January 2022

• function of cilia


  move/beat/expel. The mucus/pathogens
• pathway from RER to plasma membrane

  RER -> transport vesicles -> GA -> transport vesicles -> plasma membrane
• Explain why fast twitch muscle fibers have higher concentration of glycogen than slow twitch muscle fibres

  - glycogen contains many glucose molecules

  - glucose partially broken down

  -so more glucose molecules needed

  - (referring to fast only) - uses anaerobic respiration

  - no mitochondria

  -less ATP produced per glucose molecule net gain of 2 ATP

  - reduced blood supply requires higher glycogen store to release the glucose that was NOT received from the blood
• Function of SER


  - makes steroid hormones

  - involved in carbohydrate metabolism

  - regulates calcium ion concentration in muscle cells

  -absorption and transports lipids from gut
• At. -55mv


  - threshold

  - all or nothing response

  - positive feedback

  - action potential occurs

  - more volted gated sodium ion gates open
• At point 1

  - -70mv

  - resting potential

  - concentration of sodium ions greater outside axon

  - sodium potassium pump operating 3 Na+ out for every 2 K+ in

  - inside of axon negative

  - more positive ions outside of axon are polarised
• Between point 1 and -55mv

  - sodium channels open

  - permeability to sodium ions increases

  - depolarisation occurs

  -sodium ions enter axon by diffusion

  - increased / changed membrane potential from -70 mv to -55mv