NU545 CHAPTER 3 EXAM QUESTIONS AND
ANSWERS WITH COMPLETE SOLUTIONS LATEST
UPDATE
Total Body Water (TBW): Definition
The sum of fluids within all compartments constitutes the TBW
What are the 5 types of fluid that make up the TBW?
1. Intracellular fluid
2. Extracellular fluid
3. Interstitial fluid
4. Intravascular fluid
5. Transcellular fluids
Intracellular fluid (ICF): Definition
Inside the cell, 2/3 of body water
Extracellular fluid (ECF): Definition
Outside the cell, 1/3 of body water
Extracellular fluid (ECF) includes:
- Interstitial fluid (4/5 of ECF)
- Intravascular fluid (1/5 of ECF)
,- Cerebrospinal fluid (CSF)
- Lymphatic, synovial, intestinal, biliary, hepatic, pancreatic, pleural, peritoneal, pericardial, and
intraocular fluids
- Sweat
- Urine
Interstitial fluid: Definition
The fluid surrounding the cells and found in the spaces between cells but not within the blood vessels
Intravascular fluid: Definition
fluid within blood vessels (aka blood plasma)
Transcellular fluid: Definition
The fluids contained within epithelial-lined cavities of the body: including pleural, synovial, peritoneal,
pericardial, and intra-ocular fluids
Osmolality: Definition
# of osmotically active particles per kg of water
think CONCENTRATION of a solution
How does water move between ICF and ECF compartments?
Osmotic forces
- Sodium for the ECF
- Potassium for the ICF
What are aquaporins?
, A family of water channel proteins that provide permeability to water. Water moves freely by diffusion
through the lipid bilayer cell membrane and through aquaporins
Definition of osmosis
How water moves between the ICF and ECF compartments
What happens when ECF osmolality changes?
water moves from one compartment to another until osmotic equilibrium is reestablished. Water
crosses cell membranes freely so the osmolality of TBW is normally at equilibrium
Water Movement between Plasma and Interstitial Fluid: Starling hypothesis (aka Starling forces)
Net filtration is equal to the forces favoring filtration minus the forces opposing filtration
Forces favoring filtration
- Capillary hydrostatic pressure (blood pressure)
- Interstitial oncotic pressure (water pulling)
Forces opposing filtration
- Capillary (plasma) oncotic pressure (water pulling)
- Interstitial hydrostatic pressure
Alterations in Water Movement: Edema - Definition
Accumulation of fluid in the interstitial spaces. Results from a shift of fluid from the capillaries
(Intravascular fluid) or lymphatic vessels into the tissues
Edema - Causes
ANSWERS WITH COMPLETE SOLUTIONS LATEST
UPDATE
Total Body Water (TBW): Definition
The sum of fluids within all compartments constitutes the TBW
What are the 5 types of fluid that make up the TBW?
1. Intracellular fluid
2. Extracellular fluid
3. Interstitial fluid
4. Intravascular fluid
5. Transcellular fluids
Intracellular fluid (ICF): Definition
Inside the cell, 2/3 of body water
Extracellular fluid (ECF): Definition
Outside the cell, 1/3 of body water
Extracellular fluid (ECF) includes:
- Interstitial fluid (4/5 of ECF)
- Intravascular fluid (1/5 of ECF)
,- Cerebrospinal fluid (CSF)
- Lymphatic, synovial, intestinal, biliary, hepatic, pancreatic, pleural, peritoneal, pericardial, and
intraocular fluids
- Sweat
- Urine
Interstitial fluid: Definition
The fluid surrounding the cells and found in the spaces between cells but not within the blood vessels
Intravascular fluid: Definition
fluid within blood vessels (aka blood plasma)
Transcellular fluid: Definition
The fluids contained within epithelial-lined cavities of the body: including pleural, synovial, peritoneal,
pericardial, and intra-ocular fluids
Osmolality: Definition
# of osmotically active particles per kg of water
think CONCENTRATION of a solution
How does water move between ICF and ECF compartments?
Osmotic forces
- Sodium for the ECF
- Potassium for the ICF
What are aquaporins?
, A family of water channel proteins that provide permeability to water. Water moves freely by diffusion
through the lipid bilayer cell membrane and through aquaporins
Definition of osmosis
How water moves between the ICF and ECF compartments
What happens when ECF osmolality changes?
water moves from one compartment to another until osmotic equilibrium is reestablished. Water
crosses cell membranes freely so the osmolality of TBW is normally at equilibrium
Water Movement between Plasma and Interstitial Fluid: Starling hypothesis (aka Starling forces)
Net filtration is equal to the forces favoring filtration minus the forces opposing filtration
Forces favoring filtration
- Capillary hydrostatic pressure (blood pressure)
- Interstitial oncotic pressure (water pulling)
Forces opposing filtration
- Capillary (plasma) oncotic pressure (water pulling)
- Interstitial hydrostatic pressure
Alterations in Water Movement: Edema - Definition
Accumulation of fluid in the interstitial spaces. Results from a shift of fluid from the capillaries
(Intravascular fluid) or lymphatic vessels into the tissues
Edema - Causes
