; attachment and nourishment are the major concerns. The blood supply is rich in the fundus, which allows for optimal nourishment of the fetus.

You are a maternal-newborn nurse caring for a mother who just delivered a baby born with Down syndrome. What nursing diagnosis would be the most essential in caring for the mother of this infant? a. Disturbed body image c. Anxiety b. Interrupted family processes d. Risk for injury

ANS: B This mother likely will experience a disruption in the family process related to the birth of a baby with an inherited disorder. Women commonly experience "body image disturbances in the postpartum period"; however, this is unrelated to giving birth to a child with Down syndrome. The mother likely will have a mix of emotions that may include anxiety, guilt, and denial, but this is not the most essential nursing diagnosis for this family. "Risk for injury" is not an applicable nursing diagnosis.

A pregnant woman at 25 weeks' gestation tells the nurse that she dropped a pan last week and her baby jumped at the noise. Which response by the nurse is most accurate? a. "That must have been a coincidence; babies can't respond like that." b. "The fetus is demonstrating the aural reflex."c. "Babies respond to sound starting at about 24 weeks of gestation." d. "Let me know if it happens again; we need to report that to your midwife."

ANS: C "Babies respond to sound starting at about 24 weeks of gestation" is an accurate statement. "That must have been a coincidence; babies can't respond like that" is inaccurate. Acoustic stimulations can evoke a fetal heart rate response. There is no such thing as an aural reflex. The statement, "Let me know if it happens again; we need to report that to your midwife" is not appropriate; it gives the impression that something is wrong.

The measurement of lecithin in relation to sphingomyelin (L/S ratio) is used to determine fetal lung maturity. Which ratio reflects maturity of the lungs? a. 1.4:1 c. 2:1 b. 1.8:1 d. 1:1

ANS: C A ratio of 2:1 indicates a two-to-one ratio of L/S, an indicator of lung maturity. Ratios of 1.4:1, 1.8:1, and 1:1 indicate immaturity of the fetal lungs.

With regard to the development of the respiratory system, maternity nurses should be understand that: a. The respiratory system does not begin developing until after the embryonic stage. b. The infant's lungs are considered mature when the lecithin/sphingomyelin (L/S) ratio is 1:1, at about 32 weeks. c. Maternal hypertension can reduce maternal-placental blood flow, accelerating lung maturity. d. Fetal respiratory movements are not visible on ultrasound scans until at least 16 weeks.

ANS: C A reduction in placental blood flow stresses the fetus, increases blood levels of corticosteroids, and accelerates lung maturity. Development of the respiratory system begins during the embryonic phase and continues into childhood. The infant's lungs are mature when the L/S ratio is 2:1, at about 35 weeks. Lung movements have been seen on ultrasound scans at 11 weeks.

During a pregnancy group meeting, the nurse teaches patients that the fetal period is best described as one of a. development of basic organ systems. b. resistance of organs to damage from external agents. c. maturation of organ systems. d. development of placental oxygen-carbon dioxide exchange

ANS: C During the fetal period, the body systems grow in size and mature in function to allow independent existence after birth. Basic organ systems are developed during the embryonic period. The organs are always at risk for damage from external sources; however, the older the fetus, the more resistant the organs will be. The greatest risk is when the organs are developing. The placental system is complete by week 12, but that is not the best description of the fetal period.

The nurse is providing genetic counseling for an expectant couple who already have a child with trisomy 18. The nurse should: a. Tell the couple they need to have an abortion within 2 to 3 weeks. b. Explain that the fetus has a 50% chance of having the disorder. c. Discuss options with the couple, including amniocentesis to determine whether the fetus is affected. d. Refer the couple to a psychologist for emotional support

ANS: C Genetic testing, including amniocentesis, would need to be performed to determine whether the fetus is affected. The couple should be given information about the likelihood of having another baby with this disorder so that they can make an informed decision. A genetic counselor is the best source for determining genetic probability ratios. The couple eventually may need emotional support, but the status of the pregnancy must be determined first.

