Lecture 2 Flashcards
Zygote
The first cell that is created when a sperm pushes through the membrane of the ovum
Humans have __k genes
25k genes
the environment can turn genes __ and ___-genes collaborate w/ __ and w/ ______ in/out of the ___
on and off!Genes collaborate with each other and with nongenetic factors in and outside of body
Meiosis process____ once, ____ twice, creating _____-each cell contains…
-duplicates once, divides twice creating 4 cells-each cell contains 23 unpaired chromosomes, half of genetic material of parent
Likelihood of giving birth to twins? (%)
less than 3%
monozygotic twinsdizygotic twins
-monozygotic (single fertilized ovum divides)-dizygotic (2 ova fertilized by 2 diff sperm around same time)
2 reasons probability of multiple births has increased
-increased use of fertility drugs-increased due to increase age in birth mothers
Genoytep
person’s actual genetic material
Phenotypedef._____ of ph can be…
Observable and measurable characteristics of an individual.range of phenotypes can be expressed for each genotype
Dominant-recessive genes
.Dominant gene overrides the expression of the recessive gene.Recessive gene exerts its influence only if both genes in the pair are recessive
Sex-linked genes.def.x-linked inheritance?.what is it due to?
-usually do with female/male characterisitcs, but X-linked inheritance females usually carriers (cause have 2 X alleles and one dominant) but men have only one X so a recessive gene will exhibit-X-linked inheritance results when a mutated gene is carried on the X chromosome
Phenylketonuria (PKU).kind of disorder?.child cannot use…?.what can build to ____ levels.produced by a?
Inherited disorderChild cannot use phenylalanine (essential amino acid in proteins found in foods)If untreated phenylalanine can build to toxic levels Produced by a single allele (pair of genes)
Polygenic inheritance.def.most characteristics determined by….genes vary in their…
when multiple gene pairs are responsible for the production of a trait. Most human characteristics are determined by interaction of several genesGenes also vary in their REACTION RANGE
When can development deviate from the norm (affected by genetics).genes become….spontaneous….what factors infl?
-Genes become physically damaged-Spontaneous mutations occur-Environmental factors influence genes
CHROMOSOMAL Disorders.Down Syndrome.Klinefelter Syndrome.Fragile X syndrome.Turner syndromXYY syndrome
.Down Syndrome(extra chromosome, intellectual disability & physical abnormalities).Klinefelter Syndrome(extra X chromosome, physical abnormalities).Fragile X syndrome(abnormality in X chromosome, intellectual & cog. disabilities).Turner syndrome(missing X chromosome in females, intellectual disability and sexual underdevelopment).XYY syndrome(extra Y chromosome above-average height)
Genetic Disorders
Cystic fibrosisDiabetesHemopheliaHuntington’s DiseasePhenylketonuriaSickle-cell anemiaSpina bifidaTay-Sachs disease
Ultrasound Sonographydef.the ___ and ____ of unborn baby…
-high-frequency sound waves scan the womb to produce an image of the unborn baby. -The size and shape of the unborn baby can be assessed
Chorionic villus sampling (CVS).def.used to?
test that involves taking samples of material that surrounds the embryo.. used to detect genetic defects
Amniocentesis
identifying genetic defects by examining a small sample of fetal cells obtained by inserting a needle into the amniotic fluid.
Behavior genetics
Investigates the influence of heredity and environment on individual differences in human traits and development
Multifactorial transmission
traits are determined by a combination of genetic and environmental factors (genotype provides a range within which phenotype is expressed)
Adoption study.def.may also compare…
Seek to discover whether adopted children’s behavior and psychological characteristics are more like adoptive or biological parents. May also compare adoptive and biological siblings
Heredity-environment correlations.def.as child ages….some environments can?
Individuals’ genes may influence environments to which they are exposed. As child ages, experiences extend beyond family.Some environments can mute or strengthen genetic traits
Passive genotype-environment correlations
Biological parents, who are genetically related to child, provide rearing environment
Evocative genotype-environment correlations
Child’s characteristics elicit certain types of characteristics
Active (niche-picking) genotype-environment correlations
When children seek out environments they find compatible and stimulating
Shared environmental experiencesVS.Nonshared environmental experiences
Siblings’ common experiencesVSChild’s own unique experiences, both within and outside of family, not shared by sibling
Epigenetic view
Development is the result of an ongoing, bidirectional interchange between heredity and environment
Genetic factors strongly linked to which personality traits?
NeuroticismExtroversion
Genetic factors are also linked to many psychological disorders including…
SchizophreniaMajor depressionAlcoholismAutismADHD
Conception
When a single sperm cell unites with an ovum in a process called fertilization
Prenatal Dev..lasts for.begins/ends with.divided into?
