Essentials of Lifespan Development Ch 2

evolutionary psychology

emphasizes the importance of adaptation, reproduction, and survival of the fittest in shaping behavior

chromosomes

threadlike structures of DNA

Deoxyribonucleic acid

a complex molecule w/ a doubly helix shape that contains genetic info

genes

short segments of DNA; units of hereditary info composed of DNA. direct cells to reproduce themselves and manufacture the proteins that maintain life

mitosis

cellular reproduction in which the cell's nucleus duplicates itself with 2 new cells being formed, each containing the same DNA as the parent cell, arranged in the same 23 pairs of chromosomes

meiosis

a specialized form of cell division that occurs to form eggs and sperm (gametes)

genotype

a person's genetic heritage, the actual genetic material

phenotype

the way an individual's genotype is expressed in observed and measurable characteristics

Down Syndrome

a chromosomally transmitted form of intellectual disability, caused by the presence of an extra copy of chromosome 21

behavior genetics

field that seeks to discover the influence of heredity and environment on individual differences in human traits and development

twin study

study in which the behavioral similarity of identical twins is compared with the behavioral similarity of fraternal twins

epigenetic view

emphasizes that development is the result of an ongoing bidirectional interchange between heredity and environment

gene x environment interaction

interaction of a specified measured variation in DNA and a specified measured aspect of the environment

germinal period

period of prenatal development that takes place in the first 2 weeks after conception. Includes creation of the zygote, continued cell division, and the attachment of the zygote to the uterine wall

embryonic period

critical period 2-8 weeks after conception in which the rate of cell differentiation intensifies, support systems for the cells form, and organs appear. at 6 weeks: early formation of nervous system

organogenesis

organ formation that takes place in the first 2 months of prenatal development, during embryonic period

fetal period

2 MONTHS after conception and lasts about 7 months

neurons

nerve cells that handle info processing at the cellular level in the brain

teratogen

any agent that can potentially cause a birth defect or negatively alter cognitive and behavioral outcomes

fetal alcohol spectrum disorders

a cluster of abnormalities that appears in the offspring of mothers who drink heavily during pregnancy

natural childbirth

no drugs are given to relieve pain or assist in birth process, mother and partner are taught to use breathing methods and relaxation techniques during delivery

prepared childbirth

developed by Lamaze, includes a special breathing technique to control pushing in the final stages of labor and more detailed anatomy and physiology instruction

Apgar scale

a widely used assessment of the newborn's health at 1 and 5 min after birth

postpartum period

period after childbirth in which the mom adjusts, both physically and psychologically, to the process of child bearing. this period lasts for about 6 weeks or until her body has completed it's adjustment and returned to a nearly prepregnant state

embryo's endoderm

inner layer of cells which will be the digestive and respiratory systems

embryo's mesoderm

middle layer of cell's which will be circulatory system, bones, muscles, excretory system, and reproductive system

embryo's ectoderm

outer layer of cell's which will be nervous system, sensory receptors, and skin parts

Adaptability of evolved mechanisms

not all are adaptive in contemporary society ex: propensity to crave high caloric food- epidemic of obesity

Sources of variability

chromosomes on zygote are not exact copies of those in mother and father (crossing over and independent assortment)

mutated gene: permanently altered segment of DNA

Genotypes and Phenotypes

Genetic principle: Dominant and Recessive genes

one gene of a pair always exerts its effects, overriding the potential influence of the other gene

Genetic principle: Sex linked genes

When a mutated gene is carried on the X chromosome, the result is called X-linked inheritance

Genetic principle: Polygenic inheritance

Polygenically determined by the interaction of many different genes

Genetic principle: Gene-gene interaction

the interdependence of two or more genes in influencing characteristics, behavior, diseases, and development

Fragile X Syndrome

Abnormality in X chromosome can cause intellectual disability, learning disabilities, or short attention span: more common in males

Down Syndrome

an extra chromosome 21 causes mild to severe retardation and physical abnormalities: 1 in 1900 at age 20, 1 in 300 at 35, 1 in 30 at 45. 1 in 700 births in all

Gene linked abnormality: Diabetes stat

1 in 2500

Gene linked abnormality: defects in genes- some examples are...

Huntington's, Diabetes, Hemophilia, Cystic Fibrosis, PKU, Sickle cell anemia, Spina Bifida

behavior geneticists

study twins or adoptions, look at influences of heredity and environment

Passive genotype-environment correlations

occur bc biological parents, who are genetically related to a child, provide the rearing environment for the child (musically inclined parents create musical environments for their musically inclined kids)

Evocative genotype-environment correlations

occur bc a child's characteristics elicit certain types of environments

Active (niche-picking) genotype-environment correlations

occur when kids seek out environments they find compatible and stimulating

time of exposure, organ specificity, genetic susceptibility, dose effect

the 4 principles of teratogen effects

prescription and non prescription drugs, psychoactives, caffiene, alcohol, nicotine, cocaine, meth, marijuana, heroin

teratogens

Hazard to prenatal devel: incompatible blood types

if M and D have different Rh markers; baby could inherit Rh+ blood and M's Rh- blood could attack it w antibodies

maternal age, maternal diet and nutrition, maternal diseases, environmental hazards, emotional states in mother, paternal factors

Hazards to prenatal development

exposure to lead, radiation, certain pesticides and petrochemicals can cause sperm abnormalities, smoking during conception and throughout pregnancy, age is a factor as well

paternal factors

health and development issues; learning disabilities, adhd, breathing problems

consequences of low birth weight

low birth weight infants

less than 5 pounds at birth

preterm infants

born 3 or more weeks before full term pregnancy (35 or fewer weeks)

small for date infants

birth weight below normal when length of pregnancy is considered (under 90 % of other babies its gestational age)

extremely preterm infant

gestational age less than 28 weeks

very preterm infant

gestational age 28- 32 weeks (less than 33)

involution

process by which the uterus returns to its prepregnant state goes from 2-3 pounds to 2 to 3.5 ounces