Kin 256 2A

• 1. Glucose
• 2. Ketone bodies

• 1. Fatty Acids
• 2. Ketone Bodies= Glucose

• 1. Fatty Acids
• 2. Ketone Bodies
• 3. Lactic acid= glucose

• 1. Fatty Acids
• 2. Glucose= Ketone bodies= Lactic acide

signal diffuses to nearby target cell

Signal substance effects secretory cell

neuron's axon terminal secretes neurotransmitter, diffuses to postsynaptic cell (through the synapse)

endocrine glads secretes hormone into blood and reaches target cell through circulatory system

seperation of charged ions across a membrance cause this

Anions attract cations and vice versa

in nerve and muscle tissue

These are called voltage-gated  ion channels

when the intracellular environment is negative mV

when the intracellular environment is positive mV

Example, sodium ion can enter the cell

neurotransmitters bind to ligand-gated ion channels in nerve and muscle tissue

signal triggering molecule 

    Ex. hormone, neurotransmitter or other

When ligand is attached to receptor, movement occurs down the concentration gradient

act through a second messenger system and usually linked to a G protein

extracellular ligand, binds to specific plasma membrane protein receptor > activates and intracellular G protein causing a signalling cascade.

starts cascade

amplifies the signal by activating further enzymes in a pathway

-20 to -200 mV

-70 mV

-95 mV

K+>> Na+

Ca++ concentration outside the cell is much greater than inside the cell

much greater inside the cell

Always open, relatively uncommon

pumps 3 Na+ out of cell and 2 K+ in to regulate resting membrane potential 

1 ATP used

pump Ca++ out to regulate resting membrane potential

negative mV at rest

active transport of ions against concentration gradient

positive change in mV> cell becomes activated

transmit nerve impulse as action potentials

Dendrite > cell body> axon

• support neurons
•      Schwann cells 
•      Oligodendrocytes

produce myelin sheath of PNS

• form myelin sheath of of CNS
• "white matter"