Cell of ions

Question 1

Diff between solvent and solute

Answer 1

Solute are particles dissolved in solvent. Solvent is the fluid present.

Question 2

What are the 4 fluid compartments of the body?

Answer 2

Plasma (NA+ Based)
Interstitial (-Plasma, lacks blood proteins(anions))
Intracellular (K+ based and lots of anions)
Transcellular (In lumen of tubes/organs e.g. spinal fluid, chyme in GI)

Question 3

Difference of diffusion and osmosis

Answer 3

Diffusion the movement of solute molecules down conc gradient
Movement of solute down conc gradient

Question 4

5 important e.g. of cations and anions

Answer 4

Cation: Na,K,H,Mg2+ Ca2+
Anion: OH, Cl, HCO3, SO4, PO4

Question 5

Where are ions found? give 6 examples

Answer 5

Eggs cuffed in jail together buffering their teeth

Free in solution, tightly bound, sequestered, chelated, buffered, teeth/bones

Question 6

5 ways ions cross the membrane

Answer 6

channels, co-transporters, exchangers, pumps, leaks.

Question 7

9 things ions do

Answer 7

Start cellular process
Act as chemical messengers
Fertilisation
Muscular contraction
Exocytosis
Control transmembrane voltage 
Move water via the kidneys
Activate enzymes
Create energy as ATP

Question 8

5 things that happen if ion conc is wrong

Answer 8

Heart, face, brain, bones, skin
Cardiac arrhythmias
Tics/nervous dysfunction
Seizures
Bone deformities
Oedema

Question 9

9 things that cause ionic imbalance

Answer 9

Trauma/hemorrhage
Diabetes
Diruectics
Kidney dysfunction
hormonal imbalance
Dehydration
vitamin d imbalances
Poisons
D&V

Question 10

Conductance equation?

Answer 10

I = g x V or
g = I/V

Question 11

What is the membrane potential (Vm) and the membrane potential (RMP)

Answer 11

Vm= voltage across the membrane, this indicates real voltage and change during an AP
RMP= An ideal set point

Question 12

What is the difference betweeen chemical and electrical force

Answer 12

Chemical force is based on conc diff across a membrane e.g. 10x Na out then in then 60mv directed into cell
Electrical = based on the Vm and having unpaired +ve charge with -ve charge on one side of the membrane

Question 13

What is equilibrium of chemical and electrical force?

What is the equation of net force?

Answer 13

Chemical force = -1x electrical force:
net force = 0

Net force = chemical + electrical force

Question 14

Is Potassium and Sodium higher intracellular or extracellular?

Answer 14

Potassium higher inside

Sodium higher outside

Question 15

What is the diff between excitable and non-excitable tissues? give examples.

Answer 15

Excitable: able to propegate an AP e.g. muscle and neurons

Non-excitable: cells w/o an AP e.g. epithelial, skin, liver

Question 16

Describe the differences between body fluids composition of Plasma, Intracellular fluid and extracellular space.

Answer 16

plasma: Highest in Na to balance protein anions, slightly negative than ECF
ICF: Highest cations, highest proteins, higher elctrolyte conc, most negative voltage
Extracellular space:
Highest Cl conc(lacks protein anions)
lowest elctrolyte conc

Question 17

Describe the 4 places where calcium can be found

Answer 17

Free Calcium, ionized and in solution (free to activate enzymes)
Bones, insoluble solid will not react w enzymes
Bound to proteins will not react
Sequestered in cellular organelles e.g. sarcoplasmic reticulum

Question 18

What does free Ca do? and explain the differnece between inside and outside the cell

Answer 18

Free Ca is 10,000x more outside the cell than inside.

Enzymes and proteins are activated when IC free Ca is increased causing changes such as muscle contraction

Question 19

What are the 3 rules of ionic balance

Answer 19

1. Conc of +/- ions must nearly balance
2. Ions leave cell must be replaced by the same ion
3. Energy is used to re-establish ion gradients across membranes

Question 20

Carbonic anhydrase is used to

Answer 20

Create acid/base
Indirectly helps H+ cross membranes
Indirectly helps CO2 transport around the body
Cl shift to remove H+ from muscle in RBC
Eliminating CO2 in lungs
Secreting HCl in gastric parietal cells into the stomach
Secreting bicarbonate in the pancreas

Question 21

What it the carbonic anhydrase catalyst reaction?

Answer 21

CO2+ H2O -> H2CO3 -> H+ + HCO3-

Question 22

Name the process of the gastric parietal cells moving ions in 4 steps.

Answer 22

1. Pumps H/K against conc gradient creates acidic space outside. Bicarb inside the cell out to blood and diluted to co2 then breathed out.
2. K channels open and k moves via conc gradient out cell. Cl- moves out with H to pump out HCl. Cl moves down conc gradient.
3. Cl- channels open and cl moves passively to get rid of extra cl. K channels balance charge.
4. NaK pump maintains intracellular K conc.