Theme 1

Question 1

What are the divisions of the ANS?

Answer 1

Sympathetic: fight or flight response. Getting ready for surge of adrenaline to start doing something

Parasympathetic: rest & digest - relaxed state, such as salivary production when thinking of food

Question 2

Grey Matter

1. Role?
2. Consists of?

Answer 2

1. Interpreting signals
2. Neuronal cell bodies & Dendrites: short projections at bottom of nerve body which conducts to cell body

Astroglia: many support roles such as nutrients, ion balance and repair

Microglia: defence cells removing infection and damaged cells

Question 3

White matter

1. Role?
2. Consists of?
3. Colour different

Answer 3

1. Sending signals

2.
Myelinated axons: result in signals moving more faster, move from the system faster – thicker nerves

Oligodendroglia: produces the myelin sheath around neurones

Microglia

3. contains fewer cell bodies and instead long myelinated axons = white

Question 4

What type of glial cells are essential in providing neurones with nutrients and structure?

Answer 4

Astroglia

Question 5

What type of cells provide an active immune response in the central nervous system?

Answer 5

Microglia

Question 6

In terms of function, how do Oligodendrocytes differ to Schwann cells?

Answer 6

Oligodendroglia produces the myelin sheath around neurones and as apposed to Schwann cells that can do it for multiple nerves in a certain area.

Question 7

What do the following keywords stand for?

• Ipsilateral
• Contralateral
• Ascending/Efferent
• Descending/Afferent
• Somatic
• Visceral

Answer 7

Ipsilateral: Same side

Contralateral: Opposite side

Ascending/Efferent: to brain (e.g. sensory fibre)

Descending/Afferent: away from brain

Somatic: Conscious & voluntary movement

Visceral: Background & involuntary movement

Question 8

Name the Lobes of the brain and give an overview of their function

Answer 8

Frontal: problem solving – thinking

Parietal: interpretation of signal, e.g. taste, smell, hearing and touch

Occipital lobe: Vision, e.g. colour, interpreting signal from both eyes

Temporal lobe: memory

Question 9

What are the 3 main nerve fibres in teeth?

Answer 9

A-beta: light touch and proprioception
- If something was stuck in the teeth

A-delta: respond to noxious stimuli with short sharp pain
Extend out of pulp into dentine, first fibres to be stimulated
Myelinated = fast

C-fibres: unmyelinated, responsible for dull aching or burning pain

Question 10

What are the different sulcus present in the brain?

Answer 10

Parieto-occipital: separates parietal and occipital lobes

Lateral sulcus/Sylvian fissure: separates temporal and lateral lobes

Question 11

What are the different important gyrus on the lateral aspect of the brain?

Answer 11

Pre-central gyrus: primary motor cortex  contralateral hemispheres

Post central gyrus: somatic sensory context  contralateral hemispheres

Occipital pole: on medial surface we have the Primary visual cortex  contralateral hemispheres – found on calcarine sulcus (usually in the depth of)

Inferior frontal gyrus = Broca’s area: Language output area

Inferior of lateral sulcus between TL & PL (SUPERIOR TEMPORAL GYRUS) = Wernicke’s area

Question 12

What are the different structures found on the mid-sagittal section of the brain?

Answer 12

Thalamus: relay centre – all sensory information from body will go via thalamus to the cortex

Hypothalamus: monitors internal environment and triggers a response

Pituitary gland: Hormone release under control of the hypothalamus

Pons: bridge between brain and spinal cord

Corpus callosum: connects two hemispheres together

Question 13

Approximately where are the different cranial nerves found?

Answer 13

Midbrain = 2 posterior cerebral – superior cerebellar
CN 3 & 4

Pons = 4 basilar
CN 5,6,7,8

Medulla = 4 vertebral
Cn 9,10,11,12

Question 14

Describe the development of the brain

Answer 14

Neural plate –> Formation of the neural crest & Neural fold = neural groove

Question 15

What does the neural crest form?

