Chapter 3 Flashcards
how many pairs of chromosomes are in the human karyotype
23
where do the two chromosomes in a pair come from
one from mom one from dad
what does the y chromosome contain
the gene that makes a male offspring
what chromosome is responsible for the sex of the child and why
the Y chromosome - because females cannot make males, therefore the sperm has the determining factor in whether or not there will be a girl or boy
what is your genotype
all of the genes you inherit, your genetic map of your body.
what are the two copies of each gene called
alleles
what is a homozygote
when you have the same two alleles one from dad and the same one from your mom
what is a zygote
the embryo in the first two weeks after conception
what is heterozygous
when you inherit two different alleles from mom and dad
what is a phenotype
the specific genes that are turned on/ expressed. These are the characteristics that come about according to how those genes are expressed
What is a dominant allele
the allele that will always win when paired with anotger allele, dominant or recessive.
what is a recessive gene
a gene that is less commonly expressed and needs another recessive gene to be expressed
what do genes do
they code for proteins
what is behaviour genetics
genetucs that deals with behaviour differences in animals and humans
what is a kinship study
a type of study done on identical and fraternal twins, separated twins, and comparing biological vs adopted siblings.
type of behavioural study
what is the fundamental unit of the nervous system
neuron
What are glial cells
support system for the neuron’s, facilitate the operation of the nervous system. They protect neurons from outside influences
what are Pyramidal cells
Cells that line up like little soldiers and incoming info fills in through the dendrites and out through the axon
what is a myelinated neuron
a neuron with insulation that allows action potentials to jump from one cell to the next
what are inter-neurons
neurons tgat send “slow” messages between diff brain areas
what is the basic anatomy of a cell
dendrites for info input, the soma for cell body, the axon which takes messages from the cell body towards other cells, tge nodes of ranvier, the terminal buttons, the synapse, dendritic spines
what are the nodes of ranvier
little pieces of bare neuron inbetween the myelin sheath, this is the only place where the neuron can generate action potential
what are the terminal buttons
the oart that are full of little vesicles that have little packets of chemicals, when the action potential reaches the cell it can split the vesicles open and target receptors on the next neuron
what is the synapse
a tiny space isolated from the other chemical environments that is very small. it is where the end of a neuron ends with the dendritic spine.
what are dendritic spines
little fuzzies that reach closer to the synapse, which makes the gap smaller
What are purkingie cells
they are little cells that line up in sheets and they smooth out the list of limb movements. Usually when your brain sends impulses for you to move, it happens in a stop motion kind of way, the purkingie cells smooth this out, like animation.
what is the blood-brain barrier
sets of astrocytes and keep things out of the brain that would be harmful (drugs)
what are schwann cells and what is the other name for them in the brain
Oligodendrocytes are insulating cells. in the body, when a neuron is cut, it might react, but the schwan cells can help regenerate it. in the brain, when a neuron is damaged, one oligodendrocyte insultes multiple fibres, and there is not enough of it to regrow the nerves
how does MS happen
when there is degenerating myelin that causes the brain to lose its ability to send fast and coordinated messages
How is electrical energy generated in the neurons
it is a separation of ions across the neural membrane. Its a potential difference like a battery
what is a semi-permeable membrane
a membrane that surrounds a neuron and allows some thing in but not others, its like a collander
What is the resting potential of a neuron
-70mV
what two elements are present in a neuron
sodium and potassium
what ions are inside vs outside a neuron
inside- potassium ions and larger anions.
outside- sodium ions and some chloride ions
what is an excitatory message
causes the cell to lose the negative charge, and the cell becomes depolarized
Inhibitory messages
cause the cell to become more negatively charged
what happens when a neuron becomes depolarized
it hits a point where it becomes activated and throws open voltage gated sodium channels that allow sodium to come inside the neuron
wgat happens to the potential difference when sodium rushes into the ion
more positive charge = more polarization
where is the only place turnover of ions can happen
the nodes of ranvier
what happens when the action potential gets to the end of the neuron and we want to pass the signal on
when the AP reaches the end of the neuron, it triggers vesicles filled with neurotransmitters to be released, they bind with specific receptor molecules and that neurotransmitter is able to produce an AP.
