Week 4: Fluid and electrolytes Flashcards
Define
Sodium Concentration
The level of sodium ions in body fluids, which influences fluid balance, blood pressure, and osmolarity.
What is
The regulation of water content in the blood plasma to ensure appropriate blood volume and pressure.
Plasma Water Balance
Define
Cell Swelling (Lysis)
The expansion and rupture of cells due to excessive water intake in a hypotonic environment.
Define
Carbonic Acid-Bicarbonate Buffer System
A major buffer system in the blood that regulates pH by balancing carbonic acid and bicarbonate ions.
What is
A hormone system that regulates blood pressure and fluid balance by controlling sodium reabsorption and blood volume.
Renin-Angiotensin-Aldosterone System (RAAS)
Define
Adrenal Cortex
The outer layer of the adrenal glands that produces hormones such as aldosterone, influencing fluid and electrolyte balance.
What is
The liquid component of blood that carries cells, hormones, and nutrients, and is involved in maintaining blood volume and pressure.
Plasma
Define
Intracellular Fluid
Fluid located within cells, making up about 60% of total body fluid and containing high concentrations of potassium and phosphate ions.
Define
Oliguria
Reduced urine output, often indicating dehydration or renal dysfunction.
What is
The pressure exerted by blood within capillaries, influencing fluid movement into and out of tissues.
Capillary Hydrostatic Pressure
What is
A metabolic disorder characterized by high blood glucose levels and potential associated fluid imbalances.
Diabetes Mellitus
What is
A hormone produced by the adrenal cortex that increases sodium reabsorption and potassium excretion in the kidneys, affecting fluid balance and blood pressure.
Aldosterone
Define
Crenation
The shrinkage of cells due to water loss in a hypertonic environment.
Define
Lymphedema
Swelling due to the accumulation of lymph fluid, often resulting from damage to the lymphatic system.
What is
A condition characterized by a loss of water from the extracellular fluid, typically with water loss exceeding sodium ion loss, leading to increased plasma osmolarity and potential cell shrinkage.
Dehydration
What is
The pressure required to prevent water from moving across a semipermeable membrane due to solute concentration differences.
Osmotic Pressure
Define
Capillary Hydrostatic Pressure
The pressure exerted by blood within capillaries, influencing fluid movement into and out of tissues.
True or False: A solution with a high concentration of hydrogen ions will have a pH > 7.
False
What is
Charged particles (ions) in body fluids that help regulate fluid balance, muscle function, and nerve signaling. Common electrolytes include sodium, potassium, chloride, and bicarbonate.
Electrolytes
Define
Posterior Pituitary
The gland that releases ADH and oxytocin, playing a role in fluid balance and endocrine regulation.
Define
Interstitial Fluid
Fluid that surrounds cells in tissues, providing nutrients and removing waste products; part of the extracellular fluid.
What is
Systems that regulate physiological processes by providing feedback to maintain homeostasis, including fluid and electrolyte balance.
Feedback Mechanisms
What is
The level of sodium ions in body fluids, which influences fluid balance, blood pressure, and osmolarity.
Sodium Concentration
What is
A peptide hormone that constricts blood vessels and stimulates aldosterone release, increasing blood pressure and fluid retention.
Angiotensin II
The fluid inside blood vessels is called __________ and is part of the __________
The fluid inside blood vessels is called PLASMA and is part of the ECF
Define
Osmolarity
The concentration of solutes in a solution, expressed as osmoles per liter, which determines the osmotic pressure and influences fluid movement.
Define
Metabolic Alkalosis
A condition characterized by an increase in blood pH due to excessive bicarbonate or decreased acid levels.
What is
The space between cells in tissues where interstitial fluid is located.
Interstitial Space
Define
Hypertonic
A condition where the osmolarity of a solution is higher than that of body fluids, causing water to move out of cells and into the extracellular space.
Define
Isotonic Conditions
A state where the osmolarity of body fluids is balanced, causing no net movement of water between compartments.
Define
Osmosis
The movement of water across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration to equalize concentrations.
What is
Increased urine output due to the presence of high levels of solutes (such as glucose) in the urine, which pulls water out of the body.
Osmotic Diuresis
What is
The minimum amount of water the body must excrete to remove metabolic wastes, including urine and insensible losses.
Obligatory Water Losses
Define
Cerebral Edema
Swelling of brain tissue due to fluid accumulation, which can result from conditions such as hyponatremia or head trauma.
What is
The regulation of fluid levels within cells to maintain proper cell function and volume.
Intracellular Fluid Balance
What is
Ions that help buffer the blood by reacting with excess hydrogen ions to form carbonic acid.
Bicarbonate Ions
Define
Synovial Fluid
Lubricating fluid found in joint cavities, reducing friction between articular cartilage and aiding in joint movement.
Define
Fluid Balance
The equilibrium between fluid intake and output, ensuring that body fluids are maintained at appropriate levels for physiological function.
What is
The shrinkage of cells due to water loss in a hypertonic environment.
Crenation
Define
Renin-Angiotensin-Aldosterone System (RAAS)
A hormone system that regulates blood pressure and fluid balance by controlling sodium reabsorption and blood volume.
Define
Diabetes Mellitus
A metabolic disorder characterized by high blood glucose levels and potential associated fluid imbalances.
What is
Increased breathing rate, leading to decreased carbon dioxide levels and respiratory alkalosis.
Hyperventilation
What is
Impaired kidney function that can affect fluid and electrolyte balance and lead to accumulation of waste products.
Renal Insufficiency
Define
Water Intoxication
A condition resulting from excessive water intake, leading to dilution of electrolytes and potential cellular swelling.
Define
Solute Concentration
The amount of solute present in a given volume of solution, affecting osmolarity and fluid movement.
What is
The process by which the kidneys excrete potassium into the filtrate to maintain electrolyte balance and prevent hyperkalemia.
Potassium Secretion
Define
Hyponatremia
Low sodium levels in the blood, often due to excessive water intake or sodium loss.
Define
Carbonic Acid
An acid (H₂CO₃) formed from carbon dioxide and water, which dissociates into bicarbonate and hydrogen ions.
What is
The increased production of urine, which can result from hormonal changes or pharmacological agents that promote fluid loss.
Diuresis
What is
Sensors located in blood vessels that detect changes in blood pressure and help regulate fluid balance by influencing kidney function and vascular tone.
Baroreceptors
What is
The pressure exerted by a fluid due to its weight, which affects the movement of fluids across capillary walls and contributes to fluid exchange.
Hydrostatic Pressure
What is
The process of producing energy with oxygen, which affects carbon dioxide levels and pH balance.
Aerobic Respiration
What is
Sensors in the hypothalamus that detect changes in blood osmolarity and regulate thirst and antidiuretic hormone (ADH) release.
Osmoreceptors
The fluid inbetween cells within tissues is called _________ while the fluid inside cells is called __________
The fluid inbetween cells within tissues is called ISF while the fluid inside cells is called ICF
What is
A condition characterized by decreased blood volume, which can result from fluid loss or inadequate fluid intake.
Hypovolemia
Define
Baroreceptors
Sensors located in blood vessels that detect changes in blood pressure and help regulate fluid balance by influencing kidney function and vascular tone.
What is
A major buffer system in the blood that regulates pH by balancing carbonic acid and bicarbonate ions.
Carbonic Acid-Bicarbonate Buffer System
What is
The essential fluid losses required for the elimination of metabolic waste and maintaining fluid balance, including insensible and urine losses.