Lasts for approximately 266 daysBeginning with fertilization and ending with birthFurther divided into three periods
Germinal period
First 2 weeks after conception
Embryonic Period
From 2-8 weeks after conception
Fetal Period
Lasts about 8 weeks until birth
Infertility.def, %?.among men?
.inability to conceive after 12-18 months of trying, ~15% couples.men: too few sperm.women: failure to release egg
Infertility treatments
Drugs or surgeryArtificial inseminationIn vitro fertilization
Miscarriage.def.% of pregnancies?
.spontaneous abortion, when the embryo detaches from the wall of the uterus and is expelled before the child can survive outside the womb.15-20% in first several months
Teratogen.def.severity depends on?
Any environmental agent that can potentially cause a birth defect or negatively alter cognitive or behavioral outcomes.severity depends on: dosage, genetic susceptibility, time of exposure
Labour (266 days after conception).CRH triggers?.when oxytocin levels hi?.when birth imminent?
.CRH triggers release of oxytocin. When oxytocin levels are sufficiently high, the uterus begins periodic contractions. When birth is imminent: uterus contracts intermittently
Stages of birth.Beginning of uterine contractions… (min, cervix)
Beginning of uterine contractions:.8-10 minutes apart.Cervix stretches and opens to 10 centimetersBaby begins to move through birth canal. Contractions come almost every minute.Mother bears down to push the baby outAfterbirth.Placenta, umbilical cord, and membranes detached and expelled
Apgar Scale.def.measures?
. Used to assess the health of newborns at one and five minutes after birth. Heart rate, respiratory effort, muscle tone, body color, and reflex irritability evaluated.want a 7/10
Bonding.in 1970s/80s argued that…but?other but?
.immediately after birth emotional/physical contact critical for healthy bond.empirical evidence lacking.but newborns do need touch/gentle massage shortly after to stimulate production of chemicals responsible for initiating growth
Obstetricians
physicians who specialize in delivering babies
Midwives.def.incr. demand….for pregnancies with…
.usually nurses specializing in childbirth.increasing demand but only 3% of woman ask for one.for pregnancies with no expected complications
Doula
provides emotional, psychological, and educational support during birth
Epidural anesthesia.def.50% of women choose…?.walking epidurals and dual spinal-epidurals can…
produces numbness from the waist down. Approximately 50% of Canadian women choose this option.Walking epidurals and dual spinal-epidurals can allow women to move more freely
newborn medical screening.def.# of tests varies by…
Newborns: are typically tested for a variety of genetic conditions and diseases. The number of tests varies by province
Preterm infants.def.avg newborn vs lo birth weight newborn.imp of remaining in hospital to gain add. weight?
.infants who are born before 37 weeks gestation (known as premature).3400g (avg) vs
If preterm infants are very premature and small, at risk of developing…
respiratory distress syndrome (RDS). As a result, they are often placed in incubators.
VERY-low-birth-weight infants.def (this OR that).significant danger of death b/c?
.Weigh less than 1250 grams OR (regardless of weight) have been in womb less than 30 weeks.Significant danger of death since their organ systems are immature
Postmature infants.def.y a problem? (2)
.infants still unborn 2 weeks after the due date.Blood supply from the placenta can become insufficient to nourish the fetus.baby gets too big to push out!!!
Caesarean delivery.def.% of moms.most often requested if?.sometimes used when?
baby is surgically removed from the uterus instead of being delivered through birth canal.25% of mothers.Most often requested when fetus shows distress or if blood flows from mother’s vagina during labor.Sometimes used when baby is in breech position
Stillbirth.def.freq?
.delivery of infant that is not alive.Occurs in fewer than 1/100 deliveries
Infant mortality
.death within 1st year of life.7/1000 live births.
Postpartum blues.def.without treatment, feelings…
.Feelings of anxiety, upset, or depression that come and go for several months following birth.Without treatment, feelings go away after a few weeks
Postpartum depression.def (what is it, what feelings/difficulties).may worsen w/o?
.Major depressive episode that occurs about 4 weeks after delivery.Strong feelings of sadness, anxiety, despair, trouble coping with daily tasks.May worsen without treatment
Newborn babies begin to…. as soon as exposed to?
Newborn babies begin to breath on their own as soon as they are exposed to air.
Newborn reflexes
SuckingSwallowingRootingCoughingSneezingBlinking
Newborn abilities.vision?.hearing?.touch/smell/taste?
.newborn vision poor, but can detect strong contrasts w/ environment and distinguish b/t diff colors.can hear and recognize sounds.touch, smell and taste all well developed
