Chapter 2 : Psychology 2070

DNA molecules

contain genetic code; make up genes

genes

segments of DNA that encode specific traits/characteristics

alleles

different versions of genes

46 chromosomes

collections of genes

zygote

new cell formed by process of conception

multiple births

rare in humans

identical twins

single fertilized egg splits into 2 individuals

fraternal twins

2 eggs fertilized by 2 sperm cells

sex chromosomes

determine sex of developing individual

the sex chromosomes are called either X or Y

androgens

cause male genitals to develop

gonads

testes in males and ovaries in females

dominant trait

“wins” against recessive trait

recessive trait

must inherit copies from both parents to be expressed

x-linked genes

located only on x chromosome / means males are more susceptible to x-linked disorders; no other x chromosome​​

hemophilia

blood disorder produced by X-linked genes

homozygous

same info from both parents​

heterozygous

different info from both parents​

genotype

inherited genes

phenotype

expression of genes

polygenic Inheritance ​

skin and eye color​

Multi-factorial Inheritance

• 2 kids – same genetic heritance for height.​

• Poor nutrition, sickness = shorter​

• Well-fed, healthy = taller

reaction range

range of possibilities set up bygenes; environment determines final outcome

autosomal disorders

are caused by genes located on the autosomes / most recessive disorders are diagnosed in infancy or early childhood.

phenylketonuria (PKU)​ (autosomal disorders)

may lead to developmental disorders as toxins build up in baby’s brain​​

huntington’s disease​ (autosomal disorders)

brain deterioration – psychological and motor functions

tay-sachs disease​ (autosomal disorders)

fatty proteins cause problems w/vision, hearing,movement, mental dev (no treatment, infantile form always fatal)

sickle-cell anemia (autosomal disorders)

red blood cells are sticky and stiff; can block blood flow

sex-linked disorders

 genes that cause sex-linked disorders are found on the X and Y chromosomes.

fragile - x syndrome

“fragile” or damaged spot on X chromosome​

chromosomal errors

a variety of problems can be caused when a child has too many or too few chromosomes

trisomies

condition in which a child has three copies of a specific autosome

trisomy 21 / down syndrome

3 chromosomes at the 21st pair​

sex-chromosome anomalies

• klinefelter syndrome - males w/extra X chromosome - XXY​

• turner syndrome - need hormones at puberty to develop breasts,menstruate​

• XYY - boys with an extra Y chromosome (XYY) are taller than average and have large teeth. 

Genetic Counseling

helping people cope w/issues caused byinherited disorders​

Ultrasound sonography

• high-frequency sound waves used to produce image of embryo​

• Can detect large abnormalities​

Chorionic villus sampling

samples of hairlike materialsurrounding embryo; can be through cervix or abdominal wall​

Amniocentesis

• needle that gathers small sample of fetalcells​

• Slight risks associated with 2 and 3​

fertilization

• sperm and ovum unite in fallopian tubes​

• Risky journey back to uterus – 50-60% don’t make it.​

ectopic pregancy

fertilized egg implants in fallopian tubes. Must be removed​

stages of prenatal development - 1. germinal stage

first two weeks of gestation, from conception to implantation, constitute the germinal stage

Blastocyst

hollow sphere of cells w/2 layers​

implantation

buried in uterine wall​

placenta

allows oxygen, nutrients, etc., to passb/w baby and mother​

umbilical cord

connects individual to placenta

yolk sac

produces blood cells until individual’scells take over​

amnion

fluid-filled sac that contains individual​

stages of prenatal development - 2. embryonic stage

begins when implantation is complete, at about the end of the second week of pregnancy

ectoderm

outer layer; skin, nervoussystem​

endoderm

inner layer; viscera​

mesoderm

middle layer; muscle and bone​

neural tube

will give rise to the brain and spinal cord

stages of prenatal development - 3. embryonic stage

Final stage

neural proliferation

increase in paceof neural dev​

infertility

inability to conceive after 12-18 months of trying

causes of infertility…

• age of parents

• previous use of birth control, drugs, cigs, STIS

• low sperm count

• failure to release egg during ovulation - hormonal imbalance, damage, stress

• anatomical issues

artificial insemination

sperm placed in vagina by doctor ($1,000/attempt)

in vitro fertilization

eggs are removed and combined w/sperm in lab ($12,000 - $20,000/attempt)

teratogens (prenatal env)

