Water, Electrolyte, and Acid-Base Balance

Flashcards covering the key concepts from lecture notes on water, electrolyte, and acid-base balance in the body.

Where is water located in the body?

2/3 intracellular fluid (inside of cell), 1/3 extracellular fluid (outside of cell)

What is the largest part of the extracellular fluid?

interstitial fluid between the cells, plasma, lymph

What is a small amount of fluid in the extracellular fluid?

transcellular fluid

What are the key differences in electrolytes between intracellular and extracellular fluid?

Extracellular fluid is high in Na+ and Cl-, while intracellular fluid is high in K+.

Why is maintaining proper levels of ions important in body fluids?

To keep the water in the cells the same and maintain water balance.

What happens at the arteriole end of capillaries regarding water exchange?

High hydrostatic pressure pushes water out of plasma.

What happens at the venous end of capillaries regarding water exchange?

High osmotic pressure from plasma proteins pulls water back in.

How does the body gain water?

Drinking, food, and metabolism.

How does the body lose water?

Sweat, feces, across skin and lungs, and urine.

What two systems primarily regulate water balance in the body?

The central nervous system and kidneys.

How does the hypothalamus measure body water?

By measuring osmotic pressure.

What does high osmotic pressure indicate regarding body water?

Low body water.

How does the hypothalamus regulate water output?

By altering levels of ADH from the posterior pituitary.

What happens when ADH levels increase?

Water will be retained, and urine concentrated.

What happens when ADH levels decrease?

Water will be lost, and urine dilute.

What happens to cells when ECF osmotic pressure rises?

Cells shrink.

What happens to cells when ECF osmotic pressure falls?

Cells swell.

What is edema?

Accumulation of water in the tissues.

Name factors that can cause edema.

Low plasma proteins, blocked lymph vessels, elephantiasis, leaky veins, inflammation.

What is the primary function of the Renin-Angiotensin system?

Regulation of sodium ions (Na+).

What triggers the release of renin from JG cells?

Low blood pressure or high filtrate osmolarity.

What does increased Angiotensin II stimulate?

Aldosterone release from the adrenal cortex.

What does aldosterone cause in the renal tubules?

Increased reabsorption of Na+ ions and release of K+ ions.

What are the results of aldosterone release?

Increased water retention and increased blood pressure.

How are calcium ions (Ca++) regulated?

By parathyroid hormone (PTH).

Where is calcium stored in the body?

Bone.

What is the main control of Ca++ in plasma?

Parathyroid hormone (PTH).

What are the actions of PTH?

Causes reabsorption of Ca++ from bone, reabsorption of Ca++ by the kidney, and production of the active form of vitamin D (calcitriol).

What is the role of calcitriol?

Helps absorb Ca++ from the intestine.

What are the sources of hydrogen ions (H+) in the body?

Metabolic processes, aerobic respiration, anaerobic respiration, lactic acid, breakdown of fats and ketone bodies.

What are buffers?

Substances that stabilize pH of a solution.

What is the function of buffers?

Minimize pH changes in body fluids.

Name the three chemical buffering systems in the body.

Bicarbonate system, phosphate system, and protein system.

How does the respiratory system excrete carbon dioxide (CO2)?

By increasing breathing rate and depth when H+ is too high.

How does CO2 in the plasma affect pH?

Causes addition of H+ ions to the plasma, acidifying the blood.

How do the kidneys contribute to acid-base balance?

Induce tubular secretion of H+.

What is the normal range of pH values for plasma?

7.35 to 7.45

What is acidosis?

Low plasma pH.

What is alkalosis?

High plasma pH.

What is respiratory acidosis?

Low pH due to breathing issues, low rate and depth of breathing.

What is metabolic acidosis?

Lowering of plasma pH due to a metabolic issue, kidney failure, diabetes mellitus, diarrhea and vomiting.

What is respiratory alkalosis?

Hyperventilation.

What is metabolic alkalosis?

Factors other than breathing increase plasma pH, vomiting, antacids.

What are the components of extracellular fluid?

Interstitial fluid, plasma, lymph, and transcellular fluid.

What is the role of lymph vessels in water exchange?

Returns water lost at the capillaries back to the blood.

How is water intake regulated by the CNS?

Hypothalamus measures body water by measuring osmotic pressure, which triggers thirst.

What are the factors associated with Sodium ion Regulation?

Renin-angiotensin system

What can cause metabolic acidosis?

kidney failure, diabetes mellitus, diarrhea and vomiting

What can cause metabolic akalosis?

Vomiting and antacids.

What stimulates aldosterone release from adrenal cortex?

Angiotensin II

Name two things that happen when high proton levels are met.

