Approximately ___% of the body weight of an adult is water. Men? Women?
60%
Men --> 55-65%
Women --> 45-55%
Water content in the body varies with what?
gender, body mass/type, and age
Infants typically have ___-___% water in their body. Older adults?
Why does this matter?
Infants --> 70-80%
Older adults --> 45-55%
These groups are at a greater risk of fluid imbalances
Why do men have higher water content in their body than women?
Fat cells hold little water so men have more water content and women and
obese patients have less water content.
What are the two major body fluid compartments?
Intracellular --> fluid within the cells
Extracellular --> fluid outside the cells
What are the subtypes of Extracellular fluid?
Interstitial --> surrounding the cells
Intravascular --> Within the blood vessels (aka plasma - the liquid part of
blood)
,Transcellular --> Very small amount of fluid found in specialized cavities
(cerebrospinal fluid, synovial fluid, GI tract, etc)
What is the function of water in the body?
- Provides lubrication of musculoskeletal joints
- Transport mechanism throughout body for nutrients, hormones, proteins,
electrolytes
- Medium for cellular metabolism (aids in food breakdown)
- Regulation of body temp (think perspiration)
- Acts as a component in all body cavities
What is Osmosis?
- Movement of water between two compartments from area
of LOW CONCENTRATION OF SOLUTE to area
of HIGH CONCENTRATION OF SOLUTE.
* water goes to dilute the concentration
PROCESS IS PASSIVE! REQUIRES NO ENERGY!
How does osmosis work?
The solutes (solids) create osmotic pressure.
The pressure pulls water towards the solutes
Osmotic Pressure?
Amount of hydrostatic pressure needed to stop the flow of water by osmosis.
, The greater the concentration of solutes the greater the PULLING force on
water.
Oncotic Pressure? AKA?
Colloidal Osmotice Pressure
Form of osmotic pressure created by the pull of H2O towards a higher protein
(colloid) concentration
Osmotic Diuresis?
The increase in urine output caused by the excretion of substances, such as
glucose.
*This diuresis means to create more urine
Tonicity?
The ability of all solutes to cause an osmotic driving force that promotes water
movement from one compartment to another.
Ex. Protein draws water towards it just like salt does
Osmolality?
Number of milliosmoles (the standard unit of osmotic pressure) per kilogram of
solvent.
We measure the urine and serum (blood) osmolality
Diffusion?
The movement of solutes from HIGH to LOW CONCENTRATION.
- Passive = requires no energy
- Occurs in liquids, gasses, and solids
- Membrane separating the two must be permeable to the molecules that are
moving.
Example of diffusion?
60%
Men --> 55-65%
Women --> 45-55%
Water content in the body varies with what?
gender, body mass/type, and age
Infants typically have ___-___% water in their body. Older adults?
Why does this matter?
Infants --> 70-80%
Older adults --> 45-55%
These groups are at a greater risk of fluid imbalances
Why do men have higher water content in their body than women?
Fat cells hold little water so men have more water content and women and
obese patients have less water content.
What are the two major body fluid compartments?
Intracellular --> fluid within the cells
Extracellular --> fluid outside the cells
What are the subtypes of Extracellular fluid?
Interstitial --> surrounding the cells
Intravascular --> Within the blood vessels (aka plasma - the liquid part of
blood)
,Transcellular --> Very small amount of fluid found in specialized cavities
(cerebrospinal fluid, synovial fluid, GI tract, etc)
What is the function of water in the body?
- Provides lubrication of musculoskeletal joints
- Transport mechanism throughout body for nutrients, hormones, proteins,
electrolytes
- Medium for cellular metabolism (aids in food breakdown)
- Regulation of body temp (think perspiration)
- Acts as a component in all body cavities
What is Osmosis?
- Movement of water between two compartments from area
of LOW CONCENTRATION OF SOLUTE to area
of HIGH CONCENTRATION OF SOLUTE.
* water goes to dilute the concentration
PROCESS IS PASSIVE! REQUIRES NO ENERGY!
How does osmosis work?
The solutes (solids) create osmotic pressure.
The pressure pulls water towards the solutes
Osmotic Pressure?
Amount of hydrostatic pressure needed to stop the flow of water by osmosis.
, The greater the concentration of solutes the greater the PULLING force on
water.
Oncotic Pressure? AKA?
Colloidal Osmotice Pressure
Form of osmotic pressure created by the pull of H2O towards a higher protein
(colloid) concentration
Osmotic Diuresis?
The increase in urine output caused by the excretion of substances, such as
glucose.
*This diuresis means to create more urine
Tonicity?
The ability of all solutes to cause an osmotic driving force that promotes water
movement from one compartment to another.
Ex. Protein draws water towards it just like salt does
Osmolality?
Number of milliosmoles (the standard unit of osmotic pressure) per kilogram of
solvent.
We measure the urine and serum (blood) osmolality
Diffusion?
The movement of solutes from HIGH to LOW CONCENTRATION.
- Passive = requires no energy
- Occurs in liquids, gasses, and solids
- Membrane separating the two must be permeable to the molecules that are
moving.
Example of diffusion?
