-
DNA
large coiled molecule that resides in every cell in the body, except red blood cells, contains all the info needed for human development and function
-
Chromosomes
DNA is packaged with proteins to form structures called this
-
genes
small segments of DNA that contain the blueprints or planes for the production of proteins; influence specific characteristics, such as height or hair color, by directing the synthesis of proteins
-
genome
all of the genetic information contained in most of our cells
-
alleles
genes occur in pairs of ___. wei nherit one from each one of our parents
-
behavioral genetics
an area that looks at nature vs nurture in given traits
-
The Complex Connection b/w Genes and Behavior; Polygenic Influence on Behavior; Genes and the Environment; Epigenetics: How the Environment Changes Gene Expression
Four principles of behavioral genetics
-
monogenic transmission
passing on of traits determined by a single gene *Huntinton's disease
-
polygenic transmission
many genes interact to create a single characteristic (skin color, personality traits, height, weight)
-
3rd principle: Genes and the Environment
heritability: to extent to which a character
-
Twin studies
- compare pairs of fraternal and identical twins
- Results: fraternal twins share half as many genes on average as identical twins (if a trait is genetically influenced, identical twins should be more similar in that trait than fratenral twins would be. if genetics plays no role, identical twins will be no more alike than fraternal twins in that specific trait)
-
a variant sequence of DNA that is present in some people and not in others. They then assess crucial environmental experiences in people with and without the genetic marker, such as trauma and stress (use it to determine wehther individuals with the genetic marker who were raised in a particular environment are more or less likely to develop some trait such as violecne or schizophrenia)
genetic marker
-
polymorphism
individuals differ not so much in whether or not they have a gene, as in the form the gene takes
-
Epigenetics
there is a change in the way genes get expressed- that is, are activated or deactivated- without changing the sequence of DNA
-
CNS
brain and spinal cord
-
Peripheral nervous system
consists of all the other nerve cells in the body ,including the somatic nervous system and the autnomic nervous system
-
somatic nervous system
sensory information ot the brain and spinal cord and from the brain and spinal cord to skeletcal muscles (make a muscle!)
-
autonomic nervous system
serves the involuntary stesm of the body (internal organs and glands)
-
sympathetic nervous system: responsible for flight or fight response (activates bodily systems in times of emergency)parasympathetic nervous system: relaxes the body by returning it to a less active, restful state
Two branches of the ANS?
-
glial cells and neurons
CNS made up of two types of cells ___ and ___
-
Glial cells
hold the CNS toghter (glue in latin) provide structural support, promote efficient communication b/w neurons and removes cellular debris
-
Neurons
process and transmit information throughout the nervous system (within the brain ,neurons receive, integrate, and generate messages)
-
10 billion (each has 10k connections to other neurons)
more than ____ neurons in the human brain
-
1. neurons are building blocks of the nervous system (all major structures are composed of neurons)
2. information travels within a neurion in the form of an electrical signal by action potentials
3. information is transmitted by means of chemicals called neurotransmitters
Three major principles of how neurons communciate with other neurons:
-
cell body (soma)- contains a nucleus and other components needed for maintenance
axon: projection from the soma, transmit electrical impulses toward the adjacent neuron
dendrite: finger-like projects that receive incoming messages from other neurons
structure and types of neurons (3 major parts)
-
myelation
the axons of some neurons become wrapped in fatty myelin sheath (sleeve!) just like rubber around an eletrical wire, it insulates teh axon so that the impulse travels more efficiently
-
synapse
junction b/w axon and the adjacent neuron
-
-
located at the end of the axon, contains tiny sacs of neurotransmitters
-
triggers the release of neurotransmitter molecules into the gap b/w neurons (known as synaptic cleft)
-
What happens when an electircla impulse reaches the terminal button?
-
sensory neurons: receive incoming sensory information from the sense organsmotor neurons: take commands from the brain and carry them to the muscles of the body (one type of motor neuron that is active when we observe others making an action are mirror neurons (learning)interneurons: communicate only with other neurons; connect neurons in one part of the brain with neurons in another part (most common kind of neuron in the brain, outnumbering sensory and motor neurons by at least 10 to 1)
three kinds of neurons?
-
1. impulse travels one away from the dendrites along the axon and away from the soma, a process taht is both electrical and chemical (actiona potential)
2. impulse relases chemicals at the tips of neurons, which are released into the synaptic cleft to transmti the message to another neuron (neurotransmission)
neural communication: the action potential (two step process)
-
positively charged impulse that moves down an axonsince neuron is surrounded by a membrane separating the fluid inside the cell from the fluid outside the cell, it can let certain particules move through it (fluid inside and outside contain chemically charged particles called ions)
action potential (how does it happen)
-
-70 mV
when a neuron is in resting state what is the charge?
-
resting potential
What is this value called?
-
super negatively cahrged (-80 mV) temporarily
Neurons do not stay at rest however. an impulse can change the potential. While the neuron is returining to tis resting state, what does it do?
-
refractory period; cannot generate another action potential
what is this called? what can't it do at this time?
