Chapter 3 Biology Flashcards
(130 cards)
1
Q
Neurons are…
A
individual cells in the nervous system that receive, integrate, and transmit information
***They are basic links that permit communication within the nervous system
most communicate with other neurons, some communicate with sensory organs and to muscles that move the body
2
Q
name 3 types of neurons
A
sensory neurons
interneurons
motor neurons
3
Q
Name the 7 component parts of the neuron and describe their functions
A
Soma is the cell body containing the nucleus
Dendrites are the parts of the neuron that are specialized to receive information
Axon is a long thin fibre that transmits signals away from the soma to other neurons or to muscle or glands
Myelin Sheath is insulating material, derived from glial cells, that encases some axons white fatty substance that speeds the transmission of signalsthe degeneration of this sheath leads to muscle control loss as seen in MS
Terminal Buttons are clusters at the of the axon that secrete chemicals called neurotransmittersserve as messengers activating neighboring neurons
A synapse is a junction where information is transmitted from one neuron to another - it is the point at which neurons interconnect
Neurotransmitters chemicals serve as messengers activating neighboring neurons
4
Q
Soma is
A
the cell body containing the nucleus
5
Q
Dendrites are
A
the parts of the neuron that are specialized to receive information
6
Q
Axon is
A
is a long thin fibre that transmits signals away from the soma to other neurons or to muscle or glands
7
Q
Myelin Sheath
A
is insulating material, derived from glial cells, that encases some axons
white fatty substance that speeds the transmission of signalsthe degeneration of this sheath leads to muscle control loss as seen in MS
8
Q
Terminal Buttons are
A
clusters at the end of the axon that secrete chemicals called neurotransmitters
9
Q
A synapse / synaptic cleft is
A
a junction where information is transmitted from one neuron to another - it is the point at which neurons interconnect
10
Q
Neurotransmitters are
A
chemicals that serve as messengers activating neighboring neurons
11
Q
GLIA are
A
(literally glue) cells found throughout the nervous system that provide various types of support for neurons
***much smaller than neurons
outnumber them 10 to 1
account for 50% of brains volume
supply nourishment/help remove waste
provide insulation around axons
the myelin sheathe are derived from special types of glia cells
orchestrate the development of the nervous system in the human embryo
recent studies indicate that they may also send and receive chemical signals
deterioration may be linked to Alzheimer’s and Parkinson’s
they are linked to memory formation
12
Q
action potential is
A
also known as neural impulse
the change in electrical potential that occurs between the inside and outside of a nerve or muscle fiber when it is stimulated, serving to transmit nerve signals
***both inside and outside of the neuron are fluids containing electrically charged atoms and molecules called ions
positively charged sodium and potassium ions and negatively charged chloride ions flow back and forth across the semi-permeable membrane of the axon (but not at the same rate)
the going back and forth from negative to positive depolarizes the charge along the neuron and sends an impulse through it with signals
13
Q
resting potential is
A
a neuron’s stable, negative charge when the cell is inactive;
-70 millivoltsi.e. the neuron at rest is a store of potential energy like a tiny battery
14
Q
absolute refractory period is
A
the minimum length of time after an action potential during which another action potential cannot begin
***it’s basically downtime of 1 or 2 milliseconds of rest b4 firing up again
15
Q
Describe the all-or-none law of the neural impulse
A
the all or none law shows that neurons either fire or they don’t (action potential or not)
i.e. weaker stimuli do not make weaker action potentials
but the amount of times per second that it fires will be determined by the stimuli and thus affecting the end muscle or whatever
so a dim light may cause the neuron to fire 5 times per second while a bright light might make it fire 100 times per second
different neurons transmit impulses at different rates. ones with thicker axons faster, thinner slower
16
Q
is a neuron at rest active?
A
a neuron at rest has a slow constant rate of firing that is interpreted by the nervous system as no response
17
Q
the arrival of an action potential at an axon’s terminal buttons triggers what?
A
the release of neurotransmitters (chemicals that transmit information from one neuron to another)
18
Q
synaptic vesicles are
A
where neurotransmitters are stored
***the neurotransmitters are released when the vesicles fusewith the membrane of the presynaptic cell and its contents spill into the synaptic cleft
19
Q
synaptic cleft is
A
a microscopic gap between the terminal button of one neuron and the cell membrane of another neuron
20
Q
what are the sending and receiving neurons referred to as?