Obligatory Losses
Define
Hemorrhage
Excessive blood loss that can lead to decreased blood volume, hypovolemia, and potential shock.
Define
Edema
Abnormal accumulation of fluid in the interstitial space, causing swelling of tissues, often due to increased capillary hydrostatic pressure, increased capillary permeability, or decreased colloid osmotic pressure.
Define
Hypovolemia
A condition characterized by decreased blood volume, which can result from fluid loss or inadequate fluid intake.
Define
Thirst Mechanism
The physiological drive to consume fluids in response to increased blood osmolarity or decreased blood volume.
What is
Fluid that surrounds cells in tissues, providing nutrients and removing waste products; part of the extracellular fluid.
Interstitial Fluid
What is
The processes by which fluids are consumed (intake) and expelled from the body (output), including through urine, feces, sweat, and respiration.
Fluid Intake and Output
What is
Organs that regulate fluid and electrolyte balance by filtering blood, excreting waste, and maintaining acid-base balance through reabsorption and secretion processes.
Kidneys
Define
Metabolic Acidosis
A condition characterized by a decrease in blood pH due to increased acid production or decreased bicarbonate levels.
What is
Abnormal accumulation of fluid in the interstitial space, causing swelling of tissues, often due to increased capillary hydrostatic pressure, increased capillary permeability, or decreased colloid osmotic pressure.
Edema
Define
Plasma Proteins
Proteins in blood plasma, such as albumin, that contribute to colloid osmotic pressure and fluid balance.
What is
Reduced urine output, often indicating dehydration or renal dysfunction.
Oliguria
Define
Hydrostatic Pressure
The pressure exerted by a fluid due to its weight, which affects the movement of fluids across capillary walls and contributes to fluid exchange.
Define
Adipose Tissue
Body tissue primarily composed of fat cells, which stores energy and contributes to the overall fluid balance by affecting tissue hydration.
Define
Diabetes Insipidus
A condition characterized by inadequate ADH production or response, leading to excessive urine output and thirst.
What is
Cells lining the blood vessels and lymphatic vessels, involved in regulating fluid exchange and maintaining vascular permeability.
Endothelial Cells
What is
Swelling due to the accumulation of lymph fluid, often resulting from damage to the lymphatic system.
Lymphedema
Define
Transcellular Fluids
Specialized fluids located in specific body compartments, such as cerebrospinal fluid, synovial fluid, and ocular humors.
What is
A state where the osmolarity of body fluids is balanced, causing no net movement of water between compartments.
Isotonic Conditions
What is
The concentration of solutes in blood plasma, affecting fluid distribution between compartments.
Plasma Osmolarity
Define
Dehydration
A condition characterized by a loss of water from the extracellular fluid, typically with water loss exceeding sodium ion loss, leading to increased plasma osmolarity and potential cell shrinkage.
What is
Fluid located outside cells, including interstitial fluid, plasma, and transcellular fluid. It contains high concentrations of sodium and chloride ions.
Extracellular Fluid
What isWhat is
A condition where the osmolarity of a solution is lower than that of body fluids, causing water to move into cells and potentially leading to cell swelling.
Hypotonic
What is
A condition resulting from decreased carbon dioxide levels in the blood due to hyperventilation.
Respiratory Alkalosis
Define
Respiratory Acidosis
A condition resulting from increased carbon dioxide levels in the blood due to impaired respiratory function.
Define
Diuresis
The increased production of urine, which can result from hormonal changes or pharmacological agents that promote fluid loss.
Define
Non-electrolytes
Substances that do not dissociate into ions in solution, such as glucose and urea, which still affect fluid balance but do not contribute to osmotic pressure.
What is
Substances dissolved in body fluids, including electrolytes, nutrients, and waste products, which influence fluid balance and osmolarity.
Solutes
What is
The physiological drive to consume fluids in response to increased blood osmolarity or decreased blood volume.
Thirst Mechanism
True or False: Normal cell and tissue function only occurs between an ECF pH of 7.35-7.45
True
What is
A condition where excessive water intake dilutes the extracellular fluid, causing a decrease in osmolarity and leading to water moving into cells, potentially causing cell swelling and cerebral edema.
Hypotonic Hydration
What is
Mechanisms that help maintain pH balance by neutralizing excess acids or bases in the body.
Chemical Buffer Systems
Define
Nephron
The functional unit of the kidney responsible for filtering blood, reabsorbing nutrients, and excreting waste.
Define
Intracellular Fluid Balance
The regulation of fluid levels within cells to maintain proper cell function and volume.
What is
The concentration of solutes in a solution, expressed as osmoles per liter, which determines the osmotic pressure and influences fluid movement.
Osmolarity
What is
The movement of water across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration to equalize concentrations.
Osmosis
What is
The gland that releases ADH and oxytocin, playing a role in fluid balance and endocrine regulation.
Posterior Pituitary
Define
Bicarbonate
An ion (HCO₃⁻) that acts as a buffer to maintain pH balance in the blood and other fluids.
What is
The narrowing of blood vessels, which can increase blood pressure and affect fluid distribution.
Vasoconstriction
What is
Elevated sodium levels in the blood, often associated with dehydration and increased thirst.
Hypernatremia
Define
Capillary Walls
The thin walls of capillaries that facilitate the exchange of fluids, gases, and nutrients between blood and tissues.
Define
Feedback Mechanisms
Systems that regulate physiological processes by providing feedback to maintain homeostasis, including fluid and electrolyte balance.
What is
An ion (HCO₃⁻) that acts as a buffer to maintain pH balance in the blood and other fluids.
Bicarbonate
What is
Fluid losses that cannot be easily measured, including evaporation from the skin and respiratory tract.
Insensible Losses
Define
Chemical Buffer Systems
Mechanisms that help maintain pH balance by neutralizing excess acids or bases in the body.
Define
Aerobic Respiration
The process of producing energy with oxygen, which affects carbon dioxide levels and pH balance.
Define
Alkalosis
A condition characterized by a deficiency of hydrogen ions in the blood, leading to an increase in pH.
What is
The mechanisms and processes involved in keeping fluid levels within the body stable, including intake, output, and distribution.
Fluid Balance Maintenance
Define
Cerebrospinal Fluid
Clear fluid surrounding the brain and spinal cord, providing cushioning and nutrient exchange for the central nervous system.
A patient is suffering from metabolis acidosis. This means that the pH of the ECF will be:
low due to a high concentration of hydrogen ions
Define
Respiratory Membrane
The barrier between the alveoli and blood in the lungs where gas exchange occurs.
What is
Disorders affecting kidney function, which can disrupt fluid and electrolyte balance and lead to various symptoms.
Kidney Disease
What is
The outer layer of the adrenal glands that produces hormones such as aldosterone, influencing fluid and electrolyte balance.
Adrenal Cortex
Define
Hypothalamus
A brain region involved in regulating thirst, ADH secretion, and overall fluid balance.
What is
Fluids secreted by serous membranes, reducing friction between organs and body walls; examples include pleural fluid and peritoneal fluid.
Serous Fluids
Define
Endothelial Cells
Cells lining the blood vessels and lymphatic vessels, involved in regulating fluid exchange and maintaining vascular permeability.
What is
Proteins in blood plasma, such as albumin, that contribute to colloid osmotic pressure and fluid balance.
Plasma Proteins
Define
Capillary Permeability
The ability of capillary walls to allow substances to pass through, affecting fluid exchange between blood and tissues.
Define
Serous Fluids
Fluids secreted by serous membranes, reducing friction between organs and body walls; examples include pleural fluid and peritoneal fluid.