A couple has been counseled for genetic anomalies. They ask you, "What is karyotyping?" Your best response is: a. "Karyotyping will reveal if the baby's lungs are mature." b. "Karyotyping will reveal if your baby will develop normally." c. "Karyotyping will provide information about the gender of the baby and the number and structure of the chromosomes." d. "Karyotyping will detect any physical deformities the baby has."

ANS: C Karyotyping provides genetic information such as gender and chromosome structure. The L/S, not karyotyping, reveals lung maturity. Although karyotyping can detect genetic anomalies, the range of normal is nondescriptive. Although karyotyping can detect genetic anomalies, not all such anomalies display obvious physical deformities. The term deformities is a nondescriptive word. Physical anomalies may be present that are not detected by genetic studies (e.g., cardiac malformations).

In practical terms regarding genetic health care, nurses should be aware that: a. Genetic disorders affect people of all socioeconomic backgrounds, races, and ethnic groups equally. b. Genetic health care is more concerned with populations than individuals. c. The most important of all nursing functions is providing emotional support to the family during counseling. d. Taking genetic histories is the province of large universities and medical centers.

ANS: C Nurses should be prepared to help with various stress reactions from a couple facing the possibility of a genetic disorder. Although anyone may have a genetic disorder, certain disorders appear more often in certain ethnic and racial groups. Genetic health care is highly individualized because treatments are based on the phenotypic responses of the individual. Individual nurses at any facility can take a genetic history, although larger facilities may have better support services.

A woman's cousin gave birth to an infant with a congenital heart anomaly. The woman asks the nurse when such anomalies occur during development. Which response by the nurse is most accurate? a. "We don't really know when such defects occur." b. "It depends on what caused the defect." c. "They occur between the third and fifth weeks of development." d. "They usually occur in the first 2 weeks of development."

ANS: C The cardiovascular system is the first organ system to function in the developing human. Blood vessel and blood formation begins in the third week, and the heart is developmentally complete in the fifth week. "We don't really know when such defects occur" is an inaccurate statement. Regardless of the cause, the heart is vulnerable during its period of development, the third to fifth weeks. "They usually occur in the first 2 weeks of development" is an inaccurate statement.

1. A father and mother are carriers of phenylketonuria (PKU). Their 2-year-old daughter has PKU. The couple tells the nurse that they are planning to have a second baby. Because their daughter has PKU, they are sure that their next baby won't be affected. What response by the nurse is most accurate? a. "Good planning; you need to take advantage of the odds in your favor." b. "I think you'd better check with your doctor first." c. "You are both carriers, so each baby has a 25% chance of being affected." d. "The ultrasound indicates a boy, and boys are not affected by PKU."

ANS: C The chance is one in four that each child produced by this couple will be affected by PKU disorder. This couple still has an increased likelihood of having a child with PKU. Having one child already with PKU does not guarantee that they will not have another. These parents need to discuss their options with their physician. However, an opportune time has presented itself for the couple to receive correct teaching about inherited genetic risks. No correlation exists between gender and inheritance of the disorder because PKU is an autosomal recessive disorder.

Sally comes in for her first prenatal examination. This is her first child. She asks you (the nurse), "How does my baby get air inside my uterus?" The correct response is: a. "The baby's lungs work in utero to exchange oxygen and carbon dioxide."b. "The baby absorbs oxygen from your blood system." c. "The placenta provides oxygen to the baby and excretes carbon dioxide into your bloodstream." d. "The placenta delivers oxygen-rich blood through the umbilical artery to the baby's abdomen."

ANS: C The placenta functions by supplying oxygen and excreting carbon dioxide to the maternal bloodstream. The fetal lungs do not function for respiratory gas exchange in utero. The baby does not simply absorb oxygen from a woman's blood system. Blood and gas transport occur through the placenta. The placenta delivers oxygen-rich blood through the umbilical vein and not the artery.

A young patient comes in for her first prenatal examination. This is her first child. She asks "How does my baby get air inside my uterus?" The correct response is a. "The baby's lungs work in the uterus to exchange oxygen and carbon dioxide." b. "The baby absorbs oxygen from your blood system." c. "The placenta provides oxygen to the baby and excretes carbon dioxide into your bloodstream." d. "The placenta delivers oxygen-rich blood through the umbilical artery to the baby's abdomen."

