8A Brin Flashcards
What does the left hand side of the brain receive
Control the right hand side of the body
What’s does right hand side of the brain receive
control the left hand side of the body
What does the cerebrum control
Responsible for muscle coordination and movement
- carry conscious activities
-vision
-hearing
-speech
-thinking
-memory
Hypothalamus role
Thermoregulation
Monitors blood temperature and initiate a homeostatic response if temp. Too high or too Low
Osmoregulation
Monitor the water balance of the blood and release the hormone ADH if the blood becomes too conc.
—> ADH increase absorption of water in the kidney
Controlling pituitary gland
To release hormones to control a variet of processed
Regulating digestive activity
Regulate the hormones that control appetite as well as the secretion of digestive enzyme
Role of pituitary gland
Anterior pituitary produces and release hormones
Posterior pituitary store and release hormones produced by the hypothalamus
Role of cerebellum
Coordinates movement
Control balance and maintain posture
-balance
—> multiples parts eyes, semicircular canals in the ear
Role of medulla oblongata
Contains co-ordination centre that control different unconscious function
- cardiac centre - controls heart rate
-respiratory cente controls breathing rate
Breathing rate
Blood pressure
Coughing
Swallowing
Saliva production
Eyes in dim light on the muscle
Circular muscle relax
Radial muscle contract
Eyes in dim light on the pupil
Dilated
Bright light on the eyes
Circular muscle contract
Radial muscle relax
Bright light on the eyes pupil
Constricted
Parasympathetic nervous system on the preganglionic fibre
Long myelinated
Parasympathetic nervous system on the postganglionic fibre
Short unmyelinated
Parasympathetic system on the organ system
Slower calmer or inhibitory effect on the organ system
Parasympathetic nervous system
Rest and digest
Feed and breed
Parasympathetic nervous system what neurotransmitters it produces
Neurotransmitters acetylcholine at the synapse
Parasympathetic nervous system where is the ganglia near to
Ganglia are near to or in the effector organ
Sympathetic nervous system where is the ganglia near to
CNS
Sympathetic nervous system preganglionic fibre
Short myelinated
Sympathetic nervous system postganglionic fibre
Long unmyelinated
Sympathetic nervous system
Active, under physical and psychological stress
Fight or flight
What sympathetic nervous system neurotransmitters produce
Produce the neurotransmitters NORADRENALINE at the synaptic
How does CT scan work
X ray to produce a cross section image
A beam of x ray is aimed at a patient from all angles around the body
Digital x ray detector are used to pick up the x ray as they exit the patient body
Denser tissue absorb more of x ray radiation so show up a lighter region on a
Usage of CT
Identify and detect problems such as brain tuners , bleeding in the br aneurysm
Advantages of CT
Physical structure of the brain and allows visually Saigon of any tissue damage
—> infer they function of the different egions of the brain by matching a patient symptoms with the areas of the brain damage
CT disadvantage
Don’t show the function of the region but - possible to link symptoms with the location of any tissue damage
Not recommend for pregnant patient or children to risk of exposure to x ray radiation
Less detail and risk of x ray
How does MRI work
Use magnetic field and radio waves to image the soft tissue
Advantages of MRI
Soft tissue can be seen MRI, and images produced at a higher resolution
More details —> fineee detailed
MRI allow you to clearly see the difference between normal and abnormal
Less risk than CT scans (no use X-ray )
—> safer thus less risk of cell damage,mutation
MRI disadvantage
Function of brain regions can be inferred by matching up a patient symptoms with areas of brain damage
Noisy and patient must keep their head completely still
MRI usage
Different tissue respond differently to the magnetic field
Computer put the slices (2D image) to produce 3D image
How does fMRI work
Deoxyhaemoglobin absorb the radio wave signal and later remits it
More oxygenated blood flows to active areas of the brain to supply the neurone with oxygen and glucose
Molecules in oxygenated blood respond differently to a magnetic field than those in deoxygenated blood the signal returned to the scanner is stronger from the oxygenated blood which allows more active areas of the brain to be identified
How it works
Monitor the absorption of oxygen in different brain areas
-deoxygenated absorb the radio waves and remits it but oxyhaemolobin does not = less re-emit of signal from active areas because it is oxygenated blood that is being supplied
fMRI advantages
High resolution
MRI and fMRI scan allows brain function to be studied in real time
If a function is carried out whilst in the scanner the part of the brain that involved with that function will be more active
Damaged or diseased areas of the brain and allow you to study condition caused by abnormal activity