-
depolarization
causes voltage-dependent sodium channels to open and sodium ions flood into the neuron
-
+40
when the membrane potential reaches _____, sodium channels close and potassium channels open
-
all-or-none principle
point of no return: once the charge inside the neuron exceeds athreshold, the action potential fires and it always fires with the same intensity (either fires or it does not)
if depolarization threshold is not reached, theres no action potential
-
synaptic vesicles
neurotransmtiters are packed in sacs called ____
-
Enzymatic degradation: enzymes specific to that neurotransmitter bind with the neurotransmitter and destroy itreuptake: returns excess neurotransmitter to the sending, or pre-synaptic, neuron for storage in vesicles and future use
Excess neurotranmitter remains in the synaptic cleft and needs to be removed. ways?
-
graded potentials
after a neurotransmitter has bound to a receptor on the postsynaptic neuron, changes occur in that neuron's cell membrane (small changes)
they only affect the LIKELIHOOD that an action potential will occur in the receiving neuron
-
acetylcholine
controls muscle movement and plays a role in mental processes such as learning, memory, attention, sleeping, and dreaming
-
dopamine
released in response to behaviors taht feel good or are rewarding to the person or animal
-
epinephrine and norepinephrine
energizing and arousing properties (adrenaline)- produced in the brain and by the adrenal glands that rest on the kidneys
-
serotonin
dreaming and controlling emotional states (anger, anxiety, depression) - anxious ppl have low levels of this neurotransmitter
-
Gamma-aminobutyric acid
- inhibitory neurotransmitter in the brain (tell postsynaptic neurons NOT to fire)
- slows CNS activity and regulates control of neural activity
-
Glutamate
excitatory neurotransmitter (important in learning ,memory, neural processing )- facilitates growth and change in neurons (processes of early brain development)
-
the brain
collection of neurons and glial cells that controls all the major functions of teh body (thoughts, emotions, behavior)
-
hindbrain, midbrain, forebrain
three major regions of the brain
-
hindbrain
connected to the spinal cord (regulate breathing, heart rate, arousal and other basic functions of survvial)
-
medulla, pons, cerebellum
three parts of hte hindbrain?
-
medulla: regulates breathing, heart rate, and blood pressure; involved in reflexes such as coughing, swallowing, sneezing, and vomiting
pons: bridge (bridge b/w lower brain regions and higher midbrain and forebrain activity
cerebellum: little brain, contains more neurons than any other single part of the brain; responsible for body movement, balance, coordination, and fine motor skills like typing and piano playing
What does each part of the hindbrain do?
-
midbrain
smallest of the three major areas. control eye muscles, auditory and visual info, voluntary movement of the body
-
brain stem
midbrain, medulla and pons
-
reticular formation
- running through both the hindbrain and the midbrain (network of nerves)
- crucial in arousal (waking up and falling asleep)
-
forebrain
- last brain region to evolve:
- cerebrum and numerous other structures, including thalamus and limbic system
control: cognitive sensory, and motor function, regualte tmperature, reproductive functions, eating, sleeping, and display emotions
-
bilateral
two of them: one on each side of the brain (most forebrain structures)
-
thalamus
receives input from ears,eyes, skin and relays information to the part of the cerebral cortex most responsible fopr processing the specific kind of sensory information
-
includes hypothalamus, hippocampus, amygdala, and cingulate gyrus
limbic system
-
hypothalamus
- master regulator of almost all major drives and motives we have, including hunger, thrist, temeprature, and sexual behavior (controls pituitary gland, and the production of hormones)
- Feeding, flight, fight, fun
-
hippocampus
key in memory systems: sensory info frome yes, ears, skin, nose goes here; establish lasting memories
-
amygdala
small almost-shaped structure directly in front of hippocampus (connections with many other areas of the brain including structures that appear to be involved in emotion and memory
-
basal ganglia
collection of structures surrounding the thalamus involved in voluntary motor control
-
cingulate gyrus
cognitive control and attention
-
aphasia
deficiti n ability to speak or comrpehend langauge
-
broca's area
responsbile for ability to produce speech
-
wernicke's area
responsible for speech comprehension (damange resutls in fluent grammatical straesm of speech that lack meaning)
-
EEG (electroencephalography)
record electrical activity of the brain by placing electrodes on a person's scap (superior to other imaging techniques in showing WHEN brain acitivity occurs, not HWERE)
-
MRI (magnetic resonance imaging and functional MRI)
- MRI: produce detaield iamges of structure (does not tell about activity, just structures)
- FMRI: tells us whre the acitivity is occuring druing tasks by tracking blood oxygen use i nbrain tissue
-
Positron Emission Tomography (PET)
measures blood flow to brain areas in the active brain (researchers and doctors can determine which brai nareas are active during certain situations)
-
endocrine system
glands secrete chemicals called horomones (travel through bloodstreem to tissues and organs all voer the body and regualte body functions like metabolism, growht, reproduction, mood, and other processes)
-
hypothalamus
___ is not a gland
-
pituitary gland
master gland because it controls the release of hormones from glands elsewhere in the body
-
thyroid
a gland that sits in the neck region and relases hormones that control the rate of metabolism
-
pancreas
release hormones (insulin) for blood sugar levels
-
adrenal glands
hormones in response to stress and emotions
-
catecholamines
class of chemicals (neutroanitters dopamione, etc)
-
cortisol
maintaining the activation of bodily systems during prolonged stress
|
|