Increased breathing rate and depth

Name three Electrolyte regulations

Flow Chart. Regulation of sodium ions (Na+), Regulation of calcium ions (Ca++) by PTH.

What are some main sources of H+ that disrupt acid-base balance?

metabolic processes, aerobic respiration, anaerobic respiration, lactic acid,breakdown of fats and ketone bodies

What mechanisms are in place to regulate acid-base balance?

chemical buffering systems, respiratory excertion of carbon dioxide (CO2), renal excertion of hydrogen ions

How much body water is in extracellular fluid?

1/3

How much body water is in the intracellular fluid?

2/3

Where does the body receive water from?

drinking, food and metabolism

What causes water to come back into the blood at at the venous end

plasma has high levels of proteins, high osmotic pressure.

What is the relationship between salt balance and water balance?

Water balance is regulated by the central nervous system and kidneys. Coordinated with salt balance.

What is the relationship between blood pressure and water balance?

Water balance is regulated by the central nervous system and kidneys. Coordinated with maintenance of blood pressure.

What system is used for the regulartion of sodium ions?

Renin-angiotensin system

What is the main control of calcium ions in plasma?

parathyroid hormone (PTH)

How does CO2 effect the acidity of blood?

CO2 in the plasma causes addition of H+ ions to the plasma, Blood is constantly being acidified.

What are the theee chemical buffer systems?

bicarbonate system, phosphate system and protein system

What is the pH range of plasma

7.35 to 7.45

Fluid within cells.

Intracellular Fluid

Fluid outside of cells.

Extracellular Fluid

A hormone released that stimulates the reabsorption of water, leading to more concentrated urine.

ADH, antidiuretic hormone.

Where does the stimulus for thirst originate?

Hypothalamus

What electrolyte is located more intracellularly?

Potassium

What electrolytes are located more extracellularly?

Sodium and Chloride

What is the role of proteins in the plasma in regards to water exchange at the capillaries?

They cause the plasma to have high osmotic pressure, allowing water to come back in at the venous end.

What mechanism can cause water imbalances and cause cells to shrink or swell?

ECF osmotic pressure

How do chemical buffer systems work?

Buffers minimize pH changes in body fluids. Buffers are substances that stabilize pH of a solution.

Where is water located in the body?

2/3 intracellular fluid, 1/3 extracellular fluid-interstitial fluid between the cells, plasma, lymph, transcellular fluid.

What are the key differences in electrolytes between intracellular and extracellular fluid?

Extracellular fluid is high in Na+ and Cl-, while intracellular fluid is high in K+.

Why is maintaining proper levels of ions important in body fluids?

To keep the water in the cells the same and maintain water balance.

What happens at the arteriole end of capillaries regarding water exchange?

High hydrostatic pressure pushes water out of plasma.

What happens at the venous end of capillaries regarding water exchange?

High osmotic pressure from plasma proteins pulls water back in.

How does the body gain water?

Drinking, food, and metabolism.

How does the body lose water?

Sweat, feces, across skin and lungs, and urine.

What two systems primarily regulate water balance in the body?

The central nervous system and kidneys.

How does the hypothalamus measure body water?

By measuring osmotic pressure.

What does high osmotic pressure indicate regarding body water?

Low body water.

How does the hypothalamus regulate water output?

By altering levels of ADH from the posterior pituitary.

What happens when ADH levels increase?

Water will be retained, and urine concentrated.

What happens when ADH levels decrease?

Water will be lost, and urine dilute.

What happens to cells when ECF osmotic pressure rises?

Cells shrink.

What happens to cells when ECF osmotic pressure falls?

Cells swell.

What is edema?

Accumulation of water in the tissues.

Name factors that can cause edema.

Low plasma proteins, blocked lymph vessels, elephantiasis, leaky veins, inflammation.

What is the primary function of the Renin-Angiotensin system?

Regulation of sodium ions (Na+).

What triggers the release of renin from JG cells?

Low blood pressure or high filtrate osmolarity.

What does increased Angiotensin II stimulate?

Aldosterone release from the adrenal cortex.

What does aldosterone cause in the renal tubules?

Increased reabsorption of Na+ ions and release of K+ ions.

What are the results of aldosterone release?

Increased water retention and increased blood pressure.

How are calcium ions (Ca++) regulated?

By parathyroid hormone (PTH).

Where is calcium stored in the body?

Bone.

What is the main control of Ca++ in plasma?

Parathyroid hormone (PTH).

What are the actions of PTH?

Causes reabsorption of Ca++ from bone, reabsorption of Ca++ by the kidney, and production of the active form of vitamin D (calcitriol).