Chapter 3: Biopsychology Flashcards
natural selection
Charles Darwin’s theory of evolution by natural selection
* Organisms that are better suited for their environment will survive and reproduce
* Those who are poorly suited will die off
Genetic variation and chromosomes
- the difference between individuals
Contributes to a species’ adaptation to its environment
Chromosomes: long strings of DNA
zygote: 23 chromosomes coming together
gene v allele
- Genes: sequences of DNA; controls a number of visual characteristics (traits)
- Allele: a specific version of a gene
o A gene may code for the trait of hair color, and the different alleles affect which hair color and individual has
genotype v phenotype
- Genotype: genetic makeup of an individual
- Phenotype: an individual’s inherited physical characteristics
- Polygenetic: traits controlled by more than one gene
range of reaction
- Range of reaction: asserts that our genes set our potential, and environments determine how much of that potential is reached
o Ex. if an individual is a genius and raised in a good education, they are more likely to achieve full potential than in conditions of deprivation
Genetic environmental correlation
- Genetic environmental correlation: our genes influence our environment, and the environment influences the expression of our genes
o Ex. the child of an NBA player will be exposed to basketball early, and the exposure may make them realize their genetic, athletic potential
Epigenetics
: looks beyond the genotype itself and studies how the same genotype can be expressed in different ways
o (researchers study how the same genotype can lead to different phenotypes)
o Looking at twins
dominant v recessive genes
Dominant: allele from one or both parents will result in the phenotype (ex. cleft chin)
recessive: occurs only when allele is from both parents
neuron structure
dendrite:
receives info from other neurons & transmits it to cell body
soma (cell body):
keeps cell functioning & determines if it will fire
axon:
conducts impulses away from the body
myelin sheath:
fatty insulation that surrounds axons and speeds up impulses
neuronal activity: action potential
begins when sodium ions flow into the axon
when stimulated to the point of threshold it depolarizes
impulse is sent down neuron
neuronal activity: resting potential
electrical charge of a neuron when it is not firing a neural impulse
produced by difference between intracellular and extracellular fluid
neurotransmitters
enable neurons to exite or inhibit each other
neurotransmitters: Biological perspective
focus on physiological causes of behavior
o Assert that psychological disorders like depression and schizophrenia are associated with imbalances in one or more neurotransmitter systems
agonists versus antagonists
- Agonists: chemicals that mimic a neurotransmitter at a receptor site
- Antagonist: blocks or impedes the normal activity of a neurotransmitter at the receptor
o Ex. Parkinson’s disease = low dopamine -> dopamine agonist
o Ex. Schizophrenia = overactive dopamine -> antipsychotics (antagonists)
Reuptake inhibiters
- prevent unused neurotransmitters from being transported back to the neuron
o Ex. depression = reduced serotonin
Treated with selective serotonin reuptake inhibiters
Agonist
serotonin and dopamine
serotonin:
affects neurons involved in sleep, appetite, sensory perception, temperature regulation, pain suppression, and mood
dopamine:
affects neurons involved in voluntary movement, attention, learning, memory, emotion, pleasure, and reward
acetylcholine and norepinephrine
acetylcholine:
affects neurons involved in muscle action, arousal, and memory
affects neurons involved in heart rate, slowness of intestinal activity during stress, and alertness
GABA, glutamate, and beta-endorphins
GABA:
major inhibitory neurotransmitter in the brain: brain function and sleep
glutamate:
major neurotransmitter in the brain: memory and learning
Beta-endorphin:
involved in pain, pleasure, decreased anxiety, and tension
neural activity: neurogenesis
severed axons in the spinal cord can regrow if treated chemically
stem cells can develop and mature in the brain
the nervous system (overview)
the nervous system –>
central nervous system (brain and spinal cord)
&
Peripheral nervous system –>
somatic nervous system
&
automatic nervous system –>
sympathetic nervous system
&
parasympathetic nervous system
central nervous system and peripheral nervous system
CNS
- brain and spinal cord
- processes, interprets, and stores information; issues ordered to muscles, glands, and organs
PNS
- connects CNS to rest of body
- somatic and automatic nervous system
somatic and automatic nervous systems
somatic
- responds to external senses and acts on outside world (ex. moving to not get hit by car)
- conscious or voluntary motor functions
automatic
- controls vital processes
- operates continuously and involuntarily
- sympathetic and parasympathetic
sympathetic and parasympathetic nervous system
sympathetic
- preparing the body for stress-related activities (fight or flight)
parasympathetic
- operates during relaxed states
- returning the body to normal operations
homeostasis
the state of equilibrium or balance in which biological conditions (ex. body temp.) are maintained at optimal levels