Define
Interstitial Space
The space between cells in tissues where interstitial fluid is located.
What is
A hormone released by the posterior pituitary that promotes water reabsorption in the kidneys, helping to regulate blood volume and osmolarity.
Antidiuretic Hormone (ADH)
Define
Plasma Water Balance
The regulation of water content in the blood plasma to ensure appropriate blood volume and pressure.
Define
Hypernatremia
Elevated sodium levels in the blood, often associated with dehydration and increased thirst.
Define
Body Fluid Compartments
The various areas within the body where fluids are located, including intracellular fluid (inside cells), extracellular fluid (outside cells), and transcellular fluid (in specific compartments like cerebrospinal fluid and synovial fluid).
Define
Liver Disease
Conditions affecting the liver, which can impact protein synthesis and fluid balance, leading to edema and other issues.
What is
The ability of capillary walls to allow substances to pass through, affecting fluid exchange between blood and tissues.
Capillary Permeability
What is
Substances that do not dissociate into ions in solution, such as glucose and urea, which still affect fluid balance but do not contribute to osmotic pressure.
Non-electrolytes
Define
Sodium Reabsorption
The process by which the kidneys reabsorb sodium from the filtrate back into the blood, helping to maintain fluid balance and blood pressure.
Define
Vasoconstriction
The narrowing of blood vessels, which can increase blood pressure and affect fluid distribution.
Define
Aldosterone
A hormone produced by the adrenal cortex that increases sodium reabsorption and potassium excretion in the kidneys, affecting fluid balance and blood pressure.
What is
An acid (H₂CO₃) formed from carbon dioxide and water, which dissociates into bicarbonate and hydrogen ions.
Carbonic Acid
Define
Bicarbonate Ions
Ions that help buffer the blood by reacting with excess hydrogen ions to form carbonic acid.
Define
Pituitary Tumors
Abnormal growths in the pituitary gland that can affect hormone production and fluid balance.
What is
Fluids within the eye, including aqueous humor (in the anterior chamber) and vitreous humor (in the posterior chamber), which maintain intraocular pressure and provide nourishment.
Ocular Humors
What is
Lubricating fluid found in joint cavities, reducing friction between articular cartilage and aiding in joint movement.
Synovial Fluid
What is
Fluid located within cells, making up about 60% of total body fluid and containing high concentrations of potassium and phosphate ions.
Intracellular Fluid
Define
Plasma Osmolarity
The concentration of solutes in blood plasma, affecting fluid distribution between compartments.
What is
Abnormal growths in the pituitary gland that can affect hormone production and fluid balance.
Pituitary Tumors
What is
A condition resulting from increased carbon dioxide levels in the blood due to impaired respiratory function.
Respiratory Acidosis
What is
The thin walls of capillaries that facilitate the exchange of fluids, gases, and nutrients between blood and tissues.
Capillary Walls
Define
Acidosis
A condition characterized by an excess of hydrogen ions in the blood, leading to a decrease in pH.
Define
Ocular Humors
Fluids within the eye, including aqueous humor (in the anterior chamber) and vitreous humor (in the posterior chamber), which maintain intraocular pressure and provide nourishment.
What is
A brain region involved in regulating thirst, ADH secretion, and overall fluid balance.
Hypothalamus
What is
A condition characterized by a decrease in blood pH due to increased acid production or decreased bicarbonate levels.
Metabolic Acidosis
What is
A condition characterized by an excess of hydrogen ions in the blood, leading to a decrease in pH.
Acidosis
Define
Extracellular Fluid
Fluid located outside cells, including interstitial fluid, plasma, and transcellular fluid. It contains high concentrations of sodium and chloride ions.
Define
Obligatory Water Losses
The minimum amount of water the body must excrete to remove metabolic wastes, including urine and insensible losses.
Define
Plasma
The liquid component of blood that carries cells, hormones, and nutrients, and is involved in maintaining blood volume and pressure.
What is
The expansion and rupture of cells due to excessive water intake in a hypotonic environment.
Cell Swelling (Lysis)
What is
A condition resulting from excessive water intake, leading to dilution of electrolytes and potential cellular swelling.
Water Intoxication
Define
Hypoventilation
Reduced breathing rate, leading to increased carbon dioxide levels and respiratory acidosis.
What is
The amount of solute present in a given volume of solution, affecting osmolarity and fluid movement.
Solute Concentration
What is
The regulation of pH through the control of carbon dioxide levels via breathing.
Respiratory Mechanism
Define
Muscle Tissue
Tissue composed of muscle cells that can influence fluid distribution and electrolyte balance through its activity and metabolism.
Define
Kidney Disease
Disorders affecting kidney function, which can disrupt fluid and electrolyte balance and lead to various symptoms.
Define
Hypotonic
A condition where the osmolarity of a solution is lower than that of body fluids, causing water to move into cells and potentially leading to cell swelling.
What is
The process by which the kidneys reabsorb sodium from the filtrate back into the blood, helping to maintain fluid balance and blood pressure.
Sodium Reabsorption
Define
Lymph
Fluid that circulates through the lymphatic system, helping to remove interstitial fluid and transport immune cells.
What is
The barrier between the alveoli and blood in the lungs where gas exchange occurs.
Respiratory Membrane
The most common cation in the ECF is __ ions and in the ICF is __ ions.
The most common cation in the ECF is Na ions and in the ICF is K ions.
What is
A condition where the osmolarity of a solution is higher than that of body fluids, causing water to move out of cells and into the extracellular space.
Hypertonic
Define
Obligatory Losses
The essential fluid losses required for the elimination of metabolic waste and maintaining fluid balance, including insensible and urine losses.
Define
Respiratory Mechanism
The regulation of pH through the control of carbon dioxide levels via breathing.
Define
Hypotonic Hydration
A condition where excessive water intake dilutes the extracellular fluid, causing a decrease in osmolarity and leading to water moving into cells, potentially causing cell swelling and cerebral edema.
Define
Insensible Losses
Fluid losses that cannot be easily measured, including evaporation from the skin and respiratory tract.
Define
Solutes
Substances dissolved in body fluids, including electrolytes, nutrients, and waste products, which influence fluid balance and osmolarity.
What is
Swelling of brain tissue due to fluid accumulation, which can result from conditions such as hyponatremia or head trauma.
Cerebral Edema
What is
Low sodium levels in the blood, often due to excessive water intake or sodium loss.
Hyponatremia
What is
A condition characterized by an increase in blood pH due to excessive bicarbonate or decreased acid levels.
Metabolic Alkalosis
Define
Colloid Osmotic Pressure
The osmotic pressure exerted by plasma proteins that helps retain fluid within the blood vessels.
Define
Homeostasis
The process of maintaining a stable internal environment, including fluid and electrolyte balance, despite external changes.
What is
Tissue composed of muscle cells that can influence fluid distribution and electrolyte balance through its activity and metabolism.
Muscle Tissue
Define
Renal Insufficiency
Impaired kidney function that can affect fluid and electrolyte balance and lead to accumulation of waste products.
What is
Specialized fluids located in specific body compartments, such as cerebrospinal fluid, synovial fluid, and ocular humors.
Transcellular Fluids
What is
Body tissue primarily composed of fat cells, which stores energy and contributes to the overall fluid balance by affecting tissue hydration.
Adipose Tissue
What is
Excessive blood loss that can lead to decreased blood volume, hypovolemia, and potential shock.
Hemorrhage
Define
Antidiuretic Hormone (ADH)
A hormone released by the posterior pituitary that promotes water reabsorption in the kidneys, helping to regulate blood volume and osmolarity.