fMRI disadvantage
Noisy procedure - cause ppl to be stressful
Must keep their head completely still cuz any movement reduces the accuracy of the image
~~argument over that blood flow to different areas of the brain when a subject is looking at different stimulus is a case of correlation not causation
how does PET work
Radioactive tracers collect in areas where there is increased blood flow , metabolism or neurotransmitters activity
Which region of the brain are activated at any given time but they use radioactive tracers such as radioactivity labelled glucose
The radioactively labelled glucose will accumulate in parts of the brain which are and will produce a stronger signal
PET advantages
High resolution and high quality
Both structures and function of the brain in real time
Gives 3D images
The scanner can detect areas of high radioactivity and so the movement of the tracer through the body and any accumulation of tracer in the brain can be seen
—> indicate whether that region is active or inactive
PET disadvantage
Patient gets injected with a rdiotracer (radioactive isotopes)
What is a blood brain barrier
Is a barrier formed by the endothelial cells that lie the capillaries of the brain which are tightly joined together making it difficult for bacteria or therapeutic drugs to enter the brain
What could be Parkinson disease
Could be genetic factor or environmental factors( toxins, herbicides and pesticides)
What part of the brain caused damage to Parkinson disease
Loss of nerve cell in substantia nigra which produces dopamine as neurotransmitters = no dopamine production from this area
What is substantia nigra involved in
Control and coordination of movement
Symptoms Parkinson disease
Tremor
Slowness of movements
Stiffness of the muscle
Poor balance
L dopa
Can cross the blood brain barrier
L-dopa can be converted into dopamine
Supplying the brain with L dopa allows the remaining cells to make as muscle dopamine as possible
Reduce stiffness and slow movement
Dopamine agonists
Produce the same effect as mimic dopamine by binding to and activating dopamine receptors on the post synaptic membrane
Enzyme inhibitors (MAOB)
Monamine oxidase B (MAOB) inhibitors inhibits the activity of enzyme that would normally breakdown dopamine in the synaptic cleft raising levels of dopamine present in the brain
1)Inhibits the enzyme which cause the breakdown of neurotransmitters in the synapses form the brain
2)more neurotransmitters remains in the synaptic cleft
3)more impulses travel along the post synaptic axon
4)reduce symptoms by producing a more positive mood
How does gene therapy relate to Parkinson disease
Involve in addition of genes to the affected cells in the brain to either increase dopamine production or prevent the destruction of dopamine-producing cells
How does stem cell therapy relate to Parkinson disease
Stem cell could be used to replace the lost dopamine-producing cells in the brain
Why ecstasy cause depression
How does ecstasy work
1) ecstasy blocks the serotonin reuptake transport system so that synapse are completely flooded with serotonin which cannot be returned to the presynaptic knob
2)stimulate the release of serotonin in the presynaptic knob into the synaptic which affect the postsynaptic membrane and flood the brain with impulse
3)dopamine system are affected with the high level of serotonin stimulating the release of more dopamine
What is ecstasy
Act as a stimulant
Increase heart rate
Psychotropic drug
—> causes a change in mood
—> alter the way people see the world
What effect ecstasy
Increased heart rate
Body is unable to regulate its temp.
No desire to drink hence causing hyperthermia (overheat)
—> raised blood pressure
—> irregular heart beat
Death may result
Affect the hypothalamus—> secrete more ADH—> more water reabsorption —> more conc urine(less volume of urine)
What is SSRI
SSRI inhibits the reputable of protein in the presynaptic membrane so more serotonin remains in the synaptic cleft more impulse travel along the post synaptic axon to relieve the symptoms
Example of SSRI PROZAC
1) it inhibits the reputable transporters
2)more serotonin remains in the synaptic cleft
3) more impulses travel along the post synaptic axon
4)reduces symptoms by producing more positive mood
Causes of depression
Low levels of neurotransmitters of serotonin
Symptoms of depression
Feeling of intense sadness
Loss of interest in pleasureable activities
Low self esteem
Low energy level
FUNCTION OF SSRI (SELECTIVE SEROTONIN REUPTAKE INHIBITORS)
Ssri inhibits the reuptake proteins in the presynaptic membrane so more serotonin remains in the synaptic cleft more impulse travel along the post synaptic neurone axon to relive symptoms
Effect on SAN sympathetic
Stimulate SAN
Increase frequency of signal
Effect on SAN parasympathetic
Inhibit SAN
Decrease frequency of signal
Sympathetic effect on heart rate
Speed up heart rate
Parasympathetic heart rate
Slow down heart rate
