addresses the functions and interactions of allthe genes in an organism
Two key findingsfrom the Human Genome Project arethat all humans are
99.9% identical at the DNA level and that 30,000to 40,000 genes make up the human genome.
multifactorial inheritance
Most common congenital malformations, such as cleft lip and palate, result from multifactorial inheritance, a combination of genetic and environmental factors.
Mitosis
is the process of somatic cell division in which a single cell divides, and both new cells have the same number of chromosomes as the single cell.
Meiosis
is the process in which germ cells divide and decrease their chromosomal numbers by one-half.
Conception is
part of a sequential process including gamete formation, ovulation, union of the gametes, and implantation in the uterus.
Fertilizationoccurs in
the ampulla of the uterine tube within 24 hours of ovulation.
Intrauterine development is divided into three stages:
preembryonic (from conception until day 14)
embryonic (from day 15 until 8 weeks after conception)
fetal (from 9 weeks until the end of the pregnancy).
During the embryonicstage...
organ systems and external features develop.
During the fetalstage...
structures and functions are refined
During the A stage, developing areas with rapid cell division are vulnerable to malformation by B. The fetus is less vulnerable to teratogens, except for those affecting C.
A) embryonic
B) environmental teratogens
C) central nervous system function
Cystic fibrosis is this type of genetic disease...
an autosomal recessive genetic disorder that affects most critically the lungs, and also the pancreas, liver, and intestine. It is characterized by abnormal transport of chloride and sodium across an epithelium, leading to thick, viscous secretions.
X-linked recessive inheritance occurs when the abnormal gene is carried on the X chromosome, such as in A or B.
A) hemophilia
B) Duchenne muscular dystrophy.
Disorders in which a single gene controls the particular trait describe the A inheritance
A) unifactorial
Ig "A" is not produced or passes in utero, but is acquired by B.
A) IgM
B) colostrum
Fetus produces Ig "A" by B
A) IgM
B) end of first trimester
Imunoglobin that crosses the placenta
IgG - passive acquired immunity to specific bacterial toxins
Biggest difference in development
4th week to 8th week of embryo stage (weeks 3-8), fetus starts at week 9
Placenta also functions as a A producing B necessary to maintain pregnancy. They are:
A) endocrin gland
B) 4 hormones
hCH human Chorionic Hormone - detectable by 7-10 days after conception and the basis for pregancy tests
estrogen
progesterone
human chorionic somatomammotropin (hCS)
Anautosomal recessive inheritance disorder occurs when both genes of the pair areabnormal, such as in A, B or C.
A) phenylketonuria
B) sickle cell anemia.
C) CF
Autosomal dominant inheritance occurs when the abnormal gene for the trait is expressed,even when the other member of the pair is normal, such as in A and B.
A) Huntington’sdisease
B) Marfan syndrome
What best describes the pattern of genetic transmission known as autosomal recessive inheritance?
C. Disorders in which both genes of a pair must be abnormal for the disorder to be expressed
Autosomal dominant inheritance occurs when the abnormal gene for the trait is expressed, even when the other member of the pair is normal, such as in Huntington’s disease or Marfan syndrome. An autosomal recessive inheritance disorder occurs when both genes of the pair are abnormal, such as in phenylketonuria or sickle cell anemia. Disorders in which a single gene controls the particular trait describe the unifactorial inheritance. X-linked recessive inheritance occurs when the abnormal gene is carried on the X chromosome, such as in hemophilia or Duchenne muscular dystrophy.
The student nurse is giving a presentation about milestones in embryonic development. Which information should he or she include?
C. At 20 weeks of age, the vernix caseosa and lanugo appear.
The primary lung and urethral buds appear at 6 weeks of gestation. The vagina is open or the testes are in position for descent into the scrotum at 16 weeks. Two milestones that occur at 20 weeks are the appearance of vernix caseosa and lanugo. The appearance of smooth skin occurs at 28 weeks, and subcutaneous fat begins to collect at 30 to 31 weeks.
