Body Fluids Flashcards
Body fluids make up over half the body mass; primarily composed of
Water
Electrolytes
Nutrients
Gases
Wastes
What maintains composition and volume of body fluids
Negative feedback mechanism
Water acts as a
Solvent
Transport medium
Participant in metabolism
Importance of water in body fluid maintenance (important factor in homeostasis) 4 factors
Thirst mechanism (maintains volume)
Kidney activity
Hormones
Buffers, respiration and kidney function regulate pH
What are the 2 main fluid compartments
Intracellular fluid (ICF)
Extra cellular fluid (ECF)
Extracellular fluid can be
Lymph
Blood Plasma
Interstitial fluid
Fluid in special compartments (ex. Cerebrospinal fluid)
Electrolytes are an important component of body fluid. What do they do?
Conduct an electrical current in solution
Electrolytes compounds separate into
Positive and negative ions in solution
Positive ions are
Cations
List the 4 positive ions
Sodium
Potassium
Calcium
Magnesium
List 3 negative ions
Phosphate
Chloride
Bicarbonate
Sodium (main + ion in ECF) is required for? What does it maintain?
Required for nerve impulse conduction
Maintains osmotic balance and body fluid volume; acid/base balance
Potassium (main + ion in ICF) is required for? What does it regulate?
Required for nerve impulse conduction
Regulates chemical rxns (carbohydrate to energy and amino acid to protein)
What is calcium required for
Bone formation
Muscle contraction
Nerve impulse transmission
Blood clotting
What is magnesium required for
Muscle contraction
Phosphate is found in
Plasma membranes
DNA and RNA and ATP
Phosphate is essential for
Carbohydrate metabolism
Bone formation
Acid-base balance
Chloride is essential for
Formation of hydrochloric acid in the stomach
Helps regulate fluid balance and pH
What is the most abundant anion in ECF
Chloride
we gain water from
food, beverages, cellular respiration
we lose water from
skin
kidney
lungs
intestinal tract
3 main factors that are mechanisms for balancing fluid volumes
-regulating fluid output
-regulating fluid input
-exchanging fluids btw compartments and from place to place in the body
fluid homeostasis is maintained by
water intake and urine output
control of water intake happens by means of (3)
thirst mechanisms
control center for thirst
hormone regulation
what is polydipsia
excessive thirst
control center for thirst is located in the
hypothalmus
a decrease in fluid volume results in
thirst
what are the main regulators of water and electrolyte balance
kidneys
what is critical for water balance
sodium
hormone regulation controls
thirst and urine output
hormone aldosterone is found in the
adrenal cortex
if you have a aldosterone deficiency you may have what disease
addison disease
(Na+ & H2O low, K+ in excess)
Antidiuretic hormone (ADH) is found in the
pituitary
what hormone stimulates production of both aldosterone and ADH
angiotensin II (ATII)
what does the hormone atrial natriuretic peptide (ANP) do
promotes lower Na+ and H2O, thereby lowering blood volume and BP
body fluids have a normal pH of
7.35-7.45
three tenths f a point shift in pH in either direction is ? (7.0-7.7)
fatal
what provides short term regulation of CO2?
respiration
- can increase blood pH by exhaling more CO2
- can decrease blood pH by inhaling more CO2
what provides long term regulation of pH by reabsorbing or eliminating H+ as needed
kidney function
what is characterized by a pH less that 7.35, which depresses nervous system and causes mental confusion or coma
acidosis
Causes of acidosis may include
-respiratory obstruction or lung disease that prevents release of CO2
-kidney failure
-prolonged diarrhea
-intense long term exercise
what is characterized by pH greater than 7.45, excites nervous system (tingling, muscle twitches, paralysis)
alkalosis
possible causes of alkalosis include
hyperventilation
ingestion of to much antacid
prolonged vomiting with loss of stomach acids
Excess fluid in the lungs is called
pulmonary edema
(often results from congestive heart failure)
Hyponatremia is aka
water intoxication
what are the characteristics of hyponatremia (water intoxication)
reduced blood Na+ concentration
Swelling in brain may lead to convulsions, coma, death
Effusion refers to
escape of fluid into a space or cavity
(difficult to inhale)
Ascites refers to
fluid between abdominal cavity and organs
(malnutrition/kwashiorkor, cancer, infection, disorders of liver, heart and kidneys)
Pleural effusions is fluid within pleural space. What diseases or disorders may be associated with this
tuberculosis, cancer, infection
pericardial effusion fluid is
enclosing heart
fluid therapy refers to
fluids administered through IV to correct specific imbalances
what are the 3 solutions administered in fluid therapy
- Isotonic solution (administered most often)
- hypertonic solution
- hypotonic solution