ANS: C The placenta functions by supplying oxygen and excreting carbon dioxide to the maternal bloodstream. The fetal lungs do not function for respiratory gas exchange in utero. The baby does not simply absorb oxygen from a woman's blood system. Blood and gas transport occurs through the placenta. The placenta delivers oxygen-rich blood through the umbilical vein, not artery.

At approximately _____ weeks of gestation, lecithin is forming on the alveolar surfaces, the eyelids open, and the fetus measures approximately 27 cm crown to rump and weighs approximately 1110 g. a. 20 c. 28 b. 24 d. 30

ANS: C These milestones human development occur at approximately 28 weeks.

The most basic information a maternity nurse should have concerning conception is that: a. Ova are considered fertile 48 to 72 hours after ovulation. b. Sperm remain viable in the woman's reproductive system for an average of 12 to 24 hours. c. Conception is achieved when a sperm successfully penetrates the membrane surrounding the ovum. d. Implantation in the endometrium occurs 6 to 10 days after conception.

ANS: D After implantation, the endometrium is called the decidua. Ova are considered fertile for about 24 hours after ovulation. Sperm remain viable in the woman's reproductive system for an average of 2 to 3 days. Penetration of the ovum by the sperm is called fertilization. Conception occurs when the zygote, the first cell of the new individual, is formed.

The _____ is/are responsible for oxygen and carbon dioxide transport to and from the maternal bloodstream. a. Decidua basalis c. Germ layer b. Blastocyst d. Chorionic villi

ANS: D Chorionic villi are fingerlike projections that develop out of the trophoblast and extend into the blood-filled spaces of the endometrium. The villi obtain oxygen and nutrients from the maternal bloodstream and dispose of carbon dioxide and waste products into the maternal blood. The decidua basalis is the portion of the decidua (endometrium) under the blastocyst where the villi attach. The blastocyst is the embryonic development stage after the morula. Implantation occurs at this stage. The germ layer is a layer of the blastocyst.

When explaining twin conception, the nurse points out that dizygotic twins develop from a. a single fertilized ovum and are always of the same sex. b. a single fertilized ovum and may be the same sex or different sexes. c. two fertilized ova and are the same sex. d. two fertilized ova and may be the same sex or different sexes.

ANS: D Dizygotic twins are two different zygotes, each conceived from a single ovum and a single sperm. They may be both male, both female, or one male and one female. A single fertilized ovum that produces twins is called monozygotic. Monozygotic twins are always the same sex. Dizygotic twins are from two fertilized ova and may or may not be the same sex.

A woman who is 8 months pregnant asks the nurse, "Does my baby have any antibodies to fight infection?" The most appropriate response by the nurse is: a. "Your baby has all the immune globulins necessary: IgG, IgM, and IgA." b. "Your baby won't receive any antibodies until he is born and you breastfeed him." c. "Your baby does not have any antibodies to fight infection." d. "Your baby has IgG and IgM."

ANS: D During the third trimester, the only immune globulins that crosses the placenta, IgG, provides passive acquired immunity to specific bacterial toxins. The fetus produces IgM by the end of the first trimester. IgA is not produced by the baby. By the third trimester, the fetus has IgG and IgM. Breastfeeding supplies the baby with IgA. "Your baby does not have any antibodies to fight infection" is an inaccurate statement.

With regard to the estimation and interpretation of the recurrence of risks for genetic disorders, nurses should be aware that: a. With a dominant disorder, the likelihood of the second child also having the condition is 100%. b. An autosomal recessive disease carries a one in eight risk of the second child also having the disorder. c. Disorders involving maternal ingestion of drugs carry a one in four chance of being repeated in the second child. d. The risk factor remains the same no matter how many affected children are already in the family.

ANS: D Each pregnancy is an independent event. The risk factor (e.g., one in two, one in four) remains the same for each child, no matter how many children are born to the family. In a dominant disorder, the likelihood of recurrence in subsequent children is 50% (one in two). An autosomal recessive disease carries a one in four chance of recurrence. In disorders involving maternal ingestion of drugs, subsequent children would be at risk only if the mother continued to take drugs; the rate of risk would be difficult to calculate.