what does it mean when a receptor is excititatory vs inhibitory
they either stop more chemicals and neurotransmitters from being transferred or they ramp up the production and transferring of that neurotransmitter.
what is acetylcholine
A neurotransmitter tgat runs your diaphragm, is involved in the central nervous system, and is involved in learning, memory, and sleep.
what is dopamine
involved with reward NOT pleasure. it is involved in motivated behaviour
what is norepinephrine
associated with arousal, it wakes you up in the morning and makes you pay attention
what is serotonin
associated with dreaming and sleep, and emotional states
what us gamma aminobutyric acid (GABA)
number one inhibitory transmitter that inhibits other systems, involved in regulating anxiety
what is glutamate
amino acid transmitter, excitatory. involved in learning and memory,
endorphins/ endogenous opioids are small peptides that are made in neurons
endocannobinoids are fat molecules that are manufactured when a cell needs one on demand.
point form explain AP
When a neuron fires sodium gates open and sodium goes in neuron, now inside neuron more positive than outside, then, potassium channles allow potassium to rush out of the neuron, this makes the charge negative again. then the sodium pump restores it to its resting rate.
wgat is the all or nothing principle
states that the neuron fires with the same potency every time, and works like an on/off switch with no inbetween
what is the relative refractory period
when the membrane potential is slightly lower than the resting potential and it would require even more excitatory input to trigger the action input again.
what is the absolute refractory period
a time where after the AP goes through, it cannot respond again after they were just active - this ensures the AP always moves in the same direction.
what is reuptake
when the neurotransmitter is taken back into the presynaptic buttons
what is enzyme deactivation
when an enzyme destroys the neurotransmitter in the synapse
what are agonists
drugs and toxins that enhance the actions of neurotransmitters
how can an agonist enhance a neurotransmitter
introduce a substance that helps produce the neurotransmitter, block receptors on the presynaptic cell (keep in synapse longer), mimicking the action of the neuro transmitter on the post-synaptic cell (activate the receptor).
what does an antagonist do
impair the action of a neuro transmitter
how does an antagonist work
introduce a substance that makes the neurotransmitter break down, introduce substance that reduces the amount of neurotransmitter in the synapse, and blocking the postsynaptic receptiors
what is phrenology and who hypothesized this theory
phrenology was hypothesized by franz gall- if a person uses a particular mental function more than other mental functions, that part of the brain would grow
who is pierre paul la broca
one of the first scientists to spread the notion that brain regions perform specialized functions.
what is EEG
electroencephalography and it measures electrical activity in the brain, though it is hard to use because of how noisy the scan looks.
what is ERP
event related potential - a type of brain scan that involves conducting many trials with a single individual and averaging across the trials
what is a PET scan
a positron emission topography which works by injecting a relatively harmless radioactive substance into the bloodstream
what is fMRI and MRI
a strong magnetic field is used to momentarily disrupt magnetic forces around the body, which shifts the magnetic forces around the body
what is transcranial magnetic stimulation
a very fast but powerful magnetic field is used to disrupt neural activity momentarily in a specific brain region - can only be used for short durations close to the scalp
what is the largest part of tge human brain and what is it made of
the forebrain - made up of the cerebral cortex and underlying subcortical areas, two hemispheres
wgat are the four lobes of the cerebral cortex and what are they separated by
occipital, parietal, temporal, and frontal. they are separated by the central and lateral fissure
where are the occipital lobes and what do they do
they are at the back portion of the head, they are devoted almost exclusively to vision
what is the primary visual cortex and where is it located
where the brain receives and processes visual information, it is located in the occipital lobes of the cerebral cortex
what are the parietal lobes used for in the brain
for our sense of touch. the left hemisphere receives info from the right side of the body, and vice versa.
what does touch sensory information go in each parietal lobe
the somatosensory cortex
what does the somatosensory cortex do
groups nearby sensations, this is where we get the homunculus
what is the homunculus
A visualisation of how our somatosensory cortex sees our body in relation to how much we can feel those areas/move them. Wilder Penfield developed this from brain maps
what is the temporal lobes
they hold the primary auditory cortex, responsible for hearing.
what is the fusiform face area
the intersection of the temporal and occipital lobes, this area is much more active when we look at human faces.
