NR 412 – Exam 1 Practice Questions and Verified Answers – Nursing Pathophysiology and Fluid/Electrolyte Balance Review (Comprehensive Study Material)

What is the total body water (TBW) per body weight in infants?
~CORRECT ANSWER~✓✓75-80%



What is the total body water (TBW) per body weight in adult males?
~CORRECT ANSWER~✓✓60%



What is the total body water (TBW) per body weight in adult females?
~CORRECT ANSWER~✓✓50%



What is the total body water (TBW) per body weight in obese adults?
Why? ~CORRECT ANSWER~✓✓30-40% because of the increase in
adipose tissue, and decrease in muscle mass in obese people



What is the total body water (TBW) per body weight in elderly adults?
Why? ~CORRECT ANSWER~✓✓45% because they have a decrease in
muscle mass and decreased thirst mechanism in hypothalamus



List some functions of body fluids ~CORRECT ANSWER~✓✓-Maintain
blood volume

-Regulate body temperature

-Transport material to and from cells

,-Serves as an aqueous medium for cellular metabolism

-Assists with food digestion

-Serves as a medium for excreting waste



Intracellular fluid (ICF) ~CORRECT ANSWER~✓✓-Fluid within the
cells

-2/3 of body fluid is found within the cells



Extracellular fluid (ECF) ~CORRECT ANSWER~✓✓-Interstitial - fluid
between the cells

-Intravascular - vessels, blood

-Transcellular - specialized fluids such as synovial fluid, cerebrospinal
fluid, digestive juices, peritoneal fluid, pleural fluid...



The 2 types of movement of fluids/electrolytes ~CORRECT
ANSWER~✓✓-Passive transport

-Active transport



Passive transport ~CORRECT ANSWER~✓✓No energy is expended to
move substances. There are 3 different types of passive transport;
diffusion, osmosis, and filtration.



Active transport ~CORRECT ANSWER~✓✓ATP is required to move
substances from a low concentration to a high concentration.

,Diffusion ~CORRECT ANSWER~✓✓The passive movement of solute
molecules through a permeable membrane from [high] to [low]



Solute ~CORRECT ANSWER~✓✓The particles dissolved in the solution



Solvent ~CORRECT ANSWER~✓✓The liquid substance that contains
the solute



Osmosis ~CORRECT ANSWER~✓✓The movement of water across a
permeable membrane from low concentration of solute to high
concentration of solute



Osmolarity ~CORRECT ANSWER~✓✓The total concentration of all
solute particles in a solution. Osmolarity is classified as;

-Hypotonic

-Hypertonic

-Isotonic



Hypertonic solution ~CORRECT ANSWER~✓✓A solution in which the
concentration of solutes is greater than that of the cell that resides in
the solution. Meaning there is more "salt" in the solution than in the
RBC so water will leave RBC and they will crenate.

, Hypotonic solution ~CORRECT ANSWER~✓✓A solution in which the
concentration of solutes is less than that of the cell that resides in the
solution. Meaning there is more "salt" inside the RBC so water will
enter the RBC and they will lyse.



Filtration ~CORRECT ANSWER~✓✓Movement of both water and
small molecules through a semi-permeable membrane from an area of
high pressure to low pressure.

Filtration occurs due to hydrostatic pressure balanced with osmotic
pressure.



Hydrostatic Pressure ~CORRECT ANSWER~✓✓-Pressure exerted by a
fluid within a closed system

-Force of the weight of water molecules pressing against confining walls

-Moves from high pressure to low pressure



Osmotic Pressure ~CORRECT ANSWER~✓✓-The power of a solution to
draw water

-A highly concentrated solution draws water

-For example an artery has high pressure that travels by cells and
"bathes" them, then at the venous side fluid is drawn back into the
artery via osmotic pressure.



What structure regulates thirst in the body? ~CORRECT
ANSWER~✓✓Hypothalamus - it tests the tonicity of the blood and
decides if we need more water or not