The most basic information a maternity nurse should have concerning conception is a. ova are considered fertile 48 to 72 hours after ovulation. b. sperm remain viable in the woman's reproductive system for an average of 12 to 24 hours. c. conception is achieved when a sperm successfully penetrates the membrane surrounding the ovum. d. implantation in the endometrium occurs 6 to 10 days after conception.

ANS: D Implantation occurs 6 to 10 days after conception and is complete after 10 days. Ova are considered fertile for approximately 24 hours after ovulation. Sperm remain viable in the woman's reproductive system for an average of 2 to 3 days. Penetration of the ovum by the sperm is called fertilization. Conception occurs when the zygote, the first cell of the new individual, is formed.

A new mother is distresses over the "white substance" covering her infant because it "looks ugly." What action by the nurse is most appropriate? a. Scrub the substance off of the baby. b. Reassure the mom that it will go away. c. Report the findings to the provider. d. Explain that the vernix caseosa protects fetal skin from amniotic fluid.

ANS: D Prolonged exposure to amniotic fluid during the fetal period could result in breakdown of the skin without the protection of the vernix caseosa. This can be washed off gently, when the baby gets the first bath. Although it will not remain, this statement does not explain the purpose of the substance. This does not need to be reported.

Some of the embryo's intestines remain within the umbilical cord during the embryonic period because the: a. Umbilical cord is much larger at this time than it will be at the end of pregnancy. b. Intestines begin their development within the umbilical cord. c. Nutrient content of the blood is higher in this location. d. Abdomen is too small to contain all the organs while they are developing.

ANS: D The abdominal contents grow more rapidly than the abdominal cavity, so part of their development takes place in the umbilical cord. By 10 weeks of gestation, the abdomen is large enough to contain them. Intestines begin their development within the umbilical cord, but only because the liver and kidneys occupy most of the abdominal cavity. Blood supply is adequate in all areas.

The student nurse learns that some of the embryo's intestines remain within the umbilical cord during the embryonic period because the a. umbilical cord is much larger at this time than it will be at the end of pregnancy. b. intestines begin their development within the umbilical cord. c. nutrient content of the blood is higher in this location. d. abdomen is too small to contain all the organs while they are developing.

ANS: D The abdominal contents grow more rapidly than the abdominal cavity, so part of their development takes place in the umbilical cord. By 10 weeks, the abdomen is large enough to contain them. The intestines remain within the umbilical cord only until approximately week 10. Intestines begin their development within the umbilical cord but only because the liverand kidneys occupy most of the abdominal cavity. All the intestines are within the abdominal cavity around week 10.

While teaching an early pregnancy class, the nurse explains that the morula is a a. fertilized ovum before mitosis begins. b. flattened disk-shaped layer of cells within a fluid-filled sphere. c. double layer of cells that becomes the placenta. d. solid ball composed of the first cells formed after fertilization.

ANS: D The morula is so named because it resembles a mulberry. It is a solid ball of 12 to 16 cells that develops after fertilization. The fertilized ovum is called the zygote. This is the embryonic disk. It will develop into the baby. The placenta is formed from two layers of cells: the trophoblast, which is the other portion of the fertilized ovum, and the decidua, which is the portion of the uterus where implantation occurs.

After implantation, tiny projections develop out of the trophoblast and extend into the endometrium. These projections are referred to as a. decidua basalis. b. decidua capsularis. c. decidua vera. d. chorionic villi.

ANS: D These villi are vascular processes that obtain oxygen and nutrients from the maternal bloodstream and dispose of carbon dioxide and waste products into the maternal blood. The deciduas basalis is the portion of the endometrium where the chorionic villi tap into the maternal blood vessels. The deciduas capsularis is the portion of the endometrium that covers the blastocyst. The portion of the endometrium that lines the rest of the uterus is called decidua vera.

What does the student learn about recent trends in multiple births? a. The rate of twin births has declined. b. The rate of higher order pregnancies has increased. c. Higher order pregnancies are now very rare. d. Twinning is the most common form of multiple pregnancy.

