2 - Osmosis, Tonicity, and Pressures

osmosis

_____ is the flow of water across a semipermeable membrane due to differences in solute concentration (membrane blocks movement of solute)

osmotic pressure

Concentration difference of solutes causes difference in _____, which will cause osmosis

false

Osmosis is diffusion of water. True or false?

pressure

Osmosis occurs because of a difference in _____

greater

If one side has more solute, it has [lower/greater] osmotic pressure

pulling

Osmotic pressure is a [pushing/pulling] pressure

pushing

Hydrostatic pressure is a [pushing/pulling] pressure

hydrostatic pressure

_____ is pressure exerted by a stationary fluid at equilibrium - causes water/fluid to move or be pushed

allow fluid exchange across capillaries

Why are osmotic and hydrostatic pressures very important in cells and blood vessels?

leave

Due to hydrostatic pressure, water and some very small solutes [enter/leave] blood vessels

colloidal osmotic; oncotic pressure

With tissues and cells, osmotic pressure is referred to as _____ or _____

high

High osmolarity (many solute particles) exerts [high/low] osmotic pressure to pull water into a space, such as a blood vessel

true

Pressures favor filtration out of capillaries and into tissues. True or false?

urine; plasma; NaCl

Osmolar concentrations express the osmotic strength of solutions such as ___, ___, and ___

osmotically active particles; liter

Osmolarity is the concentration of _____ per _____ of solution (osm/Lor mOsm/L)

2

A 1 mmol/L NaCl solution would

have an osmolarity of _____ mOsm/L

osmolarity

[Osmolarity/osmolality] is the concentration of osmotically active particles per liter of solution (osm/Lor mOsm/L

osmolality

[Osmolarity/osmolality] is the concentration of osmotically active particles expressed as osmoles/kg of water

true

Osmolality is functionally the same as osmolarity. True or false?

isosmotic

Solutions of equal solute concentrations are known as _____

hyperosmotic

Refers to solution with higher concentration of solute

isosmotic

If a solution has the same osmolarity/equal osmotic pressures we call it _____

hyperosmotic

If a solution has higher osmolarity compared to another solution we call it _____

hypo-osmotic

Refers to solution with lower concentration of solute

hypo-osmotic

If a solution has a lower osmolarity compared to another solution we call it _____

less

A hypo-osmotic solution exerts [more/less] pressure

reviewed

Review

tissue tone

A measure of the effective osmotic pressure

tonicity

_____ is defined by the response of cells or tissues immersed in the solution

isotonic

A solution is _____ to cells/tissues if cells/tissues neither swell nor shrink when immersed in solution

hypotonic

A solution is _____ to cells/tissues if cells/tissues swell when immersed in solution

hypertonic

A solution is _____ to cells/tissues if cells/tissues shrink when immersed in solution

isotonic

No osmotic pressure difference between cell interior and extracellular solution

hypotonic

More solutes inside cell (higher osmolarity) relative to extracellular environment, greater osmotic pressure inside cell

hypertonic

Less solutes inside cell (lower osmolarity) relative to extracellular environment, greater osmotic pressure outside cell

reviewed

Review

oncotic pressure

Form of osmotic pressure specifically exerted by proteins, mostly albumin, within blood vessels

proteins

Oncotic pressure is specifically exerted by _____, mostly albumin, within blood vessels

into

Oncotic pressure tends to pull water [into/out of] blood vessels

interstitial colloidal osmotic

Oncotic pressure opposes _____ pressure (tissue proteins that want to pull water out of vessels)

blood oncotic pressure

Edema is a decrease in _____

hypotonic

A solution is _____ to cells/tissues if cells/tissues swell when immersed in solution

isotonic

Solutions of equal solute concentrations

osmotic pressure

Why does water move, in relation to osmosis?

solvent; solute

The semipermeable membrane is permeable to _____, but not to _______

solute - no

water - yes

Can solute move across a semipermeable membrane? What about solvent, like water?

greater; osmosis

Lot of solute = [greater/lesser] osmotic pressure -> _____

no

If there was equal amount of solute on each side, would water move?

pull

More solute on one side = greater osmotic pressure = [push/pull] water to that side of the membrane

pushing

Hydrostatic pressure = [pushing/pulling] pressure

hydrostatic pressure

-Pressure exerted by a stationary fluid

-"More fluid -> more pressure to move -> driving force" (think of watering hose)

more

More fluid in blood vessels = [more/less] pressure

hydrostatic pressure

Substances move out of capillaries and into tissues due to _____

true

Osmotic and hydrostatic pressure play a role in cells and blood vessels at the same time. True or false?

hydrostatic pressure

Generally, _____ is the dominant pressure between blood vessels and tissues

in; out

Osmotic pressure = [in/out] of blood vessels

Hydrostatic pressure = [in/out] of blood vessels

fluids; solutes

Hydrostatic pressure is due to _____, while osmotic pressure is due to _____

interstitial hydrostatic pressure

Pressure exerted by fluids between cells and tissues

blood hydrostatic pressure

Pressure exerted by fluid within the blood vessels (usually high b/c most cominant)

decreases; decrease

With dehydration, blood volume [increases/decreases]. Does the blood hydrostatic pressure increase or decrease?

osmotic

Hydrostatic pressure opposes _____ pressure

osmotic; hydrostatic

_____ pressure tends to pull water, while _____ pressure tends to push

high

Many solute particles (high conc.) = [high/low] osmolarity

increase

Concentration of solute increases in the blood vessel & more water begins to be pulled in. What will happen to blood pressure?

edema

If a lot of fluid leaves the blood vessel and enters tissues, what happens?

hydrostatic

_____ pressure is dominant

out

Pressures favor filtration [in/out] of capillaries into tissues in a normal, healthy, situation

1

1kg of water (osmolality) = ~ _____ L (osmolarity)

isosmotic

Equal solute concentrations -> same osmolarity -> same osmotic pressure

nothing

What happens to a normal cell placed in an isosmotic solution?

hyperosmotic

Solution with higher concentration of solutes -> higher osmolarity -> higher osmotic pressure

water moves from cell to solution -> cell shrivels up

What happens to a normal cell placed in a hyperosmotic solution?

water moves into cell from solution -> cell explodes/lyses

What happens to a normal cell placed in a hypoosmotic solution?

osmotic

Tonicity is a measure of the effective _____ pressure

isosmotic

Isotonic = _____

hypo

Cell/ tissues swell = solution is _____tonic to cell/tissue

hyper

Cell/tissues shrink = solution is _____tonic to cell/tissue

proteins

Oncotic pressure is pressure specifically exerted by _____ within blood vessels

albumin

Most of the protein within blood is _____

higher

We have a much [higher/lower] blood oncotic pressure because of the proteins, compared to within the tissue space

edema

Decrease in oncotic pressure is associated with tissue _____