biopsych Flashcards
what is the CNS?
the CNS is the central nervous system consisting of the brain and spinal chord
what is the role of the brain?
to take information in from sensory receptors (i.e. rod cells in eyes) and to send out instructions to muscles to combat instructions (move hand to put up sunglasses)
what is the role of the spinal chord?
runs along the back and consists of a network of nerves allowing for communication between the brain and the muscles
what is PNS?
PNS stands for peripheral nervous system and consists of all other nerves which aren’t CNS (brain or spine).
role of PNS?
to relay information via nerve impulses from the rest of the body back to the CNS.
what are the two subsystems of PNS?
somatic nervous system and the autonomic nervous system
what is the somatic nervous system?
includes voluntary, conscious movements, along with 12 pairs of cranial nerves and 31 pair of spinal nerves. e.g. feeling a rough/smooth surface.
what is the autonomic nervous system?
involuntary actions like heart beat. Important role in homeostasis.
what are the two subsystems of ANS?
sympathetic nervous system and parasympathetic nervous systems
what is sympathetic nervous system?
involved with emergencies e.g. fight or flight
what is parasympathetic system?
involved with restoring natural order, relaxing after an emergency
e.g. rest or digest
what is a sensory neuron?
carries impulses from sensory receptors (e.g. touch, vision and taste) to the spinal chord and brain
what is a motor neuron?
can be found in the motor cortex, responsible for indirectly/directly controlling muscles.
what are relay neurons?
a link between motor and sensory neurons for faster reactions.
describe synaptic transmission
hint: its fucking long
info is passed down the axon of a neurone as an electrical impulse known as action potential. when the electrical impulse reaches the end of the neurone it triggers vesicles to release neurotransmitters across the synapse. These then bind to receptor sites on the post-synaptic cell which then become activated.
what are the two possible neurotransmitters?
exhibitor and inhibitory neurotransmitters
what are excitatory neurotransmitters?
the nervous system’s ‘on switch; e.g. adrenaline. Causes excitation in the post synaptic neuron by increasing the positive charge and making it more likely to fire
what are inhibitory neurotransmitters?
the nervous system ‘off-switch’ causes inhibition by increasing the negative charge and making it less likely to pass on the electrical impulse e.g. serotonin
what is the endocrine system, and how does it differ from the CNS?
seperate from the nervous system it using blood vessels to deliver hormones to target sites in the body. it is slightly delayed and longer lasting in comparison to the nervous system.
role of the endocrine system?
to maintain homeostasis
describe how a hormone is released from a target gland.
hint: it’s fucking long
hypothalamus sends releasing hormone to pituitary gland which then secrets a ‘stimulating hormone’. Target gland releases its hormone in response and therefore levels of the targets gland hormone increases in the bloodstream. Hypothalamus stops secreting releasing hormone along with the pituitary gland ceasing secretion of the ‘stimulating hormone’.
describe the fight or flight response through the endocrine systems.
hint: sorta long
the hypothalamus triggers pituitary gland to release ACTH. This activates the sympathetic ns which then causes the adrenal medulla to release adrenaline, triggering the fight or flight response.