A
the neuron that sends the signal is called the presynaptic neuron and the one that receives it is called the post synaptic neuron
21
Q
postsynaptic potential (PSP) is
A
avoltage change at a receptor site on a postsynaptic membrane
***do not follow the all or none law – they are graded potentialsthey increase or decrease the probability of a neural impulse in the receiving cell
22
Q
Temporal summation is
A
when the one neuron is firing many NTs in a row and thereby raising the PSP to the threshold needed
23
Q
Spatial summation is
A
when a neuron gets fired onby several other neurons simultaneously, so it increases the likelihood that it’ll turn a PSP into an action potential
24
Q
excitatory postsynaptic potential
A
increases the likelihood that the postsynaptic neuron will fire action potential
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negative postsynaptic potential
decreases the likelihood that the postsynaptic neuron will fire action potential
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reuptake
is a process in which neurotransmitters are sponged up from the synaptic cleft by the presynaptic membrane
***this might happen because a neurotransmitter becomes inactive based on enzymes or drifts away
this process conserves NTs and puts them back to use for later use
27
integration happens as
signals arrive at many synapses before it decides to fire a neural impulse or not - if PSP is high then fire if inhibitory PSP then no
***millions of neurons must fire in unison to produce the most trifling thought interlinked in complex pathways, chains, circuits and networks; patterns of neural activity
interconnected neurons that frequently fire together or sequentially to perform certain functions
28
Synaptic pruning
the nervous system generally produces more synapses than needed and gradually eliminates the less-active synapses eg: the number of synapses in the visual cortex peaks at around age 1 then gradually declines
it is a key process in the formation of neural networks
29
cell assemblies was the work of which psychologist? and what was his book?
the linkage of neurons to form networks was the work of Donals Hebb
one neuron stimulating another neuron repeatedly produces changes in the synapse; learning has taken place; known as the Hebb Synapse"the organization of behaviour" (1949)
30
can NTs fit in any receptor site?
No. just as a key has to fit a lock to work, transmitters has to fit into a receptor site for binding to occur such specialization reduces cross talk between densely packed neurons, making the nervous system’s communication more precise
31
the properties and functions of acetylcholine (ACh)
is the only transmitter between motor neurons and voluntary muscles every move you make depends on this transmitter being released to your muscles by motor neurons
also active in attention, arousal and memory
32
Name 3 monoamines and their functions
dopamine used by neurons that control voluntary movement
degeneration of these neurons = Parkinson's
overactivity = schizophrenia (activated by cocaine and ampethamines)
norepinephrine lower levels is linked to depression
serotonin used by neurons for sleep, wakefulness and eating habits
cocaine and other amphetamines create temporary alterations in monoamines, accounting for the strong effects
33
agonist is
a chemical that mimics the action of a neurotransmitterfor eg. nicotine is an agonist for (ACh)if you smoke tobacco, some of your ACh synapses will be stimulated by the nicotine that arrives in your brain.
At these synapses the binds to receptor sites, causing postsynaptic potentials (PSPs)
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antagonist
chemical that opposes the action of a neurotransmitter for eg: the key works, but instead of causing a PSP, it blocks the it.
