biopsychology year 12 content Flashcards
CNS description
*contains brain and spinal cord
*division from human nervous system
peripheral nervous system description
nerve cells that carry information to or from CNS
spinal cord description
*receives and transmits information to and from the brain to the peripheral nervous system
*responsible for reflex actions
what is the first divide of the peripheral nervous system?
*somatic
*autonomic
somatic nervous system description
*receives information from sensory receptors
*controls muscle movement
autonomic nervous system description
*works automatically
*tells our heart to beat and our digestive system to release certain enzymes
*has two sub divisions: sympathetic and parasympathetic nervous system
differences between somatic and autonomic
*SNS has sensory and motor pathways, ANS is purely motor
*ANS controls internal organs and glands of the body when SNS controls skeletal and muscle movement
*ANS control centres are in the brain stem, SNS carries commands from motor complex
parasympathetic nervous system description
*relaxes individual once emergency has passed
*slows heart rate and blood pressure
sympathetic nervous system description
*prepares body for emergency (fight or flight)
*increases heart rate and blood pressure and dilating blood vessels in the muscles
*supplies more blood to brain, heart and muscles by reducing blood flow from skin and digestive system
dendrite description
at the end of a neuron, receives signals from other neurons or sensory receptors
myelin sheath description
fatty layer covering the axons to speed up electrical impulses
terminal buttons description
communicate with the next neuron in the chain across the synapse, found at the end of the neuron
sensory neuron description
*carry messages from sensory receptors to CNS
*found in ears, eyes, tongue and skin
*convert info from sensory receptors into neural impulses that are passed onto the brain or spinal cord
*long dendrites and short axons
relay neurons description
*connect sensory neurons to motor neurons
*short dendrites and axons
motor neurons description
*connect CNS to muscle glands
*located in CNS and project their axons outside to control the muscle movement
*releases neurotransmitters that bind to receptors to trigger the muscle movement
*short dendrites and long axons
excitation definition
*leaves post synaptic neuron positively charged
*more likely to fire
*e.g. adrenaline
inhibition definition
*leaves post synaptic neuron negatively charged
*less likely to fire
*e.g. GABA
explain reuptake
*occurs when the neurotransmitter returns to the presynaptic neuron
*the quicker it’s taken up, the shorter the effects last
*enzymes can ‘turn off’ neurotransmitters by binding to them after they have stimulated the post synaptic neuron
why can neurotransmitters only travel in one direction at the synapse?
*synaptic vesicle contains neurotransmitter which is only released from the presynaptic membrane
*receptors are only present in the postsynaptic membrane
*the binding of the neurotransmitter and receptor is what allows the electrical impulse to carry on
*diffusion from neurotransmitters mean they can only go from high to low concentration, so pre to post synaptic neuron
what hormone does thyroxine release an what does it do?
*releases thyroxine
*regulates metabolic rate and growth rate
what hormone does pineal release an what does it do?
*releases melatonin
*regulates arousal, sleep-wake schedule and biological rhythms
what hormone does the pancreas release an what does it do?
*insulin and glucose
*regulates blood sugar levels
what hormone does the ovaries release an what does it do?
*oestrogen
*effects the reproductive gland
what hormone does the testicles release an what does it do?
*testosterone
*effects reproductive gland
describe the fight or flight response
*stressful event, hypothalamus sends a message to the pituitary gland, releases adrenocorticotrophic hormone (ACTH)
*ACTH causes the adrenal glands to release adrenaline, which causes fight or flight
*parasympathetic branch puts the body back to normal afterwards
what does Gray suggest about fight or flight?
*humans avoid confrontation, and freeze as a response
*when frozen, humans are hyper-vigilant, thinking about how they can avoid the threat best
what does Taylor et al suggest about fight or flight?
*women are more likely to protect offspring and form alliances with other women (‘tend and befriend’). running is seen as a sign of weakness because offspring will be in danger
*fight or flight is a males response to danger