ANS: D Twinning is the most common form of multiple pregnancy, and the rate has been increasing, not declining. Higher order births increased for a time but have now decreased, although they are not rare.

The nurse has completed a presentation on reproduction. Which participant's statement indicates that teaching has been successful? 1. "Ova separate into two unequally sized cells." 2. "A male is born with all the sperm he will ever produce." 3. "Females create new ova throughout their reproductive life." 4. "Each primary spermatocyte divides into four haploid cells."

Answer: 1 Explanation: 1. Each ovum undergoes meiotic division just prior to being released from the graafian follicle. Each cell created by this meiosis has the same number of chromosomes, but the cytoplasm does not split equally. This causes a polar body to be produced along with a secondary oocyte. 2. Males begin spermatogenesis at puberty and continue throughout their life. Each sperm divides into four haploid cells. 3. Females are born with all the ova they will ever produce. The ova begin to be formed in early fetal life. One ovum is released each month during the reproductive life of a female, from menarche to menopause. 4. Primary spermatocytes contain 46 chromosomes (46XY). Each primary spermatocyte undergoes meiotic division into two haploid secondary spermatocytes (22X or 22Y).

A client at 18 weeks' gestation thinks she might have been exposed to a toxin at work that could affect fetal development and asks what organs might be affected at this point in the pregnancy. How should the nurse respond to this client? 1. "The brain is developing now and could be affected." 2. "Because you are in the second trimester, there is no danger." 3. "It's best to not worry about possible problems with your baby." 4. "The internal organs like the heart and lungs could be impacted."

Answer: 1 Explanation: 1. Maximum brain growth and myelination are occurring at this point in fetal development. 2. Although the greatest danger from teratogens is during the embryonic stage (the first 8 weeks of pregnancy), the fetus at 20 weeks is still vulnerable to exposure to teratogens. 3. Avoid telling clients not to worry. Doing so indicates to the client that you do not care about their concerns and will end effective communication. 4. The heart, lungs, and other internal organs form during the embryonic state, or the first 8 weeks of pregnancy. During their formation is when they are most likely to be affected by a teratogen.

The nurse is creating a teaching poster for pregnant mothers. Which description of fetal development should the nurse include? 1. Most organs are formed by 8 weeks after fertilization. 2. The embryonic stage is from fertilization until 5 months. 3. Four layers of cells form after the embryo is at the ball stage. 4. After fertilization, the cells only become larger for several weeks.

Answer: 1 Explanation: 1. Most organs are formed during the embryonic stage, which lasts from the 15th day after fertilization until the end of the 8th week after fertilization. This is also a critical period because major organs are being developed and teratogens introduced during this time can increase the risk of congenital abnormalities. 2. The embryonic stage begins on the 15th day after fertilization and ends at the completion of the 8th week after fertilization. 3. Three primary germ layers form from the ball of undifferentiated cells, the blastocyst: ectoderm, mesoderm, and endoderm. 4. After fertilization, the cells reproduce by mitosis, resulting in more cells, not larger cells.

A young woman claims that contraception is not needed because she avoids intercourse on the day of ovulation. How should the nurse instruct this client? 1. Sperm survive 48 to 72 hours in the female reproductive tract. 2. After ovulation, ova are considered fertile for about 72 to 96 hours.3. Sperm are believed to be healthy and highly fertile for at least 5 days. 4. Refraining from intercourse on the day of ovulation will effectively prevent pregnancy.

Answer: 1 Explanation: 1. Sperm survive 48 to 72 hours in the female reproductive tract. 2. Ova are considered fertile for about 12 to 24 hours after ovulation. 3. Sperm are believed to be most fertile for the first 24 hours following entry into the female reproductive tract. 4. Because sperm survive 48 to 72 hours in the female reproductive tract, avoidance of intercourse for 24 hours will not reliably prevent pregnancy from occurring.

