13.2 Nervous System Flashcards
Neurobiological reserach on nervous system made on…
Giant squid (axon up to 1mm in diameter)
The function of the nervous system is to?
Produce behaviour
3 tasks performed by nervous system?
- Detection and analysis of sensory signals
- Decision making
- Generation of coordinated motor output
Nervous system in…
A) Sea anemone?
B) Earthworm + squid?
C) Human?
A) Nerve net
B) Ganglia + nerves
C) CNS + PNS
Nervous systems consist of nerve cells and….
Glia (electrical isolation or nerve cells + blood-brain barrier + uptake of transmitter)
Role of neurons?
Generate and transmit electrical signals
Role of glial cells?
Provide nutrients, oxygen, maintain extracellular environment, make the bloodbrain barrier, fight infections, insulate neurons
Which is more present - neurons or glial cells?
Glial cells (5-10x)
How do neurons work?
Electrochemically
What prevents the free movement of ions?
Lipid biulayer
What control the ion flux across the membrane?
Ion channels and ion transporter proteins
Typical ion concentration - intracellular?
A lot of K+, a medium amount of Na+, a bit of Cl-, a lot of A-
Typical ion concentration - extracellular?
Little K+, lots of Na+, lots of Cl-, no A-
What is the membrane potential?
The electrical potential difference across membrane
What is the resting potential?
-65 mV