With regard to chromosome abnormalities, nurses should be aware that:
A. Abnormalities of number are the leading cause of pregnancy loss.
Chromosome abnormalities occur in A of newborns.
fewer than 1%
A is an abnormality of number that also is the leading genetic cause of B.
A) Aneuploidy
B) mental retardation
"A" is the most common form of trisomal abnormality, an abnormality of chromosome number B
A) Down syndrome
B) 47 chromosomes
"A" is an abnormality of chromosome structure that often has serious clinical effects.
A) Unbalanced translocation
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. Testing to determine the chance of cystic fibrosis occurring again is known as:
D. Recurrence risk.
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 A risk test.
A) occurrence
"A" testing is used to clarify the genetic status of an asymptomatic family member.
A) Predictive
"A" testing differs from presymptomatic testing in that a positive result does not indicate 100% risk of a condition developing.
A) Predisposition
Genetic predisposition is a genetic affectation which influences the phenotype of an individual organism within a species or population but by definition that phenotype can also be modified by the environmental conditions. In the rest of the population, conditions cannot have that effect
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?
B. 2:1
A couple has been counseled regarding genetic anomalies. They ask you, “What is karyotyping?” Your best response would be:
B. “Karyotyping will provide information about the gender of the baby and the number and structure of the chromosomes.”
"A" reveals lung maturity.
A) L/S or lecithin to sphingomyelin
lecithin is the surfactant. It isincreasing, while sphingomyelin rtemains constant.
The most basic information a maternity nurse should know 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.
D. Implantation in the endometrium occurs 6 to 10 days after conception.
Ova are considered fertile for about A after ovulation.
A) 24 hours
Sperm remain viable in the woman’s reproductive system for an average of A.
A) 2 to 3 days
Penetration of the ovum by the sperm is called A. Conception occurs when the B.
A) fertilization
B) zygote, the first cell of the new individual, is formed.
Which congenital malformations result from multifactorial inheritance? Choose all that apply.
A. Cleft lip
B. Congenital heart disease
C. Cri du chat syndrome
D. Anencephaly
E. Pyloric stenosis
A, B, D, E
Cleft lip is associated with A.
A) multifactorial inheritance.
Congenital heart disease is associated with A
A) multifactorial inheritance.
Cri du chat syndrome is related to a A.
A) chromosome deletion
Anencephaly is associated with A.
A) multifactorial inheritance
Pyloric stenosis is associated with A.
A) multifactorial inheritance
Amniocentesis (also referred to as amniotic fluid test or AFT) is a medical procedure used in prenatal diagnosis of chromosomal abnormalities and fetal infections usually at ...
14-16 weeks
Chorionic villus sampling (CVS)
is a form of prenatal diagnosis to determine chromosomal or genetic disorders in the fetus. It entails sampling of the chorionic villus (placental tissue) and testing it for chromosomal abnormalities, usually with FISH or PCR. CVS usually takes place at 10–12 weeks' gestation, earlier than amniocentesis or percutaneous umbilical cord blood sampling. It is the preferred technique before 15 weeks.
achondraplasia is
dwarfism
A monosomony is A and B
A) 45 chromosomes
B) never survives
A% of misscarriages and B% of stilbirths are caused by chromosomal abnormalities
A) 62%
B) 10%
Pairs of autosomes
22
# of genetically inheritable conditions
1672
Lanugo
very fine hairs that appear at 12 weeks and cover entire body by 20 weeks
chorion
is one of the membranes that exist during pregnancy between the developing fetus and mother
Fetus
in utero developing human from 9 weeks to birth
Embryo
Conceptus from day 15 to about 8 weeks
PKU kids
cannot consume any phenulalinine
CF kids may have
salty sweat
The ability of the fetus to survive outside the uterus is called A.
A) viability
In the past the earliest age at which fetal survival could be expected was 28 weeks after conception. With modern technology and advances in maternal and neonatal care, viability is now possible approximately 20 weeks after conception (22 weeks since the LMP, fetal weight of 500 g or more). The limitations on survival are based on CNS function and oxygenation capability of the lungs.