What is
Fluid that circulates through the lymphatic system, helping to remove interstitial fluid and transport immune cells.
Lymph
Define
Angiotensin II
A peptide hormone that constricts blood vessels and stimulates aldosterone release, increasing blood pressure and fluid retention.
What is
The process of maintaining a stable internal environment, including fluid and electrolyte balance, despite external changes.
Homeostasis
Define
Hyperventilation
Increased breathing rate, leading to decreased carbon dioxide levels and respiratory alkalosis.
Define
Osmoreceptors
Sensors in the hypothalamus that detect changes in blood osmolarity and regulate thirst and antidiuretic hormone (ADH) release.
Define
Osmotic Diuresis
Increased urine output due to the presence of high levels of solutes (such as glucose) in the urine, which pulls water out of the body.
Define
Fluid Intake and Output
The processes by which fluids are consumed (intake) and expelled from the body (output), including through urine, feces, sweat, and respiration.
What is
Clear fluid surrounding the brain and spinal cord, providing cushioning and nutrient exchange for the central nervous system.
Cerebrospinal Fluid
What is
The equilibrium between fluid intake and output, ensuring that body fluids are maintained at appropriate levels for physiological function.
Fluid Balance
Define
Electrolytes
Charged particles (ions) in body fluids that help regulate fluid balance, muscle function, and nerve signaling. Common electrolytes include sodium, potassium, chloride, and bicarbonate.
What is
The various areas within the body where fluids are located, including intracellular fluid (inside cells), extracellular fluid (outside cells), and transcellular fluid (in specific compartments like cerebrospinal fluid and synovial fluid).
Body Fluid Compartments
What is
The functional unit of the kidney responsible for filtering blood, reabsorbing nutrients, and excreting waste.
Nephron
What is
The osmotic pressure exerted by plasma proteins that helps retain fluid within the blood vessels.
Colloid Osmotic Pressure
Define
Kidneys
Organs that regulate fluid and electrolyte balance by filtering blood, excreting waste, and maintaining acid-base balance through reabsorption and secretion processes.
Define
Osmotic Pressure
The pressure required to prevent water from moving across a semipermeable membrane due to solute concentration differences.
What is
Conditions affecting the liver, which can impact protein synthesis and fluid balance, leading to edema and other issues.
Liver Disease
Define
Respiratory Alkalosis
A condition resulting from decreased carbon dioxide levels in the blood due to hyperventilation.
What is
A condition characterized by inadequate ADH production or response, leading to excessive urine output and thirst.
Diabetes Insipidus
Define
Fluid Balance Maintenance
The mechanisms and processes involved in keeping fluid levels within the body stable, including intake, output, and distribution.
What is
A condition characterized by a deficiency of hydrogen ions in the blood, leading to an increase in pH.
Alkalosis
Define
Potassium Secretion
The process by which the kidneys excrete potassium into the filtrate to maintain electrolyte balance and prevent hyperkalemia.
What is
Reduced breathing rate, leading to increased carbon dioxide levels and respiratory acidosis.
Hypoventilation
What are the main body fluid compartments?
The main body fluid compartments are intracellular fluid (ICF) and extracellular fluid (ECF). The ECF is further divided into interstitial fluid and plasma.
How is water primarily obtained in the body?
Water is primarily obtained through ingested food and fluids, and also produced by cellular metabolism.
What is the average percentage of body water in adults?
The average adult body is about 60% water.
Why do males generally have a higher percentage of body water compared to females?
Males have a higher percentage of body water because they typically have more muscle tissue (which contains about 75% water) compared to females, who have a higher proportion of adipose tissue (which contains about 10% water).
What percentage of body weight is water in infants?
Infants have about 75% of their body weight composed of water.
How does body water content change with age?
Body water content declines with age. Older adults generally have a lower percentage of body water compared to younger individuals.
What is dehydration, and what causes it?
Dehydration is a condition resulting from a loss of more water than is taken in. Causes include inadequate fluid intake, excessive fluid loss (e.g., through sweating, vomiting, diarrhea), and certain medical conditions.
What is hypotonic hydration, and what are its consequences?
Hypotonic hydration occurs when excess water is ingested, diluting body fluids and causing an imbalance. Consequences include cells swelling, which can lead to symptoms such as headache, nausea, and in severe cases, seizures or coma.
Briefly, what is edema?
Edema is the accumulation of excess fluid in the interstitial spaces of tissues, leading to swelling.
How do the kidneys regulate blood pH?
The kidneys regulate blood pH by excreting hydrogen ions (H+) and reabsorbing bicarbonate (HCO3-), which helps maintain the acid-base balance of the blood.
What is intracellular fluid, and where is it found?
Intracellular fluid is the fluid contained within the cells and is sometimes referred to as cytosol.
What is extracellular fluid, and what does it include?
Extracellular fluid is the fluid outside the cells and includes interstitial fluid and plasma.
What is interstitial fluid, and where is it located?
Interstitial fluid surrounds the cells and is located within tissues, being in direct contact with the cells.
What is plasma, and what percentage of total body water does it make up?
Plasma is the fluid component of blood, making up about 8% of total body water.
What percentage of total body water does extracellular fluid constitute?
Extracellular fluid constitutes about 40% of total body water.
What are some examples of small fluid compartments in the body?
Examples include lymph, cerebrospinal fluid, ocular humors, synovial fluid in joints, serous fluids in various cavities, and gastrointestinal secretions.
What are electrolytes, and how do they differ from non-electrolytes?
Electrolytes are substances that dissociate into ions in solution, such as sodium chloride. Non-electrolytes remain intact in solution, like glucose and urea.
Why do electrolytes have greater osmotic power compared to non-electrolytes?
Electrolytes have greater osmotic power because they dissociate into multiple particles in solution, affecting water movement more significantly.
How does osmotic pressure influence fluid movement between compartments?
Osmotic pressure causes water to move across membranes from areas of lower solute concentration to areas of higher solute concentration.
What role do hydrostatic pressures play in fluid movement?
Hydrostatic pressures push fluid out of capillaries into the interstitial space, influencing fluid distribution between compartments.
How are fluid movements regulated between compartments?
Fluid movements are regulated by osmotic and hydrostatic pressures, with membranes being freely permeable to water but less so to solutes.
What is the role of endothelial cells in capillary fluid movement?
Endothelial cells in capillaries facilitate fluid movement across capillary walls.
How does net water movement typically occur between fluid compartments?
Net water movement typically occurs in all directions, facilitating the exchange of gases, nutrients, and waste products.
What must occur for fluids to reach the intracellular compartment?
Fluids must pass through the plasma and interstitial fluid before reaching the intracellular compartment.
How does the body maintain osmolarity across fluid compartments?
The body maintains osmolarity by balancing solute concentrations across fluid compartments, despite different solute types.
What happens when there are significant changes in solute concentration?
Significant changes in solute concentration can cause deviations from equilibrium, leading to compensatory fluid shifts between compartments.
Why is homeostasis of body fluids and electrolytes crucial for cell function?
Homeostasis is crucial because it ensures proper cell function by maintaining the necessary water balance for chemical reactions and cellular activities.
What are the two major tasks for maintaining body fluid balance?
The two major tasks are maintaining intracellular fluid balance and maintaining plasma water balance.
Why is maintaining intracellular fluid balance important?
Maintaining intracellular fluid balance is essential for ensuring that cells have adequate water for proper functioning and chemical reactions.
What does maintaining plasma water balance ensure?