The nurse is preparing a presentation about causes of fetal organ malformation in the first trimester. What prenatal influences on the intrauterine environment should be included in this teaching? Select all that apply. 1. The use of drugs 2. Maternal nutrition 3. The use of saunas or hot tubs 4. Age of the mother at conception 5. The quality of the sperm or ovum

Answer: 1, 2, 3 Explanation: 1. Many drugs can have teratogenic effects. 2. Maternal nutrition, if deficient, can cause damage to the fetus. Vitamins and folic acid taken prior to and during the pregnancy can have beneficial effects.3. The use of saunas or hot tubs is associated with maternal hyperthermia and neural tube defects. 4. A maternal age of 35 or older is associated with genetic defects that occur at conception, not with first-trimester organ malformation. 5. The quality of the sperm or ovum can affect fertility but not organ formation.

The nurse is reviewing the structures of the developing fetus with a group of pregnant clients. What should the nurse emphasize about the function of the placenta? Select all that apply. 1. It produces hormones. 2. It produces glycogen, cholesterol, and fatty acids. 3. It maintains fetal respiration, nutrition, and excretion. 4. It provides a circulatory pathway from the chorionic villi to the embryo. 5. It contains a specialized mucoid connective tissue known as Wharton jelly

Answer: 1, 2, 3 Explanation: 1. The placenta produces human chorionic gonadotropin (hCG); human placental lactogen (hPL), also referred to as human chorionic somatomammotropin (hCS); relaxin; inhibin; and estrogen and progesterone. 2. The placenta produces glycogen, cholesterol, and fatty acids continuously for fetal use and hormone production. 3. The placental functions include fetal respiration, nutrition, and excretion. To carry out these functions, the placenta is involved in metabolic and transfer activities. 4. The umbilical cord provides a circulatory pathway from the chorionic villi to the embryo. 5. The umbilical cord contains a specialized mucoid connective tissue known as Wharton jelly, which prevents compression of the umbilical cord in utero.

The nurse is explaining the difference between meiosis and mitosis. Which statements should the nurse include? Select all that apply. 1. Mitosis occurs in most of the cells of the body. 2. Meiotic division leads to cells that halve the original genetic material. 3. Meiosis is the division of a cell into two exact copies of the original cell. 4. Meiosis is the process by which gametes, or the sperm and ova, are formed. 5. Mitosis is splitting one cell into two, each with half the chromosomes of the original cell.

Answer: 1, 2, 4 Explanation: 1. Mitosis is how the majority of cells reproduce so that the new cells have the same structure and function as the original. Meiosis only occurs in gametes. 2. Meiosis creates two cells that have half of the chromosomes of the original cell. 3. Meiosis creates two cells that have half of the chromosomes of the original cell. 4. Both sperm and ova are created through meiosis. 5. Mitosis creates two cells that are exact copies of the original cell.

The nurse instructs a client about conception and fetal development. Which client statement indicates understanding about transportation time of the zygote through the fallopian tube and into the cavity of the uterus? 1. "It will take 8 days for the egg to reach the uterus." 2. "It will take at least 3 days for the egg to reach the uterus." 3. "It will take 18 hours for the fertilized egg to implant in the uterus." 4. "It will only take 12 hours for the egg to go through the fallopian tube."

Answer: 2 Explanation: 1. "It will take 8 days for the egg to reach the uterus" is an incorrect interpretation of the information on conception. 2. It takes at least 3 days for the egg to reach the uterus. 3. "It will take 18 hours for the fertilized egg to implant in the uterus" is an incorrect interpretation of the information on conception. 4. "It will only take 12 hours for the egg to go through the fallopian tube" is an incorrect interpretation of the information on conception.

The nurse is caring for a client who is pregnant with twins. Which statement indicates the client needs additional information? 1. "It is rare for twins to both be within the same amniotic sac." 2. "Because both of my twins are boys, I know that they are identical." 3. "If I have one boy and one girl, I will know they came from two eggs." 4. "If my twins came from one fertilized egg that split, they are identical."

Answer: 2 Explanation: 1. Monoamnionic-monochorionic twins are very rare and occur as a result of the zygote splitting 7 or more days after fertilization. 2. Not all same-sex twins are identical or monozygotic, because fraternal, or dizygotic, twins can be the same gender or different genders. 3. The only way to have twins of different genders is if they came from two separate fertilized ova. Monozygotic twins are identical and are the same gender. 4. When the zygote splits, identical twins share the same genotype result.

