Human Phys 1.2 Flashcards
What is the percentage of total body water?
50-70% of body weight
What is total body water inversely proportional to?
Body fat
How much total body water is in intracellular fluid?
2/3 (40%)
How much total body water is in extracellular fluid?
1/3 (20%)
What are the two components that make up extracellular fluid?
Interstitial fluid and plasma
What is interstitial fluid to plasma?
An ultra filtrate
Where is interstitial fluid located?
Outside of blood vessels between cells
Where is plasma located?
Inside blood vessels
Why will the concentration be equal between interstitial fluid and plasma?
Because Na+ K+ can move freely between the two
What cannot leave plasma?
Some plasma proteins
If you remove cells and platelets from blood what do you have?
Plasma
If you remove clotting proteins from plasma what do you have?
Serum
Permeability
How easily something can pass through a cell membrane
What is the permeability of ions?
Low (can only pass with a channel)
What is the permeability of large uncharged polar molecules?
Low (very hard to cross cell membrane)
What is the permeability of small uncharged polar molecules?
Higher (but generally still don’t cross cell membrane often)
What is the permeability of hydrophobic molecules?
Highest (easily cross cell membrane)
Downhill transport
Substances move down a concentration gradient from an area of high concentration to low concentration
What does downhill transport occur by?
Passive transport
What are the types of passive transport?
Simple diffusion
Facilitated diffusion
Does downhill transport require energy?
No
Uphill transport
Substance move against a concentration gradient from an area of low concentration to high
What does uphill transport occur by?
Active transport
What are the types of active transport?
Primary active transport
Secondary active transport
Does uphill transport require energy?
Yes
What are the two main classes of membrane transport proteins?
Channels
Transporters
Channels
Always passive, but much faster
Transporters
Can be passive or active
What does a channel protein behave like?
Doorway (same properties as simple diffusion)
What types need a protein carrier?
Facilitated diffusion
Primary active transport
Secondary active transport
What types do not need a protein carrier?
Simple diffusion