Answer 15

Migrate out and form derivatives, nervous type tissues – forming peripheral nerve tissues

Question 16

What is a Neural Tube Defect, and list some diseases caused by neural tube defects.

Answer 16

failure of the neural tube to close, resulting in diseases such as anencephaly and spina bifida

Question 17

How might the NHS help prevent Neural tube defects occurring?

Answer 17

Providing pregnant mothers with folic acid supplements

Question 18

Name the three primary vesicles of brain development in utero.

Answer 18

Prosencephalon
Mesencephalon
Rhombencephalon

Question 19

Name the five secondary vesicles of brain development in utero, and the structures of the brain they become.

Answer 19

Telencephalon- Cerebral hemispheres + lateral ventricles

Diencephalon- Thalamus + Third ventricle

Mesencephalon- Midbrain + Aqueduct

Metencephalon - Pons, Cerebellum + Upper part of fourth ventricle

Myelencephalon- Medulla + lower part of fourth ventricle

Question 20

Damage to the occipital lobe of the brain may result in what changes?

Answer 20

Loss of vision, blurred vision, general visual impairment.

Question 21

A patient presenting with difficulty in understanding spoken/written language likely has damage to what part of their brain?

Answer 21

Wernicke’s area + Brocke’s area

Question 22

What are the two major arterial blood supplies to the brain?

Answer 22

Vertebral arteries + Internal Carotid arteries

Question 23

The basilar artery is supplied by which of these arterial blood supplies?

Answer 23

Vertebral arteries

Question 24

Of the arteries of the circle of willis, which supplies blood to the retina and cranial dura?

Answer 24

Ophthalmic Artery

Question 25

What arteries from the circle of willis are branches of the internal carotid arteries?

Answer 25

``` Ophthalmic Artery Posterior Communicating Artery Anterior Communicating Artery Anterior Choroidal Artery Anterior Cerebral Artery Middle Cerebral Artery ```

Question 26

What arteries from the circle of willis are branches of the Vertebral Artery? (& List branches of the Basilar artery

Answer 26

Ant. Spinal Artery Post. Spinal Artery Post. Inf. Cerebellar Artery ``` ---> Basilar Artery Ant. Inf. Cerebellar Artery Pontine Arteries Sup. Cerebellar Artery Labyrinthine artery --> Posterior Cerebral Artery ```

Question 27

Name the 3 main arteries that supply the cortex

Answer 27

Posterior Cerebral Middle Cerebral Anterior Cerebral

Question 28

What is Cerebrospinal Fluid produced by?

Answer 28

Choroid Plexus (70%) + Ependymal cells found in the epithelium of the ventricles (30%)

Question 29

What is Cerebrospinal Fluid composed of?

Answer 29

Protein, Glucose, and ions

Question 30

List four uses of Cerebrospinal Fluid.

Answer 30

1. Allows brain to ‘float’ – reduces traction on nerves and blood vessels connected to brain 2. Protective – cushioning 3. Removes waste metabolites 4. Stable ionic environment for CNS

Question 31

What are the two major ways in which a stroke develops?

Answer 31

Ischaemia (blockage) - 85% = lack of oxygen to the brain Haemorrhage (bleeding out of artery) - 15% = blood vessels stiffen and so they cannot stretch and cannot withstand pressure – bursting

Question 32

1. What are aneuisms? | 2. How can aneurisms harm the body?

Answer 32

1. Aneurysms are little pockets that form in the junctions of the circle of Willis, that burst 2. The chemicals from the burst blood can cause havoc with the nerve cells in the brain

Question 33

Blockage of which artery in the circle of willis would result in locked in syndrome?

Answer 33

Basilar Artery

Question 34

Why would this blockage result in locked in syndrome?

Answer 34

It would damage the pons as: Pontine arteries branch off the basilar artery at several points and act as the blood supply to the pons. Since the pons is the route for all ascending and descending pathways, if it is damaged it will result in paralysis.

Question 35

What is the difference in roles for Brocas & Wernicke's areas?

Answer 35

Brocas: production of speech Wernicke's: comprehension of speech