Central Nervous System

Question 1

Sensory Neurons (Afferent)

Answer 1

• receive and carry info from sensory receptors to brain and spinal cord (CNS)

Question 2

Motor Neurons (Efferent)

Answer 2

• carry messages from the brain to skeletal muscles

Question 3

Inter Neurons

Answer 3

• transmits messages between sensory and motor neurons, primarily in the CNS

Question 4

Spinal Cord

(3)

Answer 4

• information highway connecting PNS to brain
• ascending neural fibres send up sensory info from body to brain
• descending neural fibres send down motor-control info from brain to body
  (via PNS)

Question 5

Spinal Reflex

Answer 5

• involuntary, innate reactions in the form of automatic, swift movements in response to external stimuli

Question 6

Spinal Reflex Pathway (2)

Answer 6

• only travels to spinal cord not brain therefore faster
• information splits at the inter neuron in spinal cord to the brain

Question 7

Monosynaptic Reflex

(3)

Answer 7

Sensory –> Motor
- involves only one synapse (no inter neuron)
e.g. knee-jerk/patellar reflex

Question 8

Polysynaptic Reflex

(3)

Answer 8

Sensory –> Inter –> Motor
- involves more than one synapse
e.g. pain/hand-withdrawal reflex