Topic 8

• • The experimental kitten had fewer

  synaptic connections

  • between neurons associated with

  the right eye.

  • Left ocular Dominance columns

  contained more synapses to

  compensate.
• When light intensity increases


  The current produced by rod cell decreases
• Reason for decreased current

  Rhodopsin is broken down, opsin gets released
• What happens when more opsin is released

  1. More opsin binds to sodium-gated voltage channels

  2. Sodium-gated voltage channels close

  3. Reduces the influx of sodium ions
• How an impulse passes across a synapse

  1. Ca2+ enter presynaptic neuron

  2. Vesicles containing NTMs fuse with pre-synaptic membrane

  3. NTM molecules diffuse across the synapse

  4. NTM binds to receptors on post-synaptic membrane

  5. Na+ diffuse into post-synaptic cell, depolarising the membrane
• • IAA causes cell elongation

  • IAA alters pH of cell wall

  • IAA stimulates root growth
• • use a microscope + allow Daphnia to

  acclimatize

  • record heartbeat before + after placing in

  regular/caffeinated coffee

  • controls

  • use statistical test