What does the cerebellum do?
- coordinates posture, balance and movement
- sensory input comes from muscles, joints, eyes and ears
- analyses, then works with motor in cerebrum to produce a centre response.
- thought to be involved in learning and languages
What does the hypothalamus control?
- appetite and thirst
- body temp
- circadian rhythm
- sexual behavior
What does the thalamus control?
- recognition of pain
- relays and redistributes from most of the brain to cerebral cortex
What is the diencephalon?
- Connects cerebrum with brain stem
- also has thalamus and hypothalamus
What are the 5 different lobes?
- Frontal- motor areas, motor speech, intellect, judgement behavior and prediction
- Parietal- awareness of movement and position
- temporal- sound of interpretation, smells
- occipital- visual perception and association
What is the inner part of the cerebrum made of?
lots of nerve fibres- nerve tracts (white matter)
How is the cerebral cortex designed?
- Many ridges and folds
- increases surface area
- increase number of cells in the brain
What is the outer cerebrum called? and what is it composed of?
- cerebral cortex
- composed of grey matter (nerve cell bodies)
what is the cerebrum divided into? and what are they connected by?
- 2 hemispheres R + L
- connection (corpus callosum) formed by nerves
What is the largest part of the brain?
what are the 4 parts of the brain?
- brain stem
how much glucose and o2 does the brain use?
what colour are the cell bodies and axons?
- cell bodies- grey
- axon- white
what do the nodes of ranvier assist in?
rapid transmission of impulses
what is myelin sheath formed by?
concentric schwann cells
what do axons and dendrites do?
- axons carry impulses away from cell body
- dendrites carry impulses towards cell body
what is a neuron?
- each cell has:
- 1 cell body
- 1 axon
- many dendrites
what are the 2 nerve tissues?
- neurone- generate and transmit impulses- bundles called nerve
- neuroglia- supporting structure
what is the peripheral nervous system?
- all the nerves outside the brain and spinal cord
- sensory (afferent)- impulses from body to CNS
- Motor (efferent)- impulses from CNS to body
what is the central nervous system?
- brain + spinal cord
- 1) receives sensory information from nerves
- 2) analyses and processes the information
- 3) responds by sending a impulse via nerves to the body
what are the two different types of system?
- central nervous system (CNS)
- peripheral nervous system (PNS)
what is the purpose of the nervous system?
- detects and responds to changes inside and outside the body
- helps coordinate and control vital aspects of body function
- maintains homeostasis
what is the brain stem divided into?
- mid brain
- pons varolli
- medulla oblongata
What does the brain stem control?
levels of consciousness
What does the brain stem control?
origins of cranial nerves
What does the midbrain and the pons consist of?
- nerve fibres
- acts as relays between different parts of the brain
What are the clumps of nuclei in the Pons called?
- pneumotaxic centre and apneustic centre
- work together with the respiratory centre in the medulla to control respiration
what is the medulla continuous with?
What 3 centres are in the medulla?
What does the cardiovascular centre control?
- rate & force of contraction
What does the respiratory centre control?
- rate & depth of respiration
- nerve impulses pass to phrenic and intercostal nerves
What does the reflex centre control?
- all reflexes that are activated in the medulla in response to irritants
What crosses over in the medulla before they get to the spinal cord?
- motor nerves descending from the motor area of cerebrum.
- left hemisphere controls right of the body
- Right hemisphere controls left side of the body
Where do the cranial nerves originate?
nuclei in the base of the brain
how many pairs of nerves in make up the cranial nerves?
Which nerve leaves the head and neck?
vagus nerve (the wanderer)
What is the spinal cord continuous with?
how long and what is the diameter of the little finger?
Where does the spinal cord extend down to?
What is it called when the spinal cord stops being a solid structure and fans out? where does this happen?
What are the three layers of the meninges?
- Dura mater
- arachnoid mater
- pia mater
Describe the dura mater
- tough double layer lining the skull and the brain & cord
- potential space in between
describe the arachnoid mater
describe the pia mater
- delicate layer
- adhering to the brain & cord with multiple blood vessels
what are the three spaces called?
How many ventricles are there in the brain?
What is CSF?
what is secreted into each ventricle?
What specialised cells secrete CSF and what rate is is secreted at?
- choroid plexuses
- 0.5 ml per minute
Where does the CSF flow from the ventricles?
- subarachnoid space
- flows around subarachnoid space surrounding the brain and the spinal cord
What is the CSF movement aided by?
- pulsating blood vessels
How is CSF absorbed?
by projections from the arachnoid mater (arachnoid villi)
What colour is CSF?
clear and colourless
What does CSF help maintain?
a uniform pressure around central nervous system
what does the CSF act as?
cushion/shock absorber between brain and skull
what does the CSF lubricate?
brain and cord
what does the CSF fluid exchanges?
nutrients and waste
What is the peripheral nervous system?
all the nerves outside the brain and spinal cord
how many pairs of nerves divide from the spinal cord to connect with the body
Where does the first pair of spinal nerves leave the vertebral canal?
occipital bone and 1st cervical vertebra
How many cervical, thoracic, lumbar, sacral and coccygeal nerves are there?
- 8 cervical
- 12 thoracic
- 5 lumbar
- 5 sacral
- 1 coccygeal
What does the Autonomic nervous system?
subconsciously controls body functions and homeostasis
What do the specific ANS nerves effect?
- smooth muscle
- cardiac muscle
What is the ANS divided into?
- sympathetic nervous system
- parasympathetic nervous system
What does the sympathetic nervous system do?
- deal with stress
- fight or flight
What effects does the sympathetic nervous system have on the body?
- stimulates cardiac activity
- opens the airways
- dilates skeletal blood vessels
- reduces gastric activity
What does the parasympathetic do?
- general peacemaker
- rest and digest
what effect does the parasympathetic nervous system have on the body?
- stimulates digestion and absorption of food
- slows down cardiac and respiratory activities