CNS Flashcards
What is the nervous system?
Receives, transmits and responds to info from external environment to internal environment through nerve cells (specialised cells that carry messages around body)
What is the CNS?
The brain and spinal cord - body’s control system
Spinal cord connects brain to every area of body through nerve cells
What is the spinal cord?
Bundle of nerve fibres and tissue that connects nearly all parts of body to brain - protected to vertebrae
What is the peripheral nervous system?
Any other nerves outside CNS
Relay info from brain + spinal cord to rest of body
Includes autonomic, sensory and motor nerves
What is the autonomic system?
Involuntary - don’t consciously control e.g. heart rate + gut movement
What are the sensory neurones?
Relate to sensation or physical senses - anything stimulating senses will be relayed to brain via sensory neurones
What are the motor neurones?
Relate to motion or physical activity
Transmit info from muscles to brain
What is the somatic nervous system?
Made up of sensory and motor neurones
Sensory and motor pathways have to work together, voluntary or involuntary
What is the role of the meninges?
Three layers of membrane surrounding brain + spinal cord - barrier from rest of body and infection
What is the role of the cerebral cortex?
Responsible for thinking, processing sensory info from body - 4 lobes have own functions
What is the role of the corpus callosum?
Bridge of nerve tissue that connects halves of brain and enables communication between hemispheres
What is the role of the hypothalamus?
Responsible for maintenance of temperature and appetite + thirst
What is the role of the medulla oblongata?
Automatically regulates life sustaining functions e.g. breathing and heart rate
What is the role of the cerebellum?
Coordinates and regulates muscle activity + controls muscles to maintain balance
What is the role of the fronal lobe?
Carries out higher level mental processes e.g. thinking and decision making
What is the role of the temporal lobe?
Responsible for processing auditory info - comprehend and understand language
What is the role of the parietal lobe?
Process info from taste, temperature and touch
What is the role of the occipital lobe?
Processes visual info
Where is the cerebellum found?
Back and bottom of brain
Where us occipital lobe found?
Back of brain above cerebellum
Where is temporal lobe found?
Bottom of brain in middle
Where is parietal lobe found?
Top of brain towards back
Where is medulla oblongata found?
Along brain-stem
What is the function of the dendrites?
Short branched structures that receives electrical impulses from other neurons and carry them towards cell body
What is the function of the cell body in neurons?
Where nucleus is found -controls neuron activity
What is the function of the axon?
Long thread like part of nerve cell - impulses conducted away from cell body to other cells
What is the function of the nodes of ranvier?
Action potential will start to lose charge as it travels down the axon - gaps allow positively charged ions to flood into axon and boost charge of action potential
What is the function of the myelin sheath?
Produced by schwann cells
Fatty white substance surrounding axon
Protective insulating layer to prevent impulses leaking
Enables impulses to transmit quickly along axon
What is the function of the axon terminal?
End branches of axon - pass messages to next neuron by triggering impulse of neurones dendrites to release neurotransmitters that pass messages between neurons
What is action potential?
The electrical signal being sent through the neuron
What happens to cerebellum when you drink alcohol?
Cerebellum controls balance and fine motor action - message sent from motor cortex to cerebellum and back again before sent to muscle fibres - alcohol disturbs signals - loss of coordination
What is the function of a synapse?
To transfer electric activity from one cell to another
What 3 elements does synapse consist of?
The pre-synaptic membrane, post-synaptic membrane and synaptic cleft (gap in middle)
What is the function of the synaptic cleft?
Gap between pre-synaptic membrane and post-synaptic membrane
What is the function of the mitochondria in synapse?
Provide energy to cell - ATP -> ADP = energy
What is the function of the neurotransmitters?
Chemical messengers released at axon terminal - send electrical signals between neurons
What is the function of the receptors in synapse?
Binding site of neurotransmitters
Embedded in membrane of post-synaptic membrane
Bind with neurotransmitters to trigger electrical impulse and carry it along neuron
What is the function of the enzymes in synapse?
Stop transmission between neurons - break down neurotransmitters in synaptic cleft to be reabsorbed into post-synaptic neuron and used again