The nurse is conducting an early pregnancy class for a group of pregnant women. Which statement indicates a need for further education about the placenta? 1. "It develops and grows larger until about 20 weeks' gestation." 2. "It floats in the amniotic sac and filters waste products from the fetus." 3. "It creates hormones and enzymes that are necessary during pregnancy." 4. "It ages and becomes less permeable during the last month of pregnancy."

Answer: 2 Explanation: 1. The chorionic villi of the placenta become more differentiated with time. The placenta grows in size until about 20 weeks. After this point, the placenta thickens but does not increase in size. 2. The placenta is attached to the uterine wall, and does not float in the amniotic sac. One function of the placenta is to filter metabolic waste products from the baby's blood so that they can be excreted by the mother. 3. The placenta creates glycogen, cholesterol, hormones such as human chorionic gonadotropin (hCG), and enzymes such as sulfatase and insulinase. 4. The placenta is designed to last for 40 weeks, the average length of human gestation. The permeability to nutrients and oxygen begins to decrease starting at about 36 weeks as a part of the aging of the placenta.

A client who has experienced a fetal death in utero at 20 weeks asks what her baby will look like when it is delivered. How should the nurse respond to this client? 1. "The genitals of the baby will be ambiguous." 2. "Your baby will be covered in fine hair called lanugo." 3. "Your child will have arm and leg buds, but not fully formed limbs." 4. "A white, cheesy substance called vernix caseosa will be on the skin."

Answer: 2 Explanation: 1. The genitals are apparent by 12 weeks after fertilization. This fetus would have had specifically male or female genitals 8 weeks ago. 2. Downy fine hair called lanugo covers a 20-week fetus. 3. Limb buds have developed by 35 days postfertilization. At 20 weeks, the fetus will have well-developed well-differentiated arms and legs. 4. Vernix caseosa forms at about 24 weeks. This fetus is only 20 weeks and will not have vernix.

The nurse is preparing information about reproduction for high school students. What should the nurse include about the production of sperm? Select all that apply. 1. Diploid cells are formed. 2. Sperm cells develop through meiotic division. 3. Four spermatids are formed during the second meiotic division. 4. Spermatocytes contain either a double-structured X or Y sex chromosome. 5. Two secondary spermatocytes contain 22 double-structured autosomal chromosomes.

Answer: 2, 3, 4, 5 Explanation: 1. The formation of diploid cells occurs during mitosis. 2. Meiosis occurs during gametogenesis, the process by which sperm are produced. 3. During the second meiotic division, they divide to form four spermatids, each with the haploid number of chromosomes. 4. Spermatocytes contain either a double-structured X sex chromosome or a double- structured Y sex chromosome. 5. During the first meiotic division, the spermatogonium replicates and forms two cells called secondary spermatocytes, each of which contains 22 double-structured autosomal chromosomes.

A pregnant client who restricted the intake of fat, protein, and sugar to prevent a large weight gain delivers a small-for-gestational-age fetus. What long-term health problems is this child at risk for developing as an adult? Select all that apply. 1. Arthritis 2. Diabetes 3. Hypertension 4. Cystic fibrosis 5. Coronary heart disease

Answer: 2, 3, 5 Explanation: 1. Arthritis is not specifically linked to nutritional deficiencies in utero. 2. Poor maternal nutrition may also predispose babies who were small or disproportionate at birth to the development of adult diabetes. 3. Poor maternal nutrition may also predispose babies who were small or disproportionate at birth to the development of adult hypertension. 4. Cystic fibrosis is a genetic disease seen in pediatric clients. 5. Poor maternal nutrition may also predispose babies who were small or disproportionate at birth to the development of adult coronary heart disease.

Which statement by a client pregnant with twins would indicate that teaching was effective? 1. "Identical twins can be the same or different sex." 2. "Identical twins occur more frequently than fraternal twins." 3. "Congenital abnormalities are more prevalent in identical twins." 4. "Because of their birth relationship, fraternal twins are more similar to each other than if they had been born singly."

