Module 6 - Osmolarity

Question 1

Osmolarity

Answer 1

the number of particles of solute per liter of solution; it is expressed as mOsm/L

Question 2

Normal osmolarity is

Answer 2

270-300 mOsm/L

Question 2

Osmolarity is derived from

Answer 2

the measure of Na+, K+, urea and glucose concentrations in the blood or urine

Question 3

Concentration is expressed in… (3)

Answer 3

milliequivalents per liter (mEq/L), millimoles per liter (mmol/L), and milliosmoles per liter (mOsm/L)

Question 4

Solvent

Answer 4

water

Question 5

Solutes in the body

Answer 5

Solutes are particles in fluid circulation that have an electrical charge (electrolytes)

Question 6

Cations

Answer 6

positively charged ions that act as solutes

Question 7

Anions

Answer 7

negatively charged ions that act as solutes

Question 8

Flitration

Answer 8

Filtration is the passage of a fluid such as water, through a cell or blood vessel membrane

Question 9

What causes fluid to move on the capillary level

Answer 9

interstitial compartment capillary hydrostatic pressure and interstitial fluid osmotic pressure

Question 10

Diffusion

Answer 10

Diffusion is the passive movement of solute across a permeable membrane from an area of higher particle concentration to an area of lower particle concentration

Question 11

How does diffusion occur?

Answer 11

particles bump into each other and the cell membrane and when the cell membrane is struck enough times a pore big enough to let the particles through opens allowing diffusion
-the more particles the faster this happens

Question 12

what do plasma proteins such as albumin and globulin do for fluid movement?

Answer 12

they contribute to osmotic pressure
Globulin particles specifically hold water in the blood and pull it into the blood from tissues or cells.
Albumin particles specifically encourage fluid return and prevent fluid loss into transcellular spaces of the peritoneal and pleural cavities

Question 13

Hypertonic

Answer 13

fluids with osmolarities greater than 300 mOsm/L are hyperosmotic, or hypertonic, compared with isosmotic fluids

Question 14

Hypotonic

Answer 14

fluids with osmolarities of less than 270 mOsm/L are hypo-osmotic, or hypotonic, compared with isosmotic fluids

Question 15

Causes of Edema

Answer 15

-Increased capillary hydrostatic pressure (higher blood pressure): The high pressure in the capillary pushes fluid out into the tissues and prevents it from returning to circulation.
-Decreased plasma osmotic pressure: The loss of proteins (albumin) in the blood allows for fluid to leave the plasma and go into the tissues.
-Obstruction of the lymphatic circulation: Usually causes a localized edema since excessive fluid and protein are not returned to the general circulation.
-Increased capillary permeability: When damaged, capillaries allow solutes such as protein to leak out. This usually causes localized edema and may result from an inflammatory response (burn) or infection (sepsis)

Question 16

Osmotic pressure

Answer 16

pulls water into the capillary vessels from the interstitial space

Question 17

Hydrostatic pressure

Answer 17

pushed water out of the capillaries and into interstitial space