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Flashcards in Chapter 25 Deck (32):

List the factors that influence the percentage of body fluid

Age of an individual and relative amounts of adipose connective tissue and skeletal muscle tissue


Explain the significance of percentage of body fluid relative to fluid balance

The lower percentage of body fluid, the more likely to experience a fluid imbalance


Fluid within our cells; composed of potassium, magnesium cations, phosphate anion, negatively charged proteins



Includes both intracellular fluid and blood plasma; contains sodium, calcium cations, chloride, bicarbonate anions; contains more proteins compared to ICF



Explain how fluid moves between the major body fluid compartments

Responds to osmolarity changes through osmosis. Water will move into a compartment to balance out the water concentration. Moves from hypotonic to hypertonic.


Fluid intake is equal to fluid output and a normal distribution of water and solutes is present in the ICF and ECF

Fluid Balance


Addition of water to the body, includes preformed water and metabolic water

Fluid intake


water absorbed from food and drink taken into the GI tract

Preformed water


Includes water produced daily from aerobic cellular respiration and dehydration synthesis

Metabolic water


loss of water from the body

Fluid output


How is fluid lost from the body?

Fluid is lost through breathing, sweating, cutaneous transpiration (evaporation of water directly through the skin), defecation, urination


fluid output does not equal fluid intake or when fluid is distributed unevenly

Fluid imbalance


Isotonic fluid loss is greater than isotonic fluid gain

Volume depletion


What are some examples of volume depletion?

hemorrhage, severe burns, diarrhea, chronic vomiting, hyposecretion of aldosterone


Isotonic fluid gain is greater than isotonic fluid loss; results when fluid intake is normal, but decreased fluid loss through the kidneys

Volume excess


What are some examples of volume excess?

renal failure, aldosterone hypersecretion


Water loss is greater than the loss of solutes and blood plasma becomes hypertonic



What are some examples of dehydration?

profuse sweating, diabetes mellitus, intake of alcohol, hypo secretion of ADH, insufficient water intake, over exposure to the cold


Caused by blood plasma becoming hypotonic and fluid moving from blood plasma to ICF and then into the cells; cells will swell with water

Hypotonic hydration


What are some examples of hypotonic hydration?

ADH hypersecretion, and not drinking electrolytes after excessive sweating


Total body fluid is normal but distributed unequally; fluid accumulates in a particular location but not available to use elsewhere

Fluid sequestration


What are some examples of fluid sequestration?

edema hemorrhage, pericardial effusion, pleural effusion, ascites


Describe the stimuli that increase fluid intake

Decreased salivary secretions, increased blood osmolarity, decreased blood pressure


Describe the stimuli that decrease fluid intake

Increased salivary secretions, distension of the stomach, decreased blood osmolarity, increase in blood pressure


Explain the stimulus for angiotensinogen II formation

Low blood pressure or stimulation by the sympathetic division


Explain the four primary effects of angiotensin II

Stimulates vasoconstriction of systemic blood vessels, decrease urine output, stimulates the thirst center in hypothalamus, stimulates hypothalamus and posterior pituitary to release ADH and aldosterone


Explain the stimulus for the release of ADH from the posterior pituitary

Released in response to nerve signals from the hypothalamus; low blood pressure, low blood volume, increase in blood osmolarity


What are the 3 actions of ADH?

Stimulates the thirst center, increases water absorption of the kidneys by increasing the number of aquaporins in the tubular membrane, vasoconstriction of systemic blood vessels that increase peripheral resistance


Explain the stimulus for the release of aldosterone

Response to angiotensin II, decreased blood plasma sodium levels, increased blood plasma potassium levels


Describe the changes that occur in response to the binding of aldosterone by the kidney cells

Bind to principle cells in the kidneys that cause an increased reabsorption and retention of sodium and water and increased secretion of potassium by increasing the number of sodium potassium channels


Describe the stimulus for the release of atrial natriuretic peptide

Increased stretch of hear chambers from an increased blood volume and blood pressure


Decreases blood volume and blood pressure by binding onto…

1.Blood vessels: dilates systemic blood vessels, decreasing total peripheral resistance

2. Kidneys: causes vasodilation of afferent arterioles in the kidneys and relaxation of mesangial cells; increase glomerular filtration rate