Maintaining plasma water balance ensures that body tissues are properly perfused, which is necessary for adequate oxygen and nutrient delivery and waste removal.
How is fluid balance maintained in the body?
Fluid balance is maintained by ensuring that water intake equals water output and by regulating solute concentrations and water losses.
Why are infants and the elderly particularly vulnerable to changes in water balance?
Infants and the elderly are more vulnerable due to their higher susceptibility to rapid changes in fluid balance and less efficient regulatory mechanisms.
What are insensible losses?
Insensible losses are water losses through breathing, skin, and the digestive tract, which often go unnoticed.
What are obligatory losses?
Obligatory losses are the required water loss through the kidneys needed to excrete waste.
What are the primary sources of water intake?
Water intake comes from fluids (60%), food (30%), and cellular metabolism (10%).
What are the primary routes of water output?
Water output occurs via urine (60%), insensible losses (28%), sweat (8%), and the digestive tract (4%).
How do baroreceptors contribute to fluid balance?
Baroreceptors detect changes in blood volume and help regulate fluid balance by influencing fluid intake and output.
What role do osmoreceptors play in fluid balance?
Osmoreceptors in the hypothalamus detect changes in osmolarity and help regulate fluid balance by triggering thirst or adjusting fluid excretion.
How is thirst regulated?
Thirst is regulated by the hypothalamus and is stimulated by a 1-2% change in osmolarity or a 5-10% change in plasma volume.
What inhibits the thirst mechanism?
Thirst is inhibited by the moistening of mucosa, stretch receptors in the stomach and small intestine, and a decrease in osmolarity.
What happens under isotonic conditions between fluid compartments?
Under isotonic conditions, intracellular fluid and extracellular fluid have equal solute concentrations, resulting in no net water movement.
What occurs with low water intake or excessive sweating?
With low water intake or excessive sweating, plasma osmotic pressure increases, making the plasma hypertonic compared to the cytosol, leading to water loss from cells.
What happens with high water intake?
With high water intake, plasma hydrostatic pressure increases, making the plasma hypotonic compared to the cytosol, causing water to move into cells until pressures are balanced.
What occurs if extracellular fluid is hypertonic?
If extracellular fluid is hypertonic, water moves from cells to the extracellular fluid.
What happens if extracellular fluid is hypotonic?
If extracellular fluid is hypotonic, water moves from the extracellular fluid into cells.
How do homeostatic mechanisms work to maintain fluid balance?
Homeostatic mechanisms regulate fluid balance by adjusting water intake and output and managing solute concentrations to maintain equilibrium.
What is the primary function of Antidiuretic Hormone (ADH)?
ADH primarily reduces water loss by stimulating water conservation in the kidneys.
Where is ADH produced and released from?
ADH is produced by the hypothalamus and released from the posterior pituitary.
What stimulates the release of ADH?
ADH release is stimulated by high sodium concentrations in extracellular fluid, changes in extracellular fluid detected by osmoreceptors, and large changes in blood or plasma volume detected by baroreceptors.
What effect does high ADH levels have on urine?
High ADH levels result in smaller volumes of concentrated urine.
What effect does low ADH levels have on urine?
Low ADH levels result in larger volumes of dilute urine.
What is the role of aldosterone in the body?
Aldosterone regulates sodium balance by increasing sodium and water reabsorption at the nephron, which raises extracellular fluid volume, blood volume, and blood pressure.
Which hormone stimulates aldosterone secretion?
Aldosterone secretion is stimulated by angiotensin II and elevated potassium levels in extracellular fluid.
What is the Renin-Angiotensin-Aldosterone System (RAAS)?
RAAS is a hormone system that regulates blood volume and blood pressure by affecting sodium and water reabsorption.
How does aldosterone affect potassium levels?
Aldosterone increases sodium reabsorption and promotes potassium secretion to maintain electrolyte balance.
What causes dehydration in the body?
Dehydration occurs when water output exceeds intake, leading to excessive loss of extracellular fluid.
Name a few causes of dehydration.
Causes include hemorrhage, severe burns, severe vomiting and diarrhea, profuse sweating with low water intake, and endocrine disturbances.
What is Diabetes Insipidus and how does it relate to ADH?
Diabetes Insipidus is a condition where inadequate ADH secretion leads to excessive water loss in urine.
How does uncontrolled Diabetes Mellitus contribute to dehydration?
Uncontrolled Diabetes Mellitus leads to high blood glucose levels, causing osmotic diuresis where water remains in the filtrate, resulting in large urine output and dehydration.
How does the body respond to severe dehydration and hypertonic hydration?
The body’s mechanisms work to counteract severe dehydration and hypertonic hydration, striving to maintain homeostasis by regulating fluid and electrolyte balance.
What is dehydration characterized by?
Dehydration is characterized by a loss of water from the extracellular fluid, with water loss typically exceeding sodium ion loss.
What happens to plasma osmolarity during dehydration?
Plasma osmolarity increases due to elevated solute concentration resulting from water loss.
What is hypernatremia and how does it relate to dehydration?
Hypernatremia refers to a higher sodium concentration in the extracellular fluid due to water loss making sodium more concentrated, even though sodium levels themselves haven’t increased.
What effect does dehydration have on cells?
Dehydration causes water to move from intracellular fluid to extracellular fluid via osmosis, leading to cell shrinkage (crenation) and impaired cell function.
Name two signs of dehydration.
Signs of dehydration include dry mucus membranes and decreased urine output (oliguria).
What is the role of the thirst center in dehydration?
The thirst center is activated by increased plasma osmolarity, stimulating thirst to encourage water intake.
What can prolonged dehydration lead to?
Prolonged dehydration can lead to hypovolemia (decreased circulating blood volume), reduced blood pressure, confusion, disorientation, and potentially hypovolemic shock.
How does the body compensate for low blood volume and pressure during dehydration?
The body activates the Renin-Angiotensin-Aldosterone System (RAAS), increasing aldosterone secretion to reabsorb sodium and water, and stimulating ADH secretion to promote water reabsorption in the kidneys.
What is hypotonic hydration?
Hypotonic hydration, or water intoxication, occurs when water intake exceeds output, leading to an excess of water in the extracellular fluid.
What happens to ADH levels during hypotonic hydration?
ADH levels are typically low during hypotonic hydration, resulting in increased urine output to prevent excess fluid accumulation.
What are the effects of hypotonic hydration on extracellular fluid osmolarity?
Excessive water lowers extracellular fluid osmolarity, causing hyponatremia (low sodium levels).
How does hypotonic hydration affect cells?
Excessive water in hypotonic hydration causes water to move from extracellular to intracellular fluid, leading to cell swelling (lysis) and potentially cell death.
What are some initial symptoms of hypotonic hydration?
Initial symptoms include nausea, vomiting, and muscle cramps.
What serious symptoms can progress from hypotonic hydration?
Serious symptoms can include disorientation, convulsions, coma, and even death due to cerebral edema (swelling of brain cells) and possible brain cell death.
Is hypotonic hydration common and what usually causes it?
Hypotonic hydration is rare and usually occurs due to renal insufficiency or extremely rapid water ingestion. Normal daily fluid intake (2-3 liters) in a healthy individual is generally safe.
What is edema?
Edema is an abnormal accumulation of fluid in the interstitial space, causing swelling of tissues.
What does the presence of edema typically indicate?
Edema often indicates an underlying disease or insufficiency, as it is not typically seen in healthy individuals.
What causes increased capillary hydrostatic pressure?
Increased capillary hydrostatic pressure, which pushes more fluid into the interstitial space, can be caused by conditions like heart failure or lymphatic obstruction.
