Physiology Objectives #3 - Fluid Transport

Front 1

How blood moves across a membrane and the fluid compartments it maintains

Back 1

It moves down its [concentration] and maintains blood, interstitial and intracellular volumes

Front 2

Role of aquaporins

Back 2

act as water channels in plasma membrane, increasing its net flux

Front 3

Forces driving water movement across membranes (2)

Back 3

osmotic and hydrostatic pressure

Front 4

This determines Osmotic Pressure

Back 4

overall free [solute] within a fluid

Front 5

These determine hydrostatic for

Back 5

The effect of gravity on a fluid along with hydraulic pressure if the fluid is moving

Front 6

Assuming hydrostatic pressure is negligible, this is how Net flux, Jx, is calculated

Back 6

Jwater = Lp [RT (Osmi - Osmo)] where Lp = membrane permeability to water and Osm = [osmotically activesolutes]

Front 7

Equation for osmotic pressure

Back 7

ΔOsm = σΔCγRT

Front 8

Difference btwn Osmolarity and Osmolality

Back 8

osmol/L and Osmol of solute/ kg of water

Front 9

Tonicity:
• What it describes and what it affects
• what it depends on
• Main rule to determine tonicity

Back 9

Tonicity:
• Describes a solution and how that solution affects cell volume
• It depends on whether the solutes in the solution are penetrating/non-penetrating
• Compare the osmolarity of non-penetrating particles

Front 10

All hypo-osmotic solutions can be described as this

Back 10

hypotonic

Front 11

How to determine the tonicity of a hyperosmotic solution

Back 11

compare the relative [non-penetrating solutes] in the cell and solution

Front 12

The effect of a 0.9% saline solution on an intracellular environment

Back 12

Both the ICF and ECF contain 290 mOsm of non-penetrating solute. This is a iso-osmotic and isotoic environment --> No net movement of water across the cell membrane Condition used: to increase blood volume/pressure due to blood loss

Front 13

The effect of a 5% dextrose in normal saline solution on an intracellular environment

Back 13

The ICF has 290 mOsm while the ECF has 580 mOsm, thus the solution is hyper-osmotic.

Both the ICF and ECF have 290 mOsm of non-penetrating solute (NaCl) while the ECF has 290 mOsm of pentrating solute (dextrose).

Tonicity says we only pay attention to the [non-penetrating particles] so the solution is isotonic --> No net movement of water across the cell membrane Condition used: to increase blood volume/pressure due to blood loss

Front 14

The effect of a 5% dextrose in water on an intracellular environment

Back 14

Though they have different particles, both the ICF and ECF contain 290 mOsm --> the solution is iso-osmotic.

The ECF has 290 mOsm of penetrating particles while the ICF has 290 mOsm of non-penetrating particles (NaCl).

Tonicity says we only pay attention to the [non-penetrating particles] so the solution is hypotonic --> Net movement of water into the cell Condition used: to rehydrate

Front 15

The effect of a half normal saline solution on an intracellular environment

Back 15

The ICF has 290 mOsm while the ECF has 145 mOsm, thus the solution is hypo-osmotic.

The ICF and ECF contain the same species non-penetrating particles (NaCl) but the ECF contains half as much.

The solution is hypotonic --> There is net movement of water into the cell Condition used: rehydrate

Front 16

The effect of a 5% dextrose in half normal saline on an intracellular environment

Back 16

The ICF has 290 mOsm while the ECF has 435 mOsm, thus the solution is hyper-osmotic.

The ICF and ECF contain the same species of non-penetrating particles (NaCl) but the ECF contains half as much.

The solution is hypotonic --> There is net movement of water into the cell Condition used: rehydrate

Front 17

Differentiate btwn transcellular and paracellular movement

Back 17

Transcellular - movement across epithelial cells Paracellular - mvment btwn epithelial cells