Topic 2 Flashcards
What is the function of the myelin sheath?
Covers the dendrons and axons
Electrically insulates a neurone from neighbouring neurones, stopping the signal loosing energy
Speeds up the NEUROTRANSMISSON as it makes the impulse jump along the cell between the gaps in the myelin
What is the travelling of impulses called?
Neurotransmission
What is the function of a sensory neurone?
To carry the impulse from the receptor cells to the CNS
What structural features does a sensory neurone contain
Dendrites
Dendron
Cell body
Axon
Axon terminals
Why may Chemotherapy not work?
Blood-brain-barrier’ –> a natural filter that only allows certain substances to get from the blood into the brain
Methods of treating a tumour?
Radiotherapy - high energy x ray beams
Chemotherapy - injected drugs that actively kill dividing cells
Limitations of spinal cord injuries?
There are no adult stem cells that an differentiate into neurones in the spinal cord, so new neurones can not replace the old damaged one
How is a PET scan done?
Patient is injected with radioactive glucose
More active cells take in more glucose, such as tumour cells
The radioactive glucose causes gamma rays which can be picked up on a scanner
What does a PET scan show?
Brain activity
How does a CT scan work?
x-rays beams through the head, a doctor measures the absorption
Denser materials absorb more x-rays which shows up as a white area, e.g. bones
breaks appear dark when should be white
What does a CT scan show?
Shape and structure of the brain
What does the medulla oblongta control?
Reflexes
Breathing rate
Heart rate
What does the cerebellum control?
Balance
Posture
Fine control of muscle activity
What does the cerebral cortex control?
Language
Memory
Senses
Behaviour
Consciousness
What are three parts of the brain?
Cerebral cortex
Cerebellum
Medulla oblongta