indigenous use curare chemical on arrow tips. if they wound an animal the curare blocks synapses from nerve to muscle, paralyzing the animal
35
function of GABA and Glycine
they are amino acids
produce only inhibitory postsynaptic potentials regulation of anxiety
this is versus monoamines that can have excitatory or inhibitory PSPs
*gaba is a mellow nice lady that is like Gabby...just chill*
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serotonin
used by neurons for sleep, wakefulness and eating habits
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norepinephrine
lower levels is linked to depression - modulation of mood and arousal
*no refrain = depression
refrain = the degree of happiness in a song*
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Glutamate functions
Amino acid
excitatory effects only
learning and memory
*get excited when I see my mate because I remember all the good times we have and learned and we are bonded so glued together together*
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dopamine
used by neurons that control voluntary movement degeneration of these neurons = Parkinson's
overactivity = schizophrenia (activated by cocaine and ampethamines)
40
morphine is
a painkilling drug derived from the opium plant
exerts its effect by binding to specialized receptors in the brain
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endorphins
internally produced chemicals that resemble opiates in structure and effect
*sound like morphine*
they contribute to the modulation of pain
produce feelings of pleasure“runner’s high” endorphins are released
42
Central Nervous System consists of
the brain and spinal cord and nerves inside of bones
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peripheral nervous system is and is divided into
is made up of al the nerves that lie outside the CNS and it is divided into the
somatic nervous system and autonomic nervous system
which splits into the sympathetic and parasympathetic
44
Nerves are
bundles of neuron fibres (axons) that are routed together in the peripheral nervous system
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The somatic nervous system is
made up of nerves that connect to voluntary skeletal muscles and to sensory receptors
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The autonomic nervous system
connects to the heart, blood vessels, smooth muscles and glands ultimately governed by the CNS, it governs automatic, involuntary and visceral functions such as heart rate, digestion and perspiration it mediates emotions; stage freight symptoms, panic symptoms, lust
47
affervent nerve fibers are
axons that carry info towards the CNS from the periphery of the body (senses)
48
effervent nerve fibres
are axons that carry info outward from the CNS to the periphery of the body (e is after a)
first you get info from senses so (a)ffervent, then brain responds with (e)ffervent
each nerve in the body contains axons of each type; somatic nerves are two way streets; in and out; somatic let’s you move around and feel the world
49
describe fight or flight and which NS is responsible
as a result of fear, blood pressure surge, breath speeding up, desire to defecate, controlled by the autonomic NS
50
The sympathetic division
is the branch of the ANS that mobilizes the body’s resources for emergenciesit creates the fight or flight effect
51
Parasympathetic division
is the branch of the ANS that generally conserves bodily resources slows heart rate, reduces blood pressure, promote digestion
restores the body after fight or flight
52
meninges serve what function
sheaths that protect the spine and brain in the CNS
53
cerebrospinal fluid has what function?
nourishes the brain and provides a protective cushion for it
it is found in the hollow cavities in the brain called ventricles
54
Spinal cord connects what?
the brain to the rest of the body via the peripheral NS
it is also bathed in cerebrospinal fluid and enclosed by meninges
it is an extension of the brain
runs from the base of the brain to just below the waste basically a messenger from peripheral to the brain and back
55
the brain consists of
billions of interacting cells that integrate information from inside and outside the body coordinating the body’s actions and enables human beings to talk, think, remember, plan create and dream
56
What is an electroencephalograph (EEG)
a device that monitors the electrical activity of the brain over time by means of recording electrodes attached to the surface of the scalp
measures brain waves in frequency (cycles per second) and amplitude (voltage)
during different states of consciousness/behaviours/activity (meditation as an example)/neural basis for sleep can measure brain damage
57
describe Beta Waves
13-24 Cycle Pr Second associated with normal waking thought and alert problem solving
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Alpha Waves
8-12 Cycle Pr Second associated with deep relaxation and meditation (Alpha - the best!)
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Theta Waves
4-7 Cycle Pr Second associated with light sleep and dreaming
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Delta Waves
high amplitude but under 4 Cycle Pr Second associated with deep, dreamless sleep
61
what is lesioning
involves destroying a piece of the brain (by inserting an electrode and and passing a high frequency current through it to burn tissue and disable the structure)
stereotaxic instrument used animal testing
62
what is electrical stimulation
involves sending a weak electrical signal into the a brain structure to stimulate/activate it
mainly done on animals but sometimes on humans when they are having brain surgery.