How does increased capillary permeability contribute to edema?
Increased capillary permeability allows more fluid to escape into the interstitial space, often seen in infections where capillaries become more permeable.
What is the effect of decreased colloid osmotic pressure on fluid distribution?
Decreased colloid osmotic pressure reduces the ability to pull fluid back into the capillaries, leading to fluid accumulation in the interstitial space.
What conditions can lead to decreased colloid osmotic pressure?
Conditions such as protein malnutrition, liver disease, or kidney disease can result in decreased colloid osmotic pressure.
What are some effects of edema on the body?
Edema causes swelling of tissues, impairs tissue function by increasing the distance for oxygen and nutrient delivery, and can compromise cardiovascular function by decreasing circulating blood volume.
Where might edema typically appear in the body?
Edema may appear in the feet, ankles, or around the eyes.
How can severe edema affect cardiovascular function?
Severe edema can decrease circulating blood volume, affecting blood pressure and cardiovascular efficiency, leading to decreased tissue perfusion.
What is lymphedema?
Lymphedema is the accumulation of interstitial fluid due to surgically removed or blocked lymph glands, often seen after cancer treatments such as breast cancer surgery where lymph nodes are removed.
How can lymphedema be managed?
Lymphedema can be managed by wearing elasticized bandages and avoiding blood pressure measurements on the affected limb.
What does pH measure?
pH measures the acidity or alkalinity of a solution based on hydrogen ion concentration.
How do acids and bases affect pH?
Acids release hydrogen ions, increasing acidity, while bases bind hydrogen ions, decreasing acidity.
What is the normal pH range for body fluids?
The normal pH range for body fluids is between 7.35 and 7.45.
Why is it important to regulate pH?
Maintaining the pH range is crucial for cell function and biochemical reactions. Extreme pH levels can denature proteins and disrupt cellular processes.
What are the normal pH levels for arterial blood, venous blood, and intracellular fluid?
Arterial blood: ~7.4
Venous blood and interstitial fluid: ~7.35
Intracellular fluid: ~7
What pH levels are considered acidosis and alkalosis?
Acidosis: pH below 7.35
Alkalosis: pH above 7.45
What are the sources of hydrogen ions in the body?
Sources include metabolic processes (e.g., cellular respiration) and acidic substances from food and drink.
How are hydrogen ions removed from the body?
Hydrogen ions are removed via urine and by expelling carbon dioxide through the lungs.
What are the three mechanisms for pH regulation?
Chemical buffer systems
Respiratory regulation
Renal mechanism
How do chemical buffer systems function?
Buffers minimize changes in pH by binding or releasing hydrogen ions. They act quickly to stabilize pH.
What happens if pH drops in the buffer system?
Buffers bind hydrogen ions to reduce acidity and stabilize the pH.
What happens if pH rises in the buffer system?
Buffers release hydrogen ions to increase acidity and stabilize the pH.
What is the function of the Carbonic Acid-Bicarbonate Buffer System?
If pH drops: Bicarbonate binds with hydrogen ions to form carbonic acid, reducing free hydrogen ions and decreasing acidity.
If pH rises: Carbonic acid dissociates into bicarbonate and hydrogen ions, increasing hydrogen ions and acidity.
Why is the Carbonic Acid-Bicarbonate Buffer System crucial?
It helps maintain extracellular fluid pH by managing hydrogen ion concentrations without adding or removing ions from the solution.
What role does the respiratory system play in pH regulation?
The respiratory system helps regulate pH by controlling carbon dioxide (CO₂) levels in the blood.
How is CO₂ transported in the blood and eliminated?
CO₂ is mostly transported as bicarbonate ions in the blood plasma. At the respiratory membrane, bicarbonate is converted back to CO₂ for elimination through the lungs.
How does increased CO₂ affect blood pH?
Increased CO₂ leads to higher hydrogen ion levels, increasing acidity and lowering blood pH.
What happens to blood pH when the respiratory rate increases?
An increased respiratory rate removes excess CO₂, reducing hydrogen ion levels and restoring pH to its normal range.
What is the renal mechanism for pH regulation?
The renal mechanism regulates pH by removing or conserving acidic components through the kidneys, and by reabsorbing or excreting bicarbonate.
How do the kidneys respond if blood pH drops (becomes more acidic)?
The kidneys secrete excess hydrogen ions, reabsorb more bicarbonate, and generate additional bicarbonate to act as an alkaline reserve.
How do the kidneys respond if blood pH rises (becomes more alkaline)?
The kidneys absorb more hydrogen ions and secrete bicarbonate into the filtrate, which is then excreted in urine.
What are the absolute pH limits for blood?
The absolute limits for blood pH are 6.8 to 7.8. Anything outside this range is incompatible with life.
What is the normal range for blood pH?
The normal range for blood pH is around 7.4.
What is acidosis and what does it indicate?
Acidosis is a condition where plasma pH is less than 7.35, indicating an increase in hydrogen ion concentration.
What is alkalosis and what does it indicate?
Alkalosis is a condition where plasma pH is above 7.45, indicating a decrease in hydrogen ion concentration.
What causes respiratory acidosis?
Respiratory acidosis is caused by hypoventilation, leading to CO₂ retention and increased acidity. Conditions like pneumonia, cystic fibrosis, and emphysema can cause this.
What is metabolic acidosis and what causes it?
Metabolic acidosis is caused by excess fixed acids or loss of bicarbonate ions, seen in conditions like renal disease, excessive alcohol consumption, lactic acid production, and persistent diarrhea.
What causes respiratory alkalosis?
Respiratory alkalosis is caused by hyperventilation, often due to stress or pain, leading to reduced CO₂ and increased pH.
What causes metabolic alkalosis?
Metabolic alkalosis is caused by excess bases or loss of acids, seen in vomiting, antacid overdose, constipation, or excessive diuresis.
How do chemical buffers, the lungs, and kidneys each contribute to pH balance?
Chemical buffers act immediately to minimize pH changes.
Lungs regulate rapidly by eliminating CO₂.
Kidneys are slower but most effective in long-term pH regulation by removing acids and adding bicarbonate.
Which of the following is NOT a main body fluid compartment?
A) Intracellular fluid
B) Extracellular fluid
C) Interstitial fluid
D) Cerebrospinal fluid
D) Cerebrospinal fluid
How is the balance of sodium and potassium primarily maintained in the blood?
A) Through the digestive system
B) By the kidneys and hormonal regulation
C) By the liver
D) Through dietary intake alone
B) By the kidneys and hormonal regulation
Which hormone primarily regulates sodium levels in the body?
A) Antidiuretic Hormone (ADH)
B) Aldosterone
C) Insulin
D) Cortisol
B) Aldosterone
What is the primary function of Antidiuretic Hormone (ADH)?
A) Increase sodium reabsorption
B) Increase water reabsorption
C) Increase potassium excretion
D) Decrease blood volume
B) Increase water reabsorption
Which compartment contains the majority of the body’s fluid?
A) Extracellular fluid
B) Intracellular fluid
C) Interstitial fluid
D) Plasma
B) Intracellular fluid
What is dehydration?
A) An excess of water in the body
B) A condition where water loss exceeds intake
C) An abnormal accumulation of fluid in tissues
D) An increase in blood sodium levels
B) A condition where water loss exceeds intake
Which of the following is a common cause of dehydration?
A) Overhydration
B) Severe burns
C) Excessive sodium intake
D) Hypotonic hydration
B) Severe burns
What is hypotonic hydration?
