psych 1101 quiz 2 modules 3,10,13,14

describing data

Measures of central tendency are single scores that represent a set of scores

mode

most frequently occurring score

mean

arithmetic average of scores

can be distorted by a few extreme scores

median

middle score in a distribution

50% above and 50% below

how to describe variation

range and standard deviation

range

• difference between the highest and lowest scores in a distribution

• A better way to describe variation

standard deviation

assess how much scores vary around the mean score 

normal curve

• Symmetrical, bell shaped

• Most (68%) scores are between 1 SD above and below

• Very common

samples results are trustworthy (reliable) when

• The sample is representative

• Your sample is large

statistical significance

• Is what we found

• Meaningful

• Not random

• True for population

• A number that results from an equation

genes

• Biochemical units of heredity that make up chromosomes

• When expressed, provides instructions to make proteins

• Genes made of DNA sequence (deoxyribonucleic acid)

• segments of DNA that contains instructions to make proteins the building blocks of life

how many genes do humans have

• 20000 genes

• Arranged along 46 chromosomes (23 pairs)

• Chromosome of every pair from each parent

order from smallest to largest (genes, DNA, chromosome)

genes, DNA, chromosomes

monogenic (single-gene) traits

some traits are primarily determined by single gene pair

allele

 pair of genes that affect the same trait

• All pairs of alleles constitute a person's genotype (individual biochemical makeup)

phenotype

How a trait is expressed (how it looks)

example of the gene for brown eyes is dominant

• We get one gene in each allele from each parents 

• BB- result in brown eyes, Bb- brown eyes, bB - brown eyes, bb blue eyes

• The genes (BB or Bb or bb) are the genotype

• Eye color is the phenotype

homozygous

same

heterozygous

different

if you have the recessive phenotype,

then we know your genotype

if you have the dominant phenotype,

then we do not know the genotype

What are some common, observable, inherited human genetic traits?"

side from eye color > ear lobe if they dangle or attach, roll your tongue, hair widow peak or no

recessive genes

• Impact is generally detrimental to the organism

• Most are not expressed

two kinds of genetic research

molecular and behavior genetics

molecular genetics

• the process of which genes are inherited

• How genes influence biology (creation of proteins)

• Need a "wet lab" to study

• Typically studied by physicians or psychiatrists

behavior genetics

•  result of genetic variation

• Study patterns of behavior and their linkages to genetic material

• Do not need a wet lab

• needs > people of known genetic relationships to each other (e.g. families or twins)

• Data of any kind

what are the two kinds of twins

monozygotic (identical) or dizygotic (DZ) fraternal

monozygotic (MZ) identical

 you need one sperm and one egg, cell divides

100% of these genes

If MZ are more similar, indicates a genetic effect

dizygotic (DZ) fraternal

two eggs and two sperms

50% of these genes on average

schema

cognitive structure that organizes information

assimilation

using existing schema for new information

example of schema

•  schema for dog with a little kid> funny, soft, four legs > dog

• Parents bring home cat but kid calls it a dog

accommodation

modifying way of thinking to better fit new information

sensorimotor stage

 birth to 18 months or 2 years, knowing by sensing or acting

pre operational stage

approximately by 2 to 7 years, concept formation, symbolic reasoning

stranger anxiety

• at 7 months, show fear around strangers that approach

• What does this mean? > can distinguish between familiar and unfamiliar people

• Memory is developing

habituation

 a decrease in responding with repeated stimulation

reflex and examples of them

• automatic set of coordinated behaviors

• Aids with survival

• Palmar grasp, plantar grasp (foot), moro/startle reflex, rooting reflex (turning towards cheek as it is touched), sucking reflex (infant feels something on palate, close and suck), Babinski reflex( toe spread out)

organogenesis

 organ develop during embryo

tetratogen

•  environmental agent such as virus or chemical that causes a birth defect

• Impact depends on the time of exposure

body proportions

 during fetal period, the proportions of the body change dramatically. At 2 months the head represents about half the fetus, but by the time of birth it is one quarter of its total size

fertilization

 sperm and ovum join to form a single new cells, called a zygote

3 stages

• Zygote > conception to 2 weeks

• Embryo > 2 weeks through 8 weeks

• Fetus > 9 weeks to birth

• ZEF

two ways to study

• Cross sectional > measure different age groups at the same time

• Cannot tell if any differences are due to age

• Longitudinal

soil example understanding group differences within a group vs between a group

• Example is soil is the difference between groups is caused by poor soil (environment), not due to genes

• Even if the variation between group members is genetic, the difference between groups may be wholly environmental

epigenetics

studies how environment can influence gene expression

examples of epigenetics

• Prenatal > drugs, toxins, nutrition stress

• Postnatal > neglect, abuse, variations in care, socio-economic status

• Juvenile > social contract, environmental complexity

• Adult > cognitive challenges, exercise, nutrition

• Lifelong experiences can influence how your genes are expressed

• Gene by environment interaction

• "the level of one influences the level of another

• An example of how genes are not "destiny"

can genes explain differences between groups

no

heritability statistic

• Proportion of phenotypic (behavioral) variance that can be explained by genes

• Does not say specifically how genes influence behavior

• Can tell us that genes are important

• And to what degree

heritability range

• 0 (no genetic influence) > nurture

• 1 (entirely genetically determine) > nature

• Heritability of height is approximately .90 (meaning controlled by genes)

• 90% of all the reasons why some people are taller than others is their genes

• Personality > Heritability is approximately .50

siblings genetics/ adopted siblings

• You share both genes (approximately 50%) and environment with your siblings

• 2 biologically unrelated people > why should they be similar to each other

• Adopted siblings raise in the same home are no more similar to each other they are with someone raised in a different home

• In general, shared environment does NOT impact personality

• Adoptive families grow up together do not resemble one another in personality

• To bear repeating: the normal range of environments shared by family's children ahs little discernible impact on their personalities