Osmolarity, Membranes, Membrane Transport

What is one word to sum up the definition of Anatomy?

structure

What is one word to sum up the definition of Physiology?

function

Pathophysiology is the science of...

disordered physiological processes associated with disease or injury

At the molecular level of organization, what controls gene expression?

transcription factors

At what level of organization does transcription, translation and genetic programming occur?

molecular

At what level of organization does protein production occur?

molecular

At what level of organization will organelles, transduction, metabolism, and transport be involved?

cellular

What is a tissue?

aggregation of single type of specialized cell

Name the 4 kinds of tissues.

muscle, nerve, epithelial, connective

What is an organ composed of?

4 kinds of tissue

Organ systems utilize a group of ? that operate in a ? fashion to achieve a ? function.

cells, coordinated, specialized

At what level of organization does regulation & integration occur?

organ systems

At what level of organization are complex regulatory mechanisms introduced?

organism

Which chemical messenger circulates in the blood and acts on another cell?

hormone

Which chemical messenger acts only on close by target cells?

paracrine

Which chemical messenger acts on the same cell it was secreted by?

autocrine

What accounts for 79% of body composition?

lean body mass

What accounts for the other 21% of body composition?

adipose tissue

What are the two types of storage fat?

subcutaneous and visceral

How much water is typically found in the body (% and L)?

57%, 40 L

Where is most of the water (25 L) in the body found?

ICF

Which fluid volume accounts for water found in all cells including red blood cells?

ICF

How much water can be found in the ECF?

15 L

Which fluid volume accounts for water found in the interstitial and plasma fluid spaces?

ECF

Which contains more water, intracellular or extracellular compartments?

intracellular

Which contains more water, interstitial fluid or the plasma?

interstitial

Why are infants more susceptible to dehydration?

higher water content (65-70%)

What are the 2 minor body fluid compartments?

transcellular, restricted

What are the 4 transcellular compartments?

gut, urinary bladder, gall bladder, lymph

What are the 2 restricted compartments?

cerebrospinal fluid, intraocular fluid

What are the 3 components of and indicator dye?

dispersion only in compartment, even dispersion, not metabolized/excreted

What is D2O used as an indicator for?

total body water

How is intracellular fluid determined (equation)?

total body water - ECF volume

What are Na (22) and inulin used as indicators for?

ECF volume

What is I-Albumin used as an indicator for (compartmentally)?

plasma volume

Where is I-albumin typically confined to?

vascular space

What disease can high I-albumin levels from urine identify?

kidney disease

How can interstitial fluid volume be measured (equation)?

ECF volume - plasma volume

What is the equation for BMI?

BMI = kg/m2

What does a BMI between 18.5 to 24.9 indicate?

normal weight

What does a BMI below 18.5 indicate?

underweight

What does a BMI of 30 or greater indicate?

obesity

How many mEq of Ca++ and Cl- are in 1 mM CaCl2?

2 mEq Ca++/L and 2 mEq Cl-/L

1 mole/L = ?

1 molar or 1M

1 mole/kg = ?

1 molal

How many osmotically active particles are present in the fluid of plasma?

280-300 mOsm/L of water

Osmolarity measures the amount of osmotically active particles per ?

L of solvent

Osmolality measures the amount of osmotically active particles per ?

kg of water

What is the key characteristic about osmotically active particles?

can not cross cell membrane, require transporter

How would osmolarity change if you were to put a large amount of salt into a L water?

increase

How does an increase in the amount of solute impact the concentration of water?

decrease

The ? and ? of osmotically active particles does NOT matter.

size, type

How does water move by osmosis?

down it's concentration gradient

Movement of water by the concentration gradient flows from ? concentration of solute to ? concentration of solute.

lower to higher

When does water movement stop?

equilibrium reached, equal osmolarities

Which 2 sub-compartments of ECF is Na+ concentration highest in?

plasma, interstitial

Which 2 ions have high concentrations in ECF?

Na+, Cl-

Where is the concentration of K+ very high?

ICF

What is the concentration of K+ in ICF(mEq/L)?

120-145

What is the concentration of Na+ in both compartments of ECF(mEq/L)?

130-145

Why is protein concentration 0 in interstitial fluid but has some presence in plasma?

cant cross capillary wall

What is the major anion present in ICF?

protein

What health condition is assosciated with increased protein in interstitial fluid?

edema

What molecule present on the cell membrane (IC side) works to keep the balance between Na+ out and K+ in?

ATP

When Osmolarity of ECF < ICF how does net movement occur?

water moves from ECF to ICF

When Osmolarity of ECF > ICF how does net movement occur?

water moves from ICF to ECF

Water flows evenly (but no net movement) when...

ECF = ICF

How does a 10 L increase in water affect the osmolarity of ALL 3 compartments (TBW, ECV, ICV)?

decrease

Why does a 10 L increase in water increase the volume for both ECV and ICV?

no osmotically active particles = water goes everywhere

What are both fluid and electrolyte output regulated by?

kidneys

What must be regulated to maintain blood pressure?

ECF volume

What is of primary importance for regulation of ECF volume?

salt balance

What must be regulated to prevent swelling/shrinking of cells?

ECF osmolarity

What is of primary importance for regulation of ECF osmolarity?

water balance

What are the 3 major chemical components of membranes?

lipids, proteins, carbs

What is the framework for all membranes?

lipids

What accounts for the largest component of cell membranes?

proteins

What component is responsible for membrane FUNCTION?

proteins

In which membrane are 70% of proteins present?

inner mitochondrial membrane

What portion of proteins are present in myelin sheath (%)?

20%

What % of plasma membrane weight do carbohydrates account for?

2-10%

What type of fatty acids allow for greater fluidity of the plasma membrane (2)?

unsaturated, shorter

How does a shorter fatty acid tail contribute to greater fluidity?

less likely to form hydrophobic interactions

What 2 types of interactions hold together the lipid bilayer?

hydrophobic bonds, Van der Waals forces

What is the most abundant membrane lipid?

glycerophospholipids

What is the second most abundant membrane lipid?

sphingolipids

What is the third most abundant membrane lipid?

cholesterol

What membrane lipid is only present in animals?

cholesterol

What are 2 key physical characteristics of cholesterol?

rigid, hydrophobic

What are the 2 key functions of cholesterol in the plasma membrane?

determine membrane fluidity, prevent crystallization

? % of drugs exert their effect by binding to membrane ?.

70%, protein

What are the 3 different types of membrane proteins?

integral, peripheral, lipid-anchored

What transmembrane protein do a majority of drugs target and bind to?

G-protein coupled receptors (GPCR)

What is one type (subclass) of integral protein?

transmembrane protein

What interactions attach a peripheral protein to the plasma membrane?

weak electrostatic interactions with phospholipid heads / to integral protein

How are lipid-anchored proteins attached to the plasma membrane?

covelently attached to FA acyl chain/ to peripheral proteins

What 2 types of carbohydrates are present in plasma membranes?

glycoprotein, glycolipid

Which way does the carbohydrate (R-COOH) face?

away from cytosol

What are the 4 functions of carbohydrates in the plasma membrane?

protection, recognition, cell adhesion, defense

What are the 2 things that membrane fluidity depends on?

lipid composition/concentration, temperature