63
describe what Wilder Penfield did
operated on 1000 patients while they were conscious and asked them questions to gather info about how and when certain areas of the brain lit up he discovered ways to treat epilepsy through surgery
64
describe Transcranial magnetic stimulation
new technique that allows scientists to temporarily enhance activity in a specific area of the brain
basically a coil that is charged and held over different parts of the brain to activate/deactivate areas and test to see if certain areas correspond to tasks like cognitive ability etc..
limited in that it can’t penetrate deep in the brains, just surface
65
what is computerized tomography (CT)
computer enhanced x-ray of brain structure generates a horizontal slice based on many images
least expensive and used a lot in research
schizophrenia was associated with enlarged ventricles through this method
66
describe PET (positron emission tomography)
radioactively tagged chemicals are introduced into the brain which can be monitored with x-rays which provide a color coded map indicating which areas of the brain become active when doing various activities
because it’s in real time with chemical color coding, advantage is that they can study the activity neurotransmitters; i.e. how cocaine affects dopamine
67
describe MRI (Magnetic resonance imaging)
uses magnetic fields, radio waves and computerized enhancement to map out the brain structure
a lot more accurate than CT - provides a 3D in high res
critical in determining that depression is linked with shrinkage in hippocampus
68
describe FMRI (Functional magnetic resonance imagine)
is a variation on MRI that monitors blood flow and oxygen consumption in the brain to identify areas of high activity
maps actual activity in the brain over time like a PET but with greatly enhanced precision
mapped areas associated with cocaine craving/the contemplation of a loved one/visual recognition of shapes and textures/high risk decision making
69
hindbrain consists of what 3 parts
includes cerebellum, medulla and pons
70
medulla functions
(attached to the spinal cord) is responsible for largely unconscious but vital functions
blood circulation
breathing, muscle tone, reflexes like sneezing and coughing
*mysterious name - unconscious functions like breathing and circulation* reptile brain she connects the spinal cord, so is right at the base
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function of Pons
sleep and arousal
*sounds like the fons = arousal and then once you've been arouse you have to sleep*
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function of Cerebellum
(little brain) coordination of movement, equilibrium/physical balance fine motor skills writing and typing
is one of the first areas depressed by alcohol ****she's a figure skater*
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decribe the midbrain
the link between hind brain and forebrain so it has a few of the other characteristics
vision and hearing integration locating where things are in space
dopamine gets released from midbrain
parkinson's has roots there voluntary movements arousal and sleep
muscle reflexes breathing pain perception
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reticular formation is
group of fibres in mid-brain associated with arousal and sleep / wakefulness / alertness arousal and sleep
muscle reflexes breathing pain perception it touches the medulla and pons so functions are similar
75
forebrain is
the largest part of the brain including the thalamus, hypothalamus, limbic system and cerebrum
the wrinkled surface of the cerebrum is the cerebral cortex
76
Thalamus is
right in the center of the cross section -- it’s a relay through which all sensory information except smell must pass to get to the cerebral cortex
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Hypothalamus
FIGHT FLIGHT *sounds like a gladiator - thalamus the hypo!! *controls autonomic nervous system - heart, blood vessels, smooth muscles and glands vital link between brain and endocrine system because it's right next to the pituitary gland
vital role in four F’s: fighting fleeing feeding and mating
plays a role in hunger/thirst/temperature regulation
is a structure found near the base of the forebrain that is involved in the basic regulation of basic biological needs (Hypo means under, so under the Thalamus)
78
Limbic System
loosely connected network of structures located along the border between the cerebral cortex and deeper subcortical areas
includes parts of the thalamus and hypothalamus hippocampus and amygdala
regulation of emotions, memory and motivation recently linked to optimism
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amygdala function
emotion and aggression
part of limbic system
*emotions are buried deep -- little ball but hidden*
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Hippocampus
limbic system
learning and memory so close to the amygdala so learning and memory are closely tied to emotions
*l'ami de gdala*
81
Olds’s research in brain was what
self-stimulation
discovered that the pleasure centre was in the limbic system
animals who would press a lever a thousand times per hour to get a stimulation in a part of the brain that was implanted with an electrode
82
cerebrum is
the most complex mental activities including learning, remembering, thinking, voluntary movement, and consciousness itself
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function of the pituitary?
