Nervous system

Question 1

What is the NS

Answer 1

• controls all body systems and their communication function
• important in maintaining homeostasis
• Controls emotions actions and thoughts
• chemical and electrical signals
• Millions of sensory receptors- detect change- NS processes- effector e.g. muscle or gland

Question 2

what is the CNS and what is it split into

Answer 2

Consists of the brain, brain stem and spinal chord

Question 3

Describe the brain

Answer 3

The brain has 3 protective layers: dura, arachnoid and pita matter which make up the menengies, hence when there is an inflammation or infection it is called menigitis

Question 4

Cerebrum

Answer 4

The actual brain itself including the lobes
Made up of grey and white matter
Gray matter- made up of neurons, integrating information
White matter- Axons, out of the neurons, transporting information, insulated by fat making it look white

Question 5

Cerebellum

Answer 5

maintaining posture, balance and tone

Question 6

Cerebrum cortex

Answer 6

Where the lobes are located
- Frontal lobe: Site of motor cortex, movement
- Occipital lobe: site of visual cortex
- Temporal lobe: audiotory cortex
- Parietal lobe: somatosensory cortex

Question 7

Brain stem

Answer 7

• Home of the 12 pairs of cranial nerves
• Olfactory, Optic, Occulomotor, Trigimenal, Trochlear, Abducens, Facial, Vesticochlear, Glossopharngyl, Vagus, Accessory, Hypoglossal
• Made up of Pons, mid brain and medulla
• Important in cardiovascular and respiratory rhythms and reflexes e.g. blinking and coughing

Question 8

Spinal chord

Answer 8

Has 31 pairs of peripheral nerves
Made up of the thoracic, saccral, coyxcc, lumbar and cervical

Question 9

What is the PNS

Answer 9

PNS is split into autonomic and somatic nervous system

Question 10

What is the autonomic nervous system

Answer 10

• controls involuntar movements e.g heart contraction, hormone secretion
• split into parasympathetic and sympathetic
  -Parasympathetic: rest and digest-saliva production, heart rate decreases, pupils constrict
• Sympathetic: fight or flight response, heart rate increase, pupils dilate, ingestion inhibited

Question 11

What is the somatic nervous system

Answer 11

Voluntary movements
skeletal muscle movement e.g. singing dancing
Recieves sensory info from external environment

Question 12

Describe stages of neuromuscular junction

Answer 12

1. Depolarisation causes AP to travel down the neuron
2. Sodium channels open due to charge change
3. Influx of sodium
4. AP gets to end of neuron opening calcium gated channels
5. Calcium enters and tells the vesicles to bind with the presynaptic neuron
6. The vesicles release the neurotransmitters across the synapse- acetylcholine
7. These need to bind to specific receptors on the post synaptic neuron- nicotonic
8. These receptors cause sodium channels to open
9. Sodium to muscle cell
10. travel to t-tubules
11. Sodium depolarises causing the sarcoplasmic reticulum to release calcium
12. For muscle contraction: calcium and ATP