what is the frontal lobes used for
planning and movement. holds the primary motor cortex, prefrontal cortex,
what does the primary motor cortex do, where is it
responsible for the neurons that project directly to the spinal cord to move the body’s muscles. located in the back part of the frontal lobe
what is the prefrontal cortex and where is it
responsible for directing and maintaining attention. keeping ideas in mind while distractions bombard people from the outside world. it is also used for developing and acting out plans. responsible for rational activity and social direction
wgat is the neumonic to remember the four lobes
FTOP freud takes off his Pants
what is the corpus callosum
the fatty tissue in the middle of the brain that connects the hemispheres and allow info to flow between them
what happens when the corpus callosum is severed
split brain patients, the communication is severed between the brain hemispheres.
wgat is the left vs right hemisphere good at
left is good at speaking, right is good at spatial relationships
what is the insula
part of the cerebral cortex that lies deep within the folds of lateral fissure
what are the 5 subcortical structures
thalamus, hypothalamus, hippocampus, amygdala, and basal ganglia
the insula houses the _________ cortex, what is it responsible for
gustatory. sense of taste, important for perceiving disgust
what does the thalamus do
it is the gateway to the cortex, it receives almost all incoming sensory information, organizes it, and relays it to the cortex. smell though, has a direct route to the cortex.
what is the hypothalamus used for
the brains main regulatory structure. receives influence from the body and projects its influence to everywhere in the body and brain. the hypothalamus is involved in all of the essential body functions, as well as motivated behaviours including thirst, hunger, sexual desire.
what is the hippocampus
important in the formation of new memories. creates new interconnections in the cortex with each new experience.
what is the amygdala
located in front of the hippocampus, involved in learning about biologically relevant stimuli. it emotionally processes frightening stimuli. amygdala intensifies the function of arousal during times of emotional arousal
what is the basal ganglia
crucial for planning and producing movement. it receives input from the cerebral cortex, send the input to the motor centres of the brain, and via the thalamus it sends the input back to motor planning area of the cerebral cortex.
what is the spinal cord made of
a rope of neural tissue
what does the spinal cord do
coordinating reflexes! most important function is to carry sensory information up to the brain and carry motor signals from the brain to the body parts to initiate action
when approaching the base of the skull, what does the spinal cord turn into
the brain stem: medulla oblongata, pons, midbrain
what is the reticular formation responsible for
coordinating brain functions necessary for survival. it is just really a network of neurons
what is the cerebellum
large protuberance connected to the back of the brain stem. important for proper motor function. Important in motor learning and motor memory. it operates unconsciously
what are the two components of the Peripheral nervous syste
somatic nervous system and autonomic nervous system
what does the SNS do
transmit sensory signals to the CNS via nerves. basically performs voluntary motor movements
what does the CNS do
send signals through the SNS to muscles, joints, and skin to initiate, modulate or inhibit movement.
what does the ANS do
regulate the body’s internal environment by stimulating glands and maintaining internal organs.
what is the endocrine system
a communication network that influences thoughts, behaviours, and actions.
what is the main unit of the endocrine system
horomones
what are horomones
chemicals released into the bloodstream by the endocrine glands
what are the endocrine glands
pancreas, thyroid, adrenal gland, testes/ovaries, PITUITARY
what is the endocrine system controlled by
hypothalamus which sends signals to the pituitary gland
what does a releasing factor do and where does it come from
causes the pituitary to release a hormone specific to that factor. comes from hypothalamus
how is the pituitary like the control centre of the endocrine system
it controls all other glands, and governs major processes such as development, ovulation, and lactation. it also influences stress reactions and sexual behaviours
what is the growth horomone GH and what does it do
hormone released from the pituitary that promotes bone, cartilage, and muscle tissue to grow/ regenerates them after injury. the releasing factor for GH stimulates the eating of protein, which is involved in the sleep/wake cycles.
what is brain plasticity
the ability for the brain to change in response to experience or injury
what is the production of new neurons called
neurogenesis
what is cortical reorganization
after injury where the brain can reorganize itself and different parts of the brain can “cover” damaged functions
what is the peripheral nervous system (PNS) comprised of
anything outside the brain and spinal cord
what is the autonomic nervous system comprised of
sympathetic and parasympathetic nervous system
