Paper 1- The Brain + Problems Flashcards
What is the cerebral cortex and its function ?
-The cerebral cortex makes up about 80% of the brain.
-cerebral cortex is responsible for personality - past idea. Phineous gage had a rod go thorough his brain. He went from hard working to lazy and friendly to mean. Aristotle believed the brain cooled the body.
-due to technological advances we know it is responsible for major movement, senses, language, memory, behaviour and consciousness.
-made up of two cerebral hemispheres. Right controls left side of the body and vice verca
What are the functions of the cerebellum ?
At the base of the Brain is the cerebellum. It is divided into two halves.
-balance, posture, co ordinates timing, fine control of muscles.
-musicians have developed an increase in size in the cerebellum due to extensive use of it.
What are the functions of the medulla oblongata ?
-controls heart rate and breathing rate. Responsible for reflexes such as sneezing, vomiting and swallowing. “Auto pilot” part of the brain.
What are the functions of the spinal cord ?
The mass of neurones that make up the oblangata connect the brain to the spinal cord.
-it is about the width of a finger and consists of many nerves, these Carry information between the brain and the rest of the body.
What is a nerve ?
A bundle of neurones (aerobic respiration)
(WORKED EXAMPLE) someone who has broken their spinal cord is paralysed from the neck down. Explain why.
Never impulses to and from the lower part of the body pass through the spinal cord. If these nerves are damaged, there is no way that impulses can be sent between the brain and the rest of the body. Wires can reconnect the spinal cord, but not very effective.
What happens during brain surgery ?
Electrodes applied to the brain, current activates parts if the brain
What happens in a ct scan ?
CT scan used to show shapes of structures in the brain.
-patient given radioactive tracer which allows parts of the brain to show up.
- x ray moves around the head. Detector measures x ray absorption and creates image/slices of 3d image denser. (Images put together to create 3d image)
-material = more x rays absorbed = white area on ct scan = possible tumour.
What happens in a PET scan ?
PET scan shows brain activity, not structure.
-patient is given a small amount of a radioactive form of glucose.
-travels to parts of the body where respiration is occurring rapidly
-radioactive glucose creates gamma rays, which the scanner detects.
-more gamma = more glucose used = more active. (Builds up images of where tracer is most concentrated)
-can be useful to show over active or under active parts of the brain.
Spinal cord damage based on location affected.
Damage lower down = loss of feeling/ use in legs
Damage in neck = quadriplega (loss of arms and legs). Can’t repair damage as adult stem cells cannot differentiate into neurones. - possible to use embryonic stem cells? Can stimulate nerves using electrodes but doesn’t fully heal/go back to normal
How can doctors study brain damage ?
By studying patients with brain damage, where part of their brain doesn’t function, neuroscientists have been able to link particular regions of the brain to particular functions.
Why is brain damage permenant
Neurones cannot be replaced unlike other cells (stem cell research).
Why are brain tumours so dangerous to the brain as a whole ?
They can block blood flow to other parts of the brain
These cancers can be treated with chemotherapy (using drugs), radiotherapy (using radiation) or brain surgery, but these also cause lots of damage to the body (partially effective).