"master gland" that regulates othe rendocrine glands
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the cerebral cortex
is the convoluted outer layer of the cerebrum folded and bent so it can fit in the skull
packed with neurons sometimes called grey matter
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cerebral hemispheres are
the right and left halves of the cerebrum
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what are the four lobes of the cerebrum called and where are they and which cortex are associated with them
occipital lobe at the back where visual signals are sent and processing begins primary visual cortex
parietal lobe in front of it and relates to the sense of touch, visual input and position in space primary somatosensory cortex (sense of touch)
temporal lobe is below parietal lobe / auditory processing primary auditory cortex (temporal is near the ears - think temples - ears and temples)
frontal lobe the biggest relates to movement of muscles primary motor cortex
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corpus callosum
is the structure that connects the two cerebral hemispheres
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brain plasticity refers to
the brain’s ability to change structure and function
Example - somatosensory cortex is enlarged with string players who use a certain hand for fingering
In blind people, cortex that is usually used for visual processing is enlisted to help with verbal skills some structures can take over for other structures, if necessary.
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Neurogenesis is
the formation of new neurons
It was thought that no new neurons would be generated after infancy but research is showing that the adult brain can generate new neurons in the olfactory bulb of the hippocampus
Thought to contribute to the process of natural repair after brain damage
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Stem cells are
unspecialized cells that renew themselves through cell division and that can under certain circumstances be induced to become cells suitable for other specialized purposes such as the beating cells of the heart and neurons
Can come from other parts of the body or other patients
Can also come from eggs that are fertilized in vitro, which bring sup a ton of ethical questions
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Broca's brain
left side of the frontal lobe responsible for speech production (he's the talkative one)
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Wernicke's area
is in the temporal lobe and responsible for language comprehension (she listens)
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In split-brain surgery
the bundles of fibers that connects the cerebral hemisphere (the corpus callosum) is cut to reduce the severity of epileptic seizures
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Perceptual asymmetries
are left-right imbalances between the cerebral hemispheres in the speed of visual and/or auditory processing
Example is when verbal stimuli is sent to the left side via the right eye, people can process it faster that when it is sent to the left eye and right side, because the right side has to make a trip to the left side of the brain to confirm what it is on a verbal level
The opposite holds true for visual-spatial tasks
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in general differientiate the skills of either side of the brain
Left: Verbal processing, language, speech, reading, writing and the right is good for
Right: Non-verbal processing such as spatial, musical, visual recognition, and perceiving others' emotions
96
The endocrine system consists of what?
glands that release hormones into the bloodstream; hormones help control bodily functioning
***They are like neurotransmitters in the nervous system
Stored for subsequent release as chemical messengers
Diffuse into the bloodstream and bind to receptors on target cells
Some even do double duty like norepinephrine
Whereas neurons travel short distances at lightning speed and along very specific pathways, hormones travel to distant cells much slower and are much less specific
97
Which part of the brain is responsible for controlling much of the endocrine system ?
Hypothalamus
98
function of the Pituitary gland
releases a wide variety of hormones that fan out around the body stimulating actions in the other endocrine glands
It's considered the master gland of the endocrine system though the hypothalamus is the real power behind the throne
Oxytocin is a hormone released by the pituitary gland, which regulates reproductive behaviour
Triggers contractions when a woman gives birth
Stimulate lactation
Links to feelings of bonding/trust and empathy arising in research
99
Can the Hypothalamus send signals to both the endocrine system and the autonomic NS?
At times the hypothalamus will send signals to the endocrine system and the autonomous nervous system for the fight/flight response, so it's acting on both fronts
100
Describe some of the ways in which the endocrine system works
Hormones released in stomach aid in digestion
Kidney, hormones play a part in regulating blood pressure
Pancreatic hormone of insulin regulates sugar
They are pulsatile in that are released several time a day in brief bursts or pulses that only last a few minutes
The levels increase and decrease in rhythmic patterns through the day
101
Behavioral genetics is
an interdisciplinary field that studies the influence of genetic factors on behavioural traits
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Chromosomes are
strands of DNA molecules that carry genetic information
Found in the nucleus of each cell
Every cell except for sperm and egg contain 46 chromosomes: 23 pairs with one strand from each parent
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A zygote is
a single cell formed by the union of the sperm and the egg
Has 23 pairs, 46 chromosomes that appear in subsequent cells that come from the one zygote
Each chromosome contains thousands of biochemical messengers called genes
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Genes are
DNA segments that serve as the key functional units in hereditary transmission
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In a Homozygous condition the two genes in a specific pair are
the same
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in a Heterozygous the two genes in a specific pair are
different
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Dominant gene is
the one that is expressed when pair genes are different
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Recessive gene is the one
that is masked when pair genes are different
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Genotype refers to
a person's genetic makeup
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Phenotype refers to
the ways in which a person's genotype is manifested in observable characteristics. I have green eyes and brown hair. These are phenotypes
May change over time and modified by environmental factors
Genotypes translate into phenotypes in a variety of ways
Not all work according to dominance
In some instance the blend and average out
111
Polygenetic traits or characteristics are
a trait that is controlled by two or more genes, therefore the trait may result in a hybrid of the two parents - i.e. one parent is 6 feet and one is 5 feet, the kid is 5' 5"
**Skin color, motor coordination
Most psychological conditions appear to be polygenetic
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Family studies
researchers assess hereditary influence by examining blood relatives to see how much they resemble one another on a specific trait
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in twin studies what are researchers assesing ?
