Lecture 2 Body Fluids and Membrane Transport Flashcards
State the composition of the human body for a 30 year old 70kg male
18 percent fat
22 percent lean body mass
60 percent water
What percentage of your body composition is water
60 percent is water, approx 42 litres.
How many litres constitute the Total body water
42 litres. This is equal to 60 percent of the total body composition.
What is the total body water comprised of, and how many litres make up each part.
25 litres is Intracellular fluid
17 liters is extracellular fluid.
What is the Extracellular fluid made up of.
13 litres is Interstitial fluid
3 liters is plasma
1 liter is transcellular fluid.
How many liters of interstitial fluid do we have
13
How many liters of plasma do we have
3
Give examples of some transcellular fluids
- Cerebrospinal fluid
- Urine
- GI secretions inc. saliva, gastric juice, pancreatic juice, bile and sweat.
- aqueous and vitreious humours.
- synovial fluid.
Interstitial fluid is how many liters
13 liters is interstitial fluid
Plasma is how many liters
3 liters is plasma
Transceullar fluid is how many liters
1 liter of transceullular fluid
Describe the ion concentrations of the Blood Plasmsa
Na+= 142mM
K+ = 4.4mM
Cl- = 102mM
Protein =1mM
Low K+
High Na+
High Cl-
1mM protein.
(high/low compared with Intracellular fluid)
What is the osmolality of the Blood plasma
290 mOsm
Describe the relative protein concentrations in the E.C.Fs (the blood plasma, and interstitial fluids, transcellular fluid) compared with the I.C.F intracellular fluids
Blood has 1mM protein
Interstitial fluid has no protein
Intracellular fluid has 4mM protein
Transcellular fluid has variable protein concentration
Which fluid has the most protein
The intracellular fluid has 4mM protein.
Describe the ion concentrations of the Intracellular fluid
High K+
Low Na+
Low cl-
High protein [4mM]
Intracellular fluid has less sodium E.C.F but more potassium than the extracellular fluids.
Where is the concentration of potassium ions highest
In the intracellular fluid.
Give the osmolality of the Extracellular fluid
290 mM
Give the osmolality of the intracellular fluid
290mOsm
What are the ion concentrations of the transcellular fluid. And what is the osmolality of transcellular fluid
Variable. and Variable omsolality.
State three key features of the Plasma membrane
- Highly selective permeability
- lots of transport proteins for uptake and removal of specific solutes
- vital for regulation for the intracellular environment
Describe the permeability of the membrane
Phospholipid bilayer is impermeable to ions and polar molecules.
Describe the three categories of transporter proteins
- Channel protein
- Carrier protein
- Pump
Which ion transporter proteins are passive
Channel mediated and carrier mediated
Which transporter requires energy
Pumps require energy from ATP hydrolysis to pump the ions against the concentration gradient.
Name the three types of carrier protein
Facilitator (uniport)
Co-transporter (symport)
Exchanger (antiport)
What are the functions of transport proteins
Uptake of nutrients, uptake of substrates uptake of cofactors. export of waste products regulate intracellular ion content regulate ph regulate cell volume
Describe the differential distributions of water and solutes inside the plasma membrane
High potassium Low sodium very low calcium very low chlorine high protein
Describe the differntial distributions of water and solutes outside the plasma membrane/ in the EXTRA cellular fluid
Low potassium High sodium (salty bannana) low calcium (higher than inside) High chlorine Low protein
Explain how the membrane potential is established
- Due to asymmetric distribution of K+
What is meant by antiport, give an example
Refers to when 2 ions are swapped or exchanged with eachother. Exchanger = carrier protein involved
What is meant by symport, give an example
Refers to when 2 ions are moved simeltaneously from one region to another. Co-transporter is the carrier protein involved
What is meant by uniport, give an example of a transporter
Uniport is when one ion is moved at once, Facilitator is the type of carrier protein involved.
How is the membrane potential generated
Asymmetric distribution of K+ ions generates a membrane potential.
With reference to ion concentrations, explain how the membrane potential is generated
K+ is pumped across the membrane to the extracellular fluid
How does water distribute itself
Water distributes itself so that the osmotic pressures, Pi i and Pi o are equal.
Water will move down hydrostatic pressure gradients.
What is the capillary endothelium
A very thin layer of cells lining blood vessels. It is highly permeable in some organs but not in other organs.
Describe three key features of the capillary endothelium
- Very thin layer of cells lining the blood vessels.
- Highly permeable in some organs but not in others.
- Has important role in regulation of the interstitial fluid.
Describe the relative concentrations of small ions and organic solutes in the ISF compared with the blood plasma inside the capillaries.
there is a low concentration of small ions and organis solutes in the interstitial fluid, while there is a high concentration of organic solutes and small ions in the plasma.
What are the relative concentration of protein in the ISF compared with the Blood plasma
High protein in the blood plasma (inside capillary) with low protein in the ISF
Describe the distribution of solutes across the capillary endothelium
The concentations of small ions and organis solutes in the Interstitial fluid are approx. equal to those in the Blood plasma.
Protein conc. is low in ISF compared with the blood plasma.
What is the colloid osmotic pressure
Delta Pi c
State 3 important roles of Epithelia
- Epithelia are layers of cells covering internal and external surfaces of organs and tissues.
- function as a protective barrier
- have important roles in absorption and secretion.
- found in kidney tubule, lumen of the gut,
Describe Epithelial transport across the lumen of the Gut for Sodium Na+
- Sodium is pumped into the intestinal epithelial cell from the apical membrane.
- Na+ is pumped out into the basolateral membrane.
- ## K+ is pumped into the intestinal epithelial cell from the basolateral membrane.
Describe the transport of glucose across the epithelium
- Glucose is transported from the apical membrane into the intestinal epithelial cell.
- Glucose diffuses out of intestinal epithelia into baso-lateral membrane.
YOU NEED TO LOOK AT LECTURE SLIDES FOR slides 14-22.
ok i will do this.
