Body Fluid Compartments and Transport

what is total body water

total water in the body

50-70% (60%)

t/f the amount of water inversely related to fat

true

what percent of BW is intracellular fluid

40%

what percent of BW is extracellular fluid

20%

what percent of BW is plasma

4%

what percent of BW is interstitial fluid

16%

average blood volume

70mL/kg of body weight

equivalent

amount of charged solute

t/f #moles of solute is multiplied by its valence

true

osmole

#of particles into which a solute dissociates in solution

does osmole contribute to osmotic pressure

yes

t/f pH does not express H ion concentration

false, it does

interstitial fluid

tissue fluid bathing cells

electroneutrality

body fluid compartments must have same concentration of cations as anions

major ions in ECF

cation= Na+

anion= Cl- and HCO3-

major ions in ICF

cation= K+

anion= proteins & organic phosphates

ionized Ca2+

free calcium-> biologically active

total Ca2+

ionized and bound, not free to interact ??

t/f ICF has high ionized Ca2+ and is more basic

FALSE

ICF has low ionized Ca2+ and is more acididc

what is the normal mOsm concentration

300 mOsm

t/f cell membranes are not freely soluble to all solutes

true

they are selectively permeable

Na/K ATPase pump

directly uses ATP

pump Na+ out (high outside) and K+ in (high inside)

Ca2+/ ATPase pump

pump Ca2+ out of cell

directly uses ATP

transporters for glucose, AA, etc use what gradient?

Na+ gradient

do not directly use energy

resting membrane potential is due to

K+ difference

upstroke of AP and absorption of nutrients due to

Na+ difference

excitation-contraction coupling depends on

Ca2+ difference

soluble substances

do not need a transporter

ex: CO2, O2, F, steroid

water soluble

cannot diffuse across a membrane, needs a transporter

what is a cell membrane composed of

lipids and proteins

phospholipid component of cell membrane includes

glycerol backbone (water soluble) + FA tails (lipid soluble)

----> makes amphipathic

forms lipid bilayer

integral proteins

transmembrane proteins

ex: pores, ion channels,

peripheral protein

not bound to membrane, loosely attached by electrostatic interactions

**not transmembrane!!

What types of transport occur down a electrochemical gradient and do not require energy

simple or facilitated diffusion

what transport occurs against electrochemical gradient

primary transport (direct energy input)

secondary transport (indirect energy input)

is secondary transport established using primary transport

yes, so depends on Na+ gradient

t/f simple diffusion is carrier medicated

false!!! not carrier medicated

concentration gradient

driving force

larger [ ] difference

= greater driving force

partition coefficient

based on lipid solubility of solute

greater lipid solubility of solute

= easier it can diffuse

diffusion coefficient

based on size of solute and viscosity of solution

t/f very small solutes moving through non-viscous solution diffuses easily

true

thicker the membrane

harder it is to move across the

t/f greater surface area= lower diffusion rate

false, higher diffusion rate

What is one consequence of charge on an ion?

Altering the rate of diffusion of a charged solute

difference in [ ] due to charge creates voltage difference

How can a diffusion potential be created?

When a charged solute diffuses down its concentration gradient

areas of high to low [ ]

t/f facilitated diffusion uses a carrier protein, no input of energy

true

does facilitated diffusion proceed faster at low or high solute?

low

does facilitated diffusion level off @ saturation

yes, binding sites all bound

t/f simple diffusion does not keep going if there is a concentration gradient

false, it does keep going

saturation occurs because

proteins have limited number of binding sites for solute

rate of transport increases at a higher rate at

lower solute concentrations

stereospecificity

specific binding sites for solute on carrier proteins

transporters for one (D-glucose) won't transport other (L-glucose)

competition

carriers may recognize and bind chemically-related solutes

ex: D glucose similar to D galactose

primary active transport

one+ solutes moved against concentration gradient directly using ATP

t/f Na+/K+ ATPase pump is present in membranes of ALL CELLS

true

how many Na+ and K+ are pumped and in what directions

3 Na+ to ECF (out)

2 K+ to ICF (in)

**creates charge separation and potential difference

what inhibits Na/K ATPase

cardiac glycosides

what is exchanged in Ca2+ ATPase

1 Ca2+ out every ATP used for PM

for SR and ER= 2 Ca2+ from ICF into ER/SR for every ATP

H+/K+ ATPase pumps

H+ into lumen of the stomach

secondary active transport

indirecty use energy by using NA+ gradient to transport solutes against [ ] gradient

cotransport

symport same direction!!

counter-transport

antiport solutes move in opposite directions!!

Na+ moves in, other solute moves out