Answer: 3 Explanation: 1. Identical or monozygotic twins have identical chromosomal structures and therefore are always the same sex. 2. Dizygotic, or fraternal, twins occur more frequently than do monozygotic twins. 3. Due to variations in the timing of the splitting of the embryo, congenital abnormalities are more common in monozygotic twins. 4. Fraternal twins are not more similar to each other than if they had been born singly.

At her first prenatal visit, the client states, "I'm 5 weeks pregnant now and I would like to hear my baby's heartbeat today." How should the nurse respond? 1. Anticipate that the client will be scheduled for Doppler ultrasound. 2. Prepare to assist with auscultation of the fetal heartbeat using a fetoscope. 3 Explain to the client that the fetal heartbeat is not yet detectable at 5 weeks' gestation. 4. Explain to the client that the fetal heart does not begin to beat until approximately 7 weeks' gestation.

Answer: 3 Explanation:1. Generally, fetal heart tones cannot be heard until approximately the 8th week of pregnancy by ultrasound Doppler device. 2. Fetal heart tones can be identified through use of a fetoscope at approximately the 20th week of pregnancy. 3. While the tubular heart begins to form during the 3rd week, fetal heart tones generally are not detectable until at least 7 weeks' gestation. 4. The fetal heart begins to beat by the 4th week of gestation.

If only a small volume of sperm is discharged into the vagina, an insufficient amount of enzymes might be released when sperm encounters the ovum. What would be the result for pregnancy? 1. The block to polyspermy (cortical reaction) would not occur. 2. The fertilized ovum would be unable to implant in the uterus. 3. Sperm would be unable to penetrate the zona pellucida of the ovum. 4. Peristalsis of the fallopian tube would decrease, making it difficult for the ovum to enter the uterus.

Answer: 3 Explanation:1. The answer choice of the block to polyspermy (cortical reaction) not occurring is incorrect because it is mediated by release of materials from cortical granules below the ovum's surface and not the result of low sperm count. 2. With a low sperm count it is unlikely that the ovum would be fertilized. 3. Sperm would be unable to penetrate the zona pellucida of the ovum because it takes hundreds of acrosomes (the result of the acrosomal reaction) to rupture and release enough hyaluronic acid to clear the way for a single sperm to penetrate the ovum's zona pellucida successfully. 4. "Peristalsis of the fallopian tube would decrease, making it difficult for the ovum to enter the uterus" is an incorrect statement.

The nurse is reviewing the embryonic primary germ layers with a group of students. Which structures should the nurse identify as being formed from the mesoderm? Select all that apply. 1. Nails 2. Liver 3. Spleen 4. Muscles 5. Skeleton

Answer: 3, 4, 5 Explanation: 1. The nails originate from the ectoderm. 2. The liver originates from the endoderm. 3. The spleen originates from the mesoderm. 4. The muscles originate from the mesoderm. 5. The skeleton originates from the mesoderm.

A pregnant client asks about the differences between monozygotic and dizygotic twins. Which should the nurse include during this teaching? 1. Dizygotic twins share one placenta and one chorion. 2. Monozygotic twins are also referred to as "fraternal" twins. 3. Dizygotic twinning occurs less frequently than does monozygotic twinning. 4. Monozygotic twins originate from division of the fertilized ovum at different stages.

Answer: 4 Explanation: 1. Dizygotic twins each have a separate chorion and amnion. 2. Monozygotic twins are also referred to as "identical" twins. 3. Dizygotic twinning occurs more frequently than does monozygotic twinning. 4. Monozygotic twins originate from division of the fertilized ovum at different stages of early development.

After teaching a class about the female reproductive system, the nurse asks the attendees to describe the process of meiosis. Which student response suggests successful comprehension of the material? 1. "At the time of ovulation, the first meiotic division begins." 2. "At the time of puberty, the second meiotic division begins." 3. "Completion of the first meiotic division produces three polar bodies and one primary oocyte." 4. "Completion of the second meiotic division results in formation of three polar bodies and one ovum."

Answer: 4 Explanation: 1. The first meiotic division of oocytes begins before the female fetus is born. 2. The second meiotic division begins at the time of ovulation. 3. Completion of the first meiotic division produces one polar body and one secondary oocyte. 4. Completion of the second meiotic division produces three polar bodies and one ovum.