from molecules to cells

Question 1

what are the most important molecules in neuron signaling?

Answer 1

water
lipids
proteins
ions

Question 2

what are lipids?

Answer 2

chains of carbon atoms (oils and fats)

Question 3

what are proteins?

Answer 3

chains of amino acids

Question 4

what are ions?

Answer 4

single atoms that have a positive or negative charge

Question 5

what is an amphiphilic molecule?

Answer 5

a molecule that has a polar (head) and a non polar (carbon chain) parts

Question 6

what does amphiphilic molecules make?

Answer 6

the cell membrane
lipid bilayer

Question 7

what do proteins do in the cell membrane?

Answer 7

transportation of molecules
an interface between inside and outside of the cell

Question 8

where are large negative molecules located?

Answer 8

anchored inside the cell

Question 9

what are the 3 most important ions in a neuron?

Answer 9

Na+
Cl-
K+

Question 10

what do the K+ ions do?

Answer 10

they go through their ion channel to counteract the large negative molecules inside the cell

Question 11

where is the concentration high of K+?

Answer 11

in the cell

Question 12

where is the concentration high of Na+?

Answer 12

outside of the cell

Question 13

what are ion pumps?

Answer 13

they move selective ions in and out of the cell
requires ATP

Question 14

what is the fluid inside the cell called?

Answer 14

cytosol

Question 15

what does the uneven distribution of ions across the membrane make?

Answer 15

it makes an electrical potential

Question 16

what is voltage?

Answer 16

the electrical potential between 2 points

Question 17

what is electrical potential called when talking about a cell?

Answer 17

it is called a membrane potential

Question 18

how does membrane potential work?

Answer 18

the more an ion moves across the membrane, the more the membrane potential is determined by that ion’s concentration difference

Question 19

what kind of voltage will K+ have when the cell is “at rest”?

Answer 19

it will have a negative voltage

Question 20

what kind of voltage will Na+ have when the cell is “at rest”?

Answer 20

it will have a positive charge

Question 21

what is the voltage when the cell is at rest?

Answer 21

V= -70

Question 22

what is the voltage when the Na+ channels start to open?

Answer 22

V= +40

Question 23

what makes an ion channel open and close?

Answer 23

the factors affecting them

Question 24

what is a ligand-gated channel?

Answer 24

an extracellular chemical attaches on to the protein, causing it to open

Question 25

what is a voltage dependent channel?

Answer 25

changes in he membrane potential, causes the channel to open/close

Question 26

what is an excitatory post synaptic potential?

Answer 26

a positive change (depolarization) caused by opening of ligand-gated ion channel at a synapse

Question 27

what is an inhibitory post synaptic potential?

Answer 27

a negative voltage change caused by the opening of a ligand-gated ion channel at a synapse

Question 28

what is action potential?

Answer 28

a rapid change in voltage caused by a positive feedback effect, involving voltage-sensitive sodium channels

Question 29

what is synaptic integration?

Answer 29

depolarization events combine to either reach threshold or not

Question 30

what is absolute refectory period?

Answer 30

sodium channels are inactivated

Question 31

what is the relative refectory period?

Answer 31

hyperpolarization by open potassium channels reduces likelihood of another action potential

Question 32

where are voltage sensitive sodium channels located in high densities?

Answer 32

the axon hillock