Ch. 8 & 9 Quiz Flashcards
What is the difference between genetics and genomics?
Genetics is the study of single genes and what effect they have. Genomics is a study of the function and interaction of all genes in a genome.
What percentage of miscarriage are estimated to chromosomal in origin?
62%
What is Tay-Sachs disease and what ethnic groups are more prone to it?
Overgrowth of fats. Jews, certain Canadians/Cajuns, Amish
What is Talassemia and what ethnic groups are more prone to it?
Blood hemoglobin disorder. Mediterranean, Middle Eastern, Central Asian
What type of disease is PKU and what ethnic groups are more prone to it?
Metabolic - can’t break down phenylalanine. Irish/Scottish, Scandinavian, Iceland, Polish
What type of disease is Cystic Fibrosis and what ethnic groups are more prone to it?
Chronic lung, thick mucous. Whites, Jews, Hispanics
What is the relevance of genetics to nursing?
Facilitates referral for specialized services.
Name 2 prenatal genetic tests.
CVS and aminocentesis.
Name 2 types of maternal genetic screenings.
AFP and triple marker.
What cancers can be screened for?
Breast & ovarian (Brca1-Brca2), Huntingtons & Alzeimers
What is the difference between recessive and dominant genes?
For a dominant trait to be expressed, it only takes 1 gene (remember we have 2 of each). For recessive trait to appear, both genes must support that trait.
What is the difference between genotype and phenotype?
Genotype is the genetic makeup of an organism, phenotype is the outward manifestations of the organisms genetics. (i.e., what it looks like)
What is a Karyotype?
It is a picture of a genetic profile.
What birth defects does folic acid prevent?
Neural tube defects.
What does congenital mean?
Present at birth.
What are teratogens?
Any agent that can impede or halt the development of an embryo or fetus. Drugs, chemicals, infections, radiation, diabetes and PKU in the mother.
What does homologous mean in regard to genetics?
It refers to chromosome pairs.
What is an autosome?
Non-sex chromosomes.
What are Loci?
Loci is plural for locus and is the specific location of a gene or DNA sequence on a chromosome.
What are alleles?
A single gene of the pair that forms a trait.
What is meant by homozygous? Heterozygous?
Having identical alleles for a single trait. Having different alleles for a single trait.
What abnormalities are a major cause of reproductive loss, congenital problems, and gynecologic disorders? Name 2.
Chromosome abnormalities. Turners syndrome (monosamy x) and Klingenfelters syndrome (Trisomy xxy).
What is chromosome translocation and what causes it? What syndrome?
Exchange of material between chromosomes. Caused by drugs/viruses/radiation. Cri du chat.
Name some uni-factorial defects.
Marfran’s, Treacher Collins, Dwarfism.
What is the difference between autosomal dominant and autosomal recessive?
In an autosomal dominant, it only takes 1 defective gene to produce the defect, in recessive it takes 2.
Which type of defect inheritance is more severe in males?
X-linked dominant inheritance. X-linked means it is on the X chromosome. Females transmit to offspring 50% of the time.
What is a multifactorial method of transmission? Give examples.
Most common. Combination of genetic and environmental factors. Cleft lip/palate, neural tube defects, heart, pyloric stenosis.
When does implantation of an egg usually occur?
6 days after fertilization.
What are the time frames for pre-embryonic, embryonic, and fetal stages?
Through 15th day, day 15-8 weeks (40 days), 9th week until birth.
Which fetal stage is most critical?
Embryonic.
Which germ layer forms the yolk sac of a 3 week old embryo?
Endoderm.
What attaches the embryo to the uterus?
Chorionic villi.
On average, how long is a pregnancy?
10 lunar or 9 calendar months. 40 weeks.
How many veins & arteries are in the umbilical cord?
1 vein and 2 arteries.
When is the placenta complete?
By 12 weeks.
What does the placenta do?
Provides metabolic exchange between the mother and fetus.
What is detected in maternal serum 8-10 days after fertilization? What does it do?
hCG. Preserves the corpus luteum which ensures supply of estrogen and progesterone to maintain the pregnancy until placenta can take over.
What do progesterone and estrogen do during pregnacy?
Progesterone maintains the endometrium. Estrogen stimulates uterine growth.
What position should be avoided when pregnant? Why?
Supine position. Can impede blood flow to the uterus (uterine perfusion), and lead to IUGR (intrauterine growth restriction) or SGA (small for gestational age).
An L/S ratio of _____ at _____ weeks shows fetal lung maturity.
2:1. 35 weeks. Lecithin starts at 21 weeks and increases after 24 weeks. Sphingomyelin is constant.
What is considered a normal fetal HR range?
120-160 bpm.
How does fetal hemoglobin levels concentration compare to mom’s? It’s oxygen carrying capacity?
50% higher. 20%-30% higher.
When is the hematopoietic system formed?
6 weeks.
When does the fetus start swallowing amniotic fluid?
20 weeks.
When is the GI system mature?
36 weeks.
When do the kidneys form? Function?
5 weeks. 9 weeks.
What forms a major part of the amniotic fluid volume?
Urine.
When can the baby hear sound?
24 weeks.
When are the eyes formed?
28 weeks.
When do muscles begin to contract?
7 weeks.
What is lanugo?
Fine protective hair that appears at about 5 months and usually falls off before birth.
What ethnic group has the largest incidence of dizygotic twins? Smallest?
African Americans. Asians.
Do you know the difference between monozygotic twins and dizygotic twins?
Mono - 1 egg splits. Di - 2 eggs are fertilized.
How long is gestation?
280 days after LMP or 266 days after conception.
When a zygote divides into 16 divisions it is called a _____?
Morula.
How long after ovulation does fertilization occur? Where?
24 hours. Fallopian tube.
How many births in the US are considered high risk?
1 in 8.
For the mother, high risk status arbitrarily extends through _____ (30 days after childbirth).
Puerperium. Complications usually resolve within 1 month of birth.
What is PPROM?
Preterm, premature rupture of membrane.
What is oligohydraminos? Polyhydraminos?
Lack of amniotic fluid. Too much amniotic fluid.
What are the 3 leading causes of Maternal mortality in the US?
Pregnancy induced hypertension, pulmonary embolism, hemorrhage.
What age factors are related to maternal deaths?
< 20 or > 35.
What other factors relate to elevated maternal deaths?
Lack of prenatal care, low education, unmarried, nonwhite (African Americans 3x higher).
What is the healthy birth goal?
< 3.3 deaths per 1,000,000 live births.
What is the AFP test used for?
Alpha Fetal Protein is used to detect neural tube, and other fetal defects.
What is BPP?
Biophysical profile. Test to determine if baby needs to be delivered ASAP. 2 points each for amniotic fluid volume, fetal movement, breathing, muscle tone, reactive NST. Score
What is amniocentesis used to detect?
Genetic disorders, lung maturity, hemolytic disease.
What is PUBS?
Percutaneous umbilical blood sampling. (Under ultrasound) Done 1-2cm from placental insertion point. 1-4mL of blood removed.
What is tested because it reflects the genetic makeup of the fetus?
Chorionic villi. Go in through vagina.
What test identifies Downs Syndrome 60% of the time?
Triple marker test.
