other

Question 1

what’s organelle in the soma is found near synapses

Answer 1

mitochondria

Question 2

which type of transmission (electrical or chemical) is more common in mature neurons;
compare electrical and chemical signals

Answer 2

chemical;
electrical provide fast, but shorter lasting transmission;
where as chemical convert electrical signals –> chemical –> and then back into electrical signals; these are slower acting, but longer lasting mech’s; can also amplify electrical signals;

Question 3

what is the benefit of a gap junction in a electrical synapse

Answer 3

it allows for direct continuation of intracellular space & ionic current

Question 4

what kinds of signals can neurons send? what signals can they receive?

Answer 4

they can send electrical;
can received both electrical and chemical

Question 5

what are the classes of glia; functions?

Answer 5

astrocytes - maintain chemical environ’ for neurons/synapses; can do everything expect create an AP;
oligodendrocytes - form myelin by wrapping around axons in the CNS; schwann cells do the same for cells in the PNS;
microglia - remove debris and secretes mole’s that help the immune system (inflammation, pruning cells or not);

Question 6

what is the difference between oligodendrocytes and shwann cells?

Answer 6

• each shwann cell serves as myelin by wrapping around one axon at a time, whereas oligo’s has one cell that has multiple processes that wrap around multiple axons

Question 7

Compare grey and white matter;
why are there more grey matter in cervical and lumbar regions of the spinal chord

Answer 7

white matter has more myelination;
because there’s a more concentrated amount of motor cells communicating (responsible for moving hind legs and forearms)

Question 8

compare ganglia to nucleus

Answer 8

• ganglia: local groups of nerve cells bodies & support cells;
• nucleus: local groups of like minded neurons; (neurons w similar functions & connectivity)

Question 9

how can we record neural signals?

Answer 9

• extracellular (**), intracellular(Can record multiple signals), and whole patch recording(Can record specific signals, graded potentials)

Question 10

which ions contribute to the resting membrane potential and AP amplitude?

Answer 10

K = resting;
Na = AP amplitude;

Question 11

at resting potential, which concentration are higher extracellularly?

Answer 11

• Na & Cl are higher extracell’
• K and A are higher inside

Question 12

• what was discovered from the voltage clamp method;
• what limitations did it overcome?

Answer 12

• allows to control membrane potential and measure both potential and permeability
• they found when they depolarized the membrane, that the first half of the curve (going down & then going up) is the Na channels opening and closing, and the second half is K channels opening (slow increase)
• it overcame the struggle of not ebing able to record both potential and permeability

Question 13

*What are the main categories of ion transporters and how do they transport ions?

Answer 13

• ATPase pumps - binding of ATP to transporter pushes 3 Na out/2 K in & later phosph’ does the reverse
• Ion exchangers (antiporters, and cotransporter) - uses the energy to move an ion down the gradient to move one against it OR uses the same energy to move one out & to move in the same direction