(greek - monster making) environmental agent that produces or increases risk of birth defects

mothers diet

maternal malnutrition puts both the mother’s and the fetus’s health at risk

mother’s age

too young or too old increases risks / strain on body; increased issues getting pregnant w/age; increased risks of birth defects w/age

illnesses

rubella/german disease (blindness, deafness, heart defects, and brain abnormalities) or HIV(virus may cross the placenta and enter the fetus’s bloodstream, or the infant may contract the virus in the birth canal)

prescription and over the counter drugs

• just because a medication is prescribed or available over the counter does NOT mean it is safe to take while pregnant

• consult your doctor about ALL medications

illegal drugs

• marijuana - risk of learning disabilities if Mom smoked heavily

• heroin

• tobacco

• alcohol

FASD

small size overall, smaller brains, heart defects, facial abnormalities, dev delays (most common non-inherited form of dev delays in US)

FAE

some, tho not all problems associated w/mother drinking smaller amounts of alcohol during pregnancy

father’s affect the prenatal environment

• secondhand smoke can affect mother’s health

• alcohol and illegal drugs can lead to chromosomal damage at conception

• stress may produce an unhealthy environment for mother

• sperm damage may result from exposure to environmental toxins in workplace

labor (stage 1) - dilation

opening of the cervix

labor (stage 1) - effacement

thinning/flattening of the cervix

active phase

egins when the cervix is three to four centimeters dilated and continues until dilation reaches about eight centimeters

transition

last 2 cm of cervical dilation. most painful. (mom may vomit and shake uncontrollably - upsetting, but expected)

stage 2 - episiotomy

incision in pernineum to increase opening of vagina

stage 3 afterbirth

umbilical cord and placenta are expelled

lamaze birthing techniques

learn how to deal positively w/pain and to relax at onset of a contraction

bradley method

“husband-coached childbirth“ (childbirth should be as natural as possible and involves NO medication or medical interventions)

hypnobirthing

involves a self-hypnosis during delivery produces peace and calm and reduces pain

water birthing

giving birth in pool of water / weightlessness is thought to reduce discomfort

birth attendants (obstetricians)

MDs w/special training in labor delivery

certified nurse - midwives - registered nurses

special birth training

certified midwives

special training, but not nurses

doulas

emotional support; no medical training

drugs during delivery (epidural aneshesia)

numb below waist

walking epidural

smaller needle; continuous delivery of medication; more movement

preterm infants (birth complications)

born less than 38 weeks gestation; risk of illness, death

low birth weight infants (birth complications)

less than 5.5 pounds; usually early

small-for-gestational age infants (birth complications)

weight 90%or less of average of infants of same gestational age

respiratory distress syndromes (birth complications)

lack surfactant that keeps air sacs fully inflated

very-low-birthweight infants (birth complications)

weight less than 2.23 lbs, or have gestated less than 30 weeks

age of viability (birth complications)

can live outside womb; earliest is about 22 weeks (less than 50/50 chance at 25 weeks)

causes of preterm and low birthweight

about ½ - unknown, multiple births, young mothers (under 15), too closely spaced births, general health and nutrition of mom

postmature infants

not born 2 weeks after due date

postmature infants problems

fetus is too big, birth complications placenta starts to fail, may inhale feces,

cesarean delivery

surgical birth

why to have a c-section

breech or transverse presentation, fetal distress, labor fails to progress

stillbirth

delivery of infant who has died

infant mortality

death of infant in first year of life

impact

may experience prolonged grief / loss often minimized by others / don’t say things like ‘“You can have another baby“