A) Excessive water intake leading to diluted blood sodium levels
B) Loss of water exceeding sodium loss
C) Accumulation of fluid in the interstitial space
D) Reduced water intake
A) Excessive water intake leading to diluted blood sodium levels
Which condition is characterized by swelling due to fluid accumulation in the interstitial space?
A) Hypovolemia
B) Dehydration
C) Edema
D) Hypernatremia
C) Edema
What causes edema due to increased capillary hydrostatic pressure?
A) High levels of blood proteins
B) Low levels of interstitial fluid
C) Elevated pressure pushing fluid into interstitial spaces
D) Decreased capillary permeability
C) Elevated pressure pushing fluid into interstitial spaces
What is the role of the kidneys in pH regulation?
A) Adjusting carbon dioxide levels
B) Secreting or conserving hydrogen ions and bicarbonate
C) Increasing blood sodium levels
D) Regulating blood glucose levels
B) Secreting or conserving hydrogen ions and bicarbonate
How does the respiratory system affect blood pH?
A) By regulating blood glucose levels
B) By controlling CO₂ levels through changes in breathing rate
C) By absorbing excess hydrogen ions
D) By increasing blood volume
B) By controlling CO₂ levels through changes in breathing rate
What happens when the kidneys detect a drop in blood pH (more acidic)?
A) They reabsorb bicarbonate and excrete hydrogen ions
B) They excrete bicarbonate and absorb hydrogen ions
C) They increase CO₂ levels in the blood
D) They reduce sodium reabsorption
A) They reabsorb bicarbonate and excrete hydrogen ions
What is the normal range for blood pH?
A) 6.8 to 7.8
B) 7.35 to 7.45
C) 6.0 to 7.0
D) 7.0 to 8.0
B) 7.35 to 7.45
What is respiratory alkalosis?
A) High CO₂ levels causing low pH
B) High bicarbonate levels causing high pH
C) Low CO₂ levels causing high pH
D) Low bicarbonate levels causing low pH
C) Low CO₂ levels causing high pH
What is a common cause of metabolic acidosis?
A) Excessive vomiting
B) Excess bases in the diet
C) Excess fixed acids or loss of bicarbonate
D) Hyperventilation
C) Excess fixed acids or loss of bicarbonate
Which buffer system helps maintain extracellular fluid pH by managing hydrogen ion concentrations?
A) Phosphate Buffer System
B) Protein Buffer System
C) Carbonic Acid-Bicarbonate Buffer System
D) Hemoglobin Buffer System
C) Carbonic Acid-Bicarbonate Buffer System
What happens in the body during hypovolemic shock due to severe dehydration?
A) Increased blood volume
B) Decreased blood pressure and reduced tissue perfusion
C) Increased urine output
D) Decreased CO₂ levels
B) Decreased blood pressure and reduced tissue perfusion
In hypotonic hydration, what happens to the extracellular fluid osmolarity?
A) It increases
B) It decreases
C) It remains unchanged
D) It fluctuates
B) It decreases
What is the main function of chemical buffers in pH regulation?
A) To remove hydrogen ions from the blood
B) To bind or release hydrogen ions to minimize pH changes
C) To increase CO₂ levels in the blood
D) To alter kidney function
B) To bind or release hydrogen ions to minimize pH changes
True or false
The extracellular fluid compartment makes up the largest fluid compartment of the body.
False
List the fluid compartments of the body and state their volumes.
Intracellular fluid (ICF) 60%
Extracellular fluid (ECF) 40% = Plasma 3L + Interstitial fluid (ISF) 13L
Why is water essential to life?
Required for metabolic reactions & dissolves solutes
What is the predominate cation of the ECF & ICF?
ECF = Na+
ICF = K+
True or false
The hypothalamic thirst centre is stimulated by a 5–10% drop in plasma volume.
True: ↓ ECF (plasma/blood) volume = ↓BP
stimulates baroreceptors
Activates RAAS 🡪 leads to the production of Angiotensin II
Define oedema.
Abnormal accumulation of fluid in the ISF
List three causes of oedema.
↑ capillary hydrostatic pressure
↓ capillary colloid osmotic pressure
↑capillary permeability
Why can oedema impair tissue functioning?
↑ distance for O2 & nutrients to diffuse between blood & cells
In addition to a decrease in ECF volume, what other stimulus triggers thirst?
↑ ECF osmolarity (Na+ concentration)
activates osmoreceptors
decreases salivation = dry mouth
What feedback mechanism operate to inhibit thirst?
Moistening of the mouth/throat mucosa
Stimulation of stretch receptors stomach/intestines
↓ ECF osmolarity to normal levels
Normal constituents of urine include:
a) urea and blood
b) water and glucose
c) creatinine and glucose
d) urea and creatinine
Normal constituents of urine include:
a) urea and blood
b) water and glucose
c) creatinine and glucose
d) urea and creatinine
Glomerular filtration:
a) occurs in the renal corpuscle
b) involves active transport
c) moves large substances through the filtration membrane
d) moves water back into blood
Glomerular filtration:
a) occurs in the renal corpuscle
b) involves active transport
c) moves large substances through the filtration membrane
d) moves water back into blood
Tubular secretion:
a) transports useful substances back into blood
b) occurs at the renal papillae
c) removes drugs from the blood
d) requires the hormone aldosterone
Tubular secretion:
a) transports useful substances back into blood
b) occurs at the renal papillae
c) removes drugs from the blood
d) requires the hormone aldosterone
Which of the following is NOT a function of the kidneys?
a) Gluconeogenesis
b) Activation of vitamin D
c) Stimulation of red blood cell production
d) Production of ADH
Which of the following is NOT a function of the kidneys?
a) Gluconeogenesis
b) Activation of vitamin D
c) Stimulation of red blood cell production
d) Production of ADH
Glomerular filtration rate (GFR) is the amount of:
a) blood filtered per minute
b) filtrate formed per minute
c) urine formed per minute
d) solutes reabsorbed per minute
Glomerular filtration rate (GFR) is the amount of:
a) blood filtered per minute
b) filtrate formed per minute
c) urine formed per minute
d) solutes reabsorbed per minute
High blood pressure activates RAAS resulting in stimulation of adrenal glands to secrete aldosterone
True or False
False
Antidiuretic hormone (ADH) is released:
a) from anterior pituitary
b) when ECF sodium concentration is high
c) when plasma osmolarity is low
d) from adrenal medulla
Antidiuretic hormone (ADH) is released:
a) from anterior pituitary
b) when ECF sodium concentration is high
c) when plasma osmolarity is low
d) from adrenal medulla
Thirst is inhibited by stretch receptors
True or False
True
Sodium is the predominant ion of the ICF
True or False
False (Potassium is the predominant ion of the ICF)
In dehydration there will be:
a) swelling of cells
b) hyponatraemia
c) oliguria
d) decreased thirst
In dehydration there will be:
a) swelling of cells
b) hyponatraemia
c) oliguria
d) decreased thirst
In hypotonic hydration there is:
a) too much water in the ECF
b) too much sodium in the ECF
c) crenation of cells
d) hypernatraemia
In hypotonic hydration there is:
a) too much water in the ECF
b) too much sodium in the ECF
c) crenation of cells
d) hypernatraemia
In oedema there is an abnormal accumulation of fluid in the interstitial space.