researchers assess hereditary influence by comparing the resemblance of identical twins and fraternal twins with respect to a trait
114
differentiate the biological process between identical and fraternal twins
in identical, the sygote splits into 2 = 100% genetic similarityin fraternal two sperms fertilize 2 eggs = 50% genetic similarity
115
define genetic mapping
is the process of determining the location and chemical sequence of specific genes on specific chromosomes
***it will allow scientists to investigate how heredity influences specific aspects of behaviour
116
define epigenetics
the study of heritable changes in gene expression that do not involve modification to the DNA sequence
***epigenetic tags tell a gene to act a certain way. these tags are a result of environmental factors
rats were tested where the smell of fruit and electro shock were combined. they developed a hate for the smell of fruit. this trait was passed on to future generations even though the offspring had not smelled fruit.
the dna of future rats was not altered but the epigenetic tags learned that smell of fruit is bad, so they turned certain traits on/off that they would not have prior to the experiment.
schizophrenia, heart disease are other possible examples
117
define evolutionary psychology
analyzes behavioural process in terms of their adaptive significance
118
with regard to Darwin, define fitness
refers to the reproductive success (number of descendants) of an individual organism relative to the average reproductive success in the population
119
what concept did Darwin borrow from Thomas Malthus to come to his theory of evolution
population increases, resources dwindle, so there's more competition
120
define Natural Selection
posits that heritable characteristics that provide a survival or reproductive advantage are more likely than alternative characteristics to be passed on to subsequent generations and thus come to be "selected" over time
***this process works on populations, not organisms -- evolution occurs when the gene pool in a population changes gradually as a result of selection pressures
121
why were Darwin's concepts controversial?
* life is the result of unplanned natural process rather than divine creation
* humans are not unique and share common ancestry with other species
122
Name 5 refinements to Darwin's evolution theory
Genetic drift
Mutation
Gene flow
adaptation
inclusive fitness
123
define genetic drift
random fluctuations in gene frequencies over generations as a result of chance alone
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define Mutation
is a spontaneous heritable change in a piece of DNA that occurs in an individual organism
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define gene flow
occurs when some individuals leave a population (emigrate) and others immigrate
126
define adaptation
is an inherited characteristic that increased in a population (through natural selection) because it helped solve problem of survival or reproduction during the time it emerged
***some things linger from back when they were necessary such as eating fatty food when that food source was a good source of calories but very scarce but now its a cause for fucking up the body so it's turned on itself, or fight or flight which was useful but now mainly causes over anxiety
many aspects of human nature reflect the adaptive demands faced by our ancient ancestors rather than contemporary demands - they will gradually get eliminated but the process is very slow.
127
define inclusive fitness
(Hamilton) is the sum of an individual's reproductive success plus the effects the organism has on the reproductive success of related others
i.e. he's had a lot of kids, but now there's a fire in the house, so he'll risk his life so the genes can continue if he saves the kids.
128
Can behaviours be considered as adaptive traits?
yes.
stotting in gazelles
grasshopper burying itself in stones that camouflage it
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pre frontal cortex
working memory and reasoning about relations
130
cerebral laterelization
the degree to which right and left hemispheres handle various cognitive and behavioural functions
