chapter 3 Flashcards
genetics; brain/body development
genome
the complete set of DNA of any organism, including all of its genes
genotype
the genetic material an individual inherits
phenotype
the observable expression of the genotype (body/behavioral characteristics)
environment
every aspect of individuals and their surroundings other than genes
- parents’ genotypes – child’s genotype
involves the trans motion of genetic material from parent to offspring
chromosomes
molecules of DNA that transmit genetic information
46 chromosomes –> 23 pairs –> each pair carries genes of same type
- genetic diversity and individual differences
DNA
molecules that carry all of the biochemical instructions involved in tithe formation / functioning of an organism
genes
sections of chromosomes that are the basic unit of heredity in all living things
random assignment
egg and sperm formation is always random
crossing over
the process which sections of DNA switch from one chromosome to the other
- variability
mutation
a change in a section of DNA
- ex causes: radiation, infection, chemical exposure
4 types: substitution, deletion, insertion, inversions
sex chromosomes
chromosomes (X and Y) that determine sex at birth
female: XX
male: XY
- child’s genotype – child’s phenotype
relation between one’s genotype and one’s phenotype
endophenotypes
intermediate phenotypes, including the brain and nervous system, that do not involve overt behavior
regulator genes
genes that control the activity of other genes
- switch on/off genes
alleles
2 or more different forms of a gene
dominant allele
if present, gets expressed
recessive allele
not expressed if dominant allele is present
homozygous
having 2 of the same allele for a trait
polygenic inheritance
inheritance pattern in which traits are governed by more than one gene
- child’s environment – child’s phenotype
impact of the environment on the child’s phenotype
phenylketonuria (PKU)
a disorder related to defensive recessive gene on chromosome 12 of the amino acid phenylalanine
gene environment interaction
situation in which the effects of genes depend on the environment in which they are expressed
parent contribution to child’s environment
parents’ genes affect their phenotypes (and thereby influence the family environment) and child outcomes
genetic nurture
children’s outcomes can be predicted by parental alleles that the child did not inherit
- child’s phenotype – child’s environment
restates active child theme as a source of their own development
- children create their own environment by actively selecting surroundings and experiences that match their interests/personalities
- child’s environment – child’s genotype
the structure of the genetic code remains “fixed” during one’s lifetime, the expression of the genetic code is altered
epigenetics
the study of stable changes in gene environment that are mediated by environment
DNA methylation
regulates the amount of protein predicted by a given one
family studies
examine extent to which a trait runs in families raised in same home
twin studies
compares MZ and DZ twins
adoption studies
examines extent to which adopted children resemble their adoptive vs biological families
heritability
extent to which genes contribute to differences in a trait across individuals
- expressed as a percent
- reflects environment in some way
- not fixed; can be changed
important aspects about heritability
Heritability applies only to populations
Heritability estimate applies only to a particular population living in a particular environment
Heritability estimates reflect the environments of the populations of individuals they are derived
Heritability estimates can change as a function of developmental factors
High heritability does not imply immutability
There is a high sampling bias in genetic studies (lack of diversity)
molecular genetics research designs
examines specific DNA sequences to identity mechanisms that link genes and behaviors
genome-wide association studies (GWAS)
link specific DNA segments with particular traits
genomes-wide complex trait analysis (GCTA)
takes estimates of genetic resemblance across large groups of individuals
environmental effects
children in the same family do not necessarily share the same environment
- effects of the environment are likely due to many experiences of small effects working together
- harder to measure
neuron (function and parts)
used to communicate
- cell body (soma)
- dendrites
- axons
- axon terminals
- synapse
- astrocyte (glial cells)
cell body (soma)
manufactures new cell components
dendrites
receives input from other neurons
axons
sends messages to other neurons
axon terminals
synaptic vesicles (contains neurotransmitters for messaging)
synapse
when neurons communicate with one another
- terminal: neurotransmitters travel space
astrocyte
glial cells
- protects neurons
- blood-brain barrier
- respond to injury
- form myelin sheath
cerebral cortex
80% of the brain
- analyzes sensory information
- 4 regions: occipital lobe, temporal lobe, parietal lobe, frontal lobe
occipital lobe
vision
temporal lobe
speech and language
auditory information
memory
hippocampus
parietal lobe
sensory processiing
perception
primary sensory cortex
primary sensory cortex
initially processes sensory information and passes it to the association cortex
frontal lobe
executive function
- motor
- working memory
- ability to plan
- prefrontal cortex
cerebral lateralization
hemisphere are specialized for different models of processing
neurogenesis
creation of new neurons ini the adult brain
myelination
speeding up connections
synpatogensis
formation of new connections
pruning
elimination of synapse / neurons
plasticity
the brain’s ability to change in response to experiences
experience-expectant plasticity
describes the role of general human experience in shaping brain development
experience-dependent plasticity
occurs when neural connections are created and reorganized throughout life as a result of experience
magnetic resonance imaging (MRI)
image created by measuring the release of energy from water in tissue after being exposed to a magnetic field
pros and cons of MRI
pros
- high spatial resolution
cons
- low temporal resolution
- indirect measure of brain activity
structural MRI to functiontional MRI is what to what?
brain anatomy to brain function
electroencephalograph (EEG)
HANS BERGER
- developed this to measure electoral activity generated by the brain
pros and cons of EEG
pros
- measures brain activity
- high temporal resolution
cons
- low spatial resolution
near-infrared spectroscopy
neuroimaging technique
pros and cons of near-infrared spectroscopy
pros
- allows for movement
- high sampling rate
cons
- only look at cortical activity
secular trends
changes in physical development that have occurred over generations
infant feeding
some studies demonstrating links between breast feeding and higher IQ (not always)
development of food preferences
- preference for salt emerges around 4 months
- children are exposed to associative learning
obesity
- 15% of teens in US in 2017 were obese
- global issue
- genetic and environmental
vaccines
- important in healthy physical development
- operate on herd immunity