True or False
True
When working to stabilise an acidic blood pH the renal system will:
a) secrete Na+
b) secrete HCO3- & H+
c) reabsorb H+ & secrete Na+
d) reabsorb HCO3- & secrete H+
When working to stabilise an acidic blood pH the renal system will:
a) secrete Na+
b) secrete HCO3- & H+
c) reabsorb H+ & secrete Na+
d) reabsorb HCO3- & secrete H+
Hypoventilation may cause respiratory acidosis.
True or False
True
Chemical buffers serve to bind hydrogen ions if pH drops(acidic)
True or false
True
What is a chemical buffer?
A substance or solution that minimises changes in pH by binding or releasing H+ ions
How do chemical buffers assist with maintenance of pH (acid/base) balance in the plasma?
Chemical buffers are rapid and can temporarily tie up or release H+ ions.
Hyponatremia (low Na+ ions in ECF) is seen in dehydration.
True or false
False
Define dehydration. What causes it?
Water output > water input
What happens to osmolarity during dehydration?
↑ osmolarity
What happens to fluid movement during dehydration?
H2O will move from the ICF to the ECF
What happens to cells during dehydration? Does this happen in every case of dehydration?
Crenate
No 🡪 Haemorrhage – whole blood lost, so water & solutes lost at the same rate = no change in osmolarity
Oedema is a fluid distribution problem where there is an abnormal accumulation of fluid in the intracellular compartment.
True or false.
False
Explain the cause of oedema. Why might tissue functioning be impaired in oedema?
Cause of oedema:
Oedema occurs due to an abnormal accumulation of fluid in the interstitial spaces between cells. It can result from various factors, such as increased capillary pressure (e.g., in heart failure), reduced plasma protein levels (e.g., in liver disease or malnutrition), increased capillary permeability (e.g., in inflammation), or impaired lymphatic drainage (e.g., due to blockage or removal of lymph nodes).
Why tissue functioning might be impaired in oedema:
Excess fluid in the interstitial spaces can compress surrounding tissues and capillaries, reducing the delivery of oxygen and nutrients. This impairs cellular function, slows wound healing, and can lead to tissue damage. The swelling can also disrupt normal tissue architecture and interfere with cellular processes.
Trudy is a 78yr old woman with progressively worsening osteoarthritis. This disorder has affected many joints within her body, including those of the thoracic cavity, and is causing her pain on inspiration, making breathing difficult.
a. How will Trudy’s condition affect her blood pH?
Hypoventilation = ↑ blood PCO2 🡪 reaction pushed to the RHS = ↑ H+ ions = ↓pH
Trudy is a 78yr old woman with progressively worsening osteoarthritis. This disorder has affected many joints within her body, including those of the thoracic cavity, and is causing her pain on inspiration, making breathing difficult.
b. What happens to H+ ions should excess H+ ions produced?
Secreted from the blood into the filtrate and excreted by the kidneys in urine – thus urine will contain more H+ ions
Joanne, a diabetic patient, is at the emergency department with acidosis due to the production of ketones.
a. What mechanisms will be working to attempt to correct Joanne’s acidosis?
- Carbonic-acid bicarbonate buffer system (seconds)
- Respiratory System (1-3 minutes)
- Kidneys (hours-days)
Joanne, a diabetic patient, is at the emergency department with acidosis due to the production of ketones.
b. What respiratory symptom would you expect Joanne to exhibit and why?
Hyperventilation. ↑ H+ ions leads to ↑ CO2 will stimulate brain stem respiratory
George is running a marathon on a hot day and perspires heavily. Throughout the marathon, George does not drink enough water and becomes dehydrated, leading to hypernatremia (high plasma sodium levels). Consequently, he shows signs of confusion and disorientation.
1. What has caused George’s hypernatremia?
Dehydration 🡪Water output > water input
Hypernatremia 🡪 Water loss > solute loss
George is running a marathon on a hot day and perspires heavily. Throughout the marathon, George does not drink enough water and becomes dehydrated, leading to hypernatremia (high plasma sodium levels). Consequently, he shows signs of confusion and disorientation.
2. How will George’s condition affect his ECF osmolarity and blood volume?
↓ ECF (plasma) volume, ↑ ECF osmolarity
George is running a marathon on a hot day and perspires heavily. Throughout the marathon, George does not drink enough water and becomes dehydrated, leading to hypernatremia (high plasma sodium levels). Consequently, he shows signs of confusion and disorientation.
3. Why does George exhibit signs of confusion and disorientation?
↑ ECF Osmolarity 🡪 H2O shifts from the ICF to the ECF 🡪 cells crenate = neural dysfunction = confusion & disorientation
George is running a marathon on a hot day and perspires heavily. Throughout the marathon, George does not drink enough water and becomes dehydrated, leading to hypernatremia (high plasma sodium levels). Consequently, he shows signs of confusion and disorientation.
4. How will George’s condition affect his thirst?
Stimulates the thirst mechanism = ↑ thirst
What is the equation that defines the carbonic-acid bicarbonate buffer system.
CO2 + H2O ⇔ H2CO3 ⇔ H+ + HCO3-
George is running a marathon on a hot day and perspires heavily. Throughout the marathon, George does not drink enough water and becomes dehydrated, leading to hypernatremia (high plasma sodium levels). Consequently, he shows signs of confusion and disorientation.
6. Explain the negative feedback mechanism that operates to control thirst.
moistening of the mouth and throat mucosa
stimulation of stretch receptors in the stomach & small intestines
🡫 ECF osmolarity to normal levels
Leanne suffers from a bout of food poisoning after visiting the new local restaurant. Leanne has diarrhoea and has been vomiting for hours. Leanne has been unable to eat any food and to replenish lost fluids, Leanne drinks only water. Eventually, the vomiting and diarrhoea subside but Leanne continues to drink only water.
1. As Leanne continues to drink only water what condition is she at risk of developing?
Hypotonic hydration
Leanne suffers from a bout of food poisoning after visiting the new local restaurant. Leanne has diarrhoea and has been vomiting for hours. Leanne has been unable to eat any food and to replenish lost fluids, Leanne drinks only water. Eventually, the vomiting and diarrhoea subside but Leanne continues to drink only water.
2. How will this condition affect her ECF osmolarity and volume?
↑ ECF (plasma) volume, ↓ ECF osmolarity
Leanne suffers from a bout of food poisoning after visiting the new local restaurant. Leanne has diarrhoea and has been vomiting for hours. Leanne has been unable to eat any food and to replenish lost fluids, Leanne drinks only water. Eventually, the vomiting and diarrhoea subside but Leanne continues to drink only water.
3. How will this affect the ICF volume and body cells?
↓ ECF Osmolarity 🡪 H2O shifts from the ECF to the ICF 🡪 ↑ ICF volume 🡪 cells swell/lyse🡪 impairs/destroys cell function
List three causes of oedema.
↑ capillary hydrostatic pressure
↓ capillary colloid osmotic pressure
↑capillary permeability
Why can oedema impair tissue functioning?
↑ distance for O2 & nutrients to diffuse between blood & cells
What contribution can HCO3- make to pH (acid/base) balance in the plasma?
Works as a buffer. Ties up H+ ions when pH is low
Are there other ways in which the kidneys act to balance pH in the plasma?
Tubular reabsorption and secretion at the kidneys is able to modify retention or removal of H+ ions.
The kidneys are also able to conserve and generate HCO3- or excrete HCO3-
How long does the renal mechanism take to have an effect?
The renal mechanism is the most potent mechanism for balancing pH, but takes several hours (even days) for a full response.
Chemical buffer system: rapid (within seconds) (include carbonic acid-bicarbonate buffer system, phosphate buffer and protein buffer system)
Respiratory system: acts within minutes
Renal system: acts within hours to days
