Fluid- electrolyte and acid base balance

Sodium

The most prevalent electrolyte in the extracellular fluid is __________.

slightly alkaline

Normal arterial blood pH is __________.

A rise in plasma osmolality ADH results in increased water reabsorption.

A major stimulus for the release of antidiuretic hormone is __________.

hydrogen Acidosis refers to high H+ concentration.

Acidosis results in increasing levels of what ion?

Hypotonic extracellular fluid Angiotension II would stimulate the hypothalmic thirst center

All of the following factors would stimulate the hypothalamic thirst center EXCEPT __________.

Production of large amounts of urine If the plasma osmolalilty were to increase, ADH would be released

All of the following would occur if there were an increase in plasma osmolality EXCEPT __________.

Kidneys; decrease

Antidiuretic hormone (ADH) acts on the __________ to __________ water excretion.

7.0 and 7.35

Any arterial pH between __________ is considered physiological acidosis.

One hour

Diuresis peaks __________ after drinking water.

Interstitial space

Edema is the accumulation of fluid in the __________.

Salts

Electrolyte balance in the body usually refers to the balance of __________.

Aldosterone

Estrogens are chemically similar to __________ and are therefore associated with water retention.

Respiratory alkalosis

Hyperventilation can lead to

The inefficiency of infant kidneys The kidneys are immature at birth; they are approximately half as proficient at concentrating urine as mature kidneys. Infant kidneys are also inefficient in ridding the body of acids.

Infants are more likely to experience problems regulating acid-base balance because of several factors, including __________.

Kidneys Water output occurs by several routes. Water that vaporizes out of the lungs in expired air or diffuses directly through the skin is called insensible water loss. Some water is also lost in perspiration and feces. The rest, about 60% of the total water output, is excreted by the kidneys in urine.

Most water is excreted via the __________.

Generating new HCO3- The most important renal mechanism for regulating acid-base balance of the blood involves controlling blood bicarbonate (HCO3-) levels. This is achieved by conserving or generating HCO3- and excreting HCO3-.

One way the kidneys maintain HCO3- balance is by __________.

enhances release of calcium from bone PTH activates osteoclasts, which break down the bone matrix, releasing calcium.

Parathyroid hormone __________.

Na+ transport

Renal acid-base control mechanisms are coupled to __________.

Respiratory acidosis

Someone who is suffocating would develop __________.

hyponatremia Hypo- means low, and natrium is Latin for sodium.

The condition in which sodium levels are too low is referred to as __________.

Intracellular fluid

The largest percentage of body water is located in what compartment?

Urine Urine accounts for roughly 60% of the body's water loss.

The major source of water loss from the body is __________.

False, it is sodium.

The most abundant cation in extracellular fluid is potassium.

Protein Most of the buffering power of body fluids resides in cells, and most of this reflects the buffering activity of intracellular proteins.

The most important buffer system in the intracellular fluid compartment (ICF) is the __________ buffer system.

Bicarbonate

The most important buffer system of extracellular fluid, such as plasma, is the __________ buffer system.

the concentration of K+ in the ECF

The most important factor that influences K+ secretion is __________.

Na+

The only cation exerting significant osmotic pressure in the ECF is __________.

Kidney

The only organ(s) of the body that can remove excess nonvolatile fixed acids is/are the __________.

False

True or false: Most fluid in the body is in the extracellular fluid (ECF) compartment

False Small amounts of acids enter the body via ingested foods. However, most H+ ions originate as metabolic by-products or end products. For example, the breakdown of phosphorus-containing proteins, the anaerobic breakdown of glucose, fat metabolism, and the loading and transport of CO2 in the blood all serve as sources of hydrogen ions in the body.

True or false: Most of the hydrogen ions in the body come from acidic substances in the foods we ingest.

False Parathyroid hormone (PTH) is released in response to low Ca2+ levels. PTH causes the release of Ca2+ from the bones, increases absorption of Ca2+ by the small intestine, and increases calcium reabsorption in the proximal convoluted tubule of the kidneys.

True or false: Parathyroid hormone (PTH) increases Ca2+ deposition in the bones.

Insensible water loss

Water lost through expired air is referred to as __________.

Potassium Potassium is the most abundant cation in the intracellular fluid and is required for essential metabolic activities, influencing the resting membrane potential and normal neuromuscular functioning.

What is the most abundant cation in intracellular fluid?

Bicarbonate buffer system

What is the primary buffer system for ECF?

Decreased sodium and water reabsorption ANP reduces blood pressure and blood volume by inhibiting nearly all events that promote vasoconstriction, sodium retention, and water retention.

When atrial natriuretic peptide is released by the heart because of increased blood pressure, it causes __________.

Aldosterone levels increase When the concentration of Na+ in the ECF decreases, there is an increase in the level of aldosterone, which causes facultative Na+ reabsorption.

When the concentration of Na+ in the ECF decreases, __________.

Hypoventilation

Which condition would cause a drop in pH?

The phosphate buffer system The bicarbonate buffer system is the primary buffer system for the ECF. Because the phosphate buffer system is present in low concentrations in the ECF (approximately one-sixth that of the bicarbonate buffer system), it is relatively unimportant for buffering blood plasma. However, it is a very effective buffer in urine and in ICF, where phosphate concentrations are usually higher.

Which of the following has the LEAST influence over the pH of blood plasma?

An infant An infants body is 73% or more water

Which of the following individuals would have the most body water?

Glucose

Which of the following is NOT an electrolyte?

Hypotonic hydration Hypotonic hydration causes hyponatremia (low concentration of Na+ in the extracellular fluid), leading to cell swelling.

Which of the following is associated with a swelling of cells?

Their inefficient kidneys At birth, the kidneys are inefficient; these infant kidneys do not concentrate urine or conserve water efficiently, putting infants at risk for dehydration. Vomiting, diarrhea, and a high rate of insensible water loss also increase the risk for dehydration.

Which of the following puts infants at increased risk for dehydration?

Adipose tissue

Which of the following tissues is the least hydrated?

Progesterone Atrial natriuretic peptide (ANP) and progesterone increase Na+ excretion. Progesterone appears to decrease NaCl reabsorption by blocking the effect aldosterone has on the renal tubules. Aldosterone is the key regulator of sodium reabsorption in the kidney. It encourages Na+ reabsorption. Estrogens, like aldosterone, encourage Na+ reabsorption. Glucocorticoids enhance tubular reabsorption of sodium. 8. Incorrect Parathyroid hormone (PTH) increases Ca2+ deposition in the bones. Your Answer: True Correct Answer: False Parathyroid hormone (PTH) is released in response to low Ca2+ levels. PTH causes the release of Ca2+ from the bones, increases absorption of Ca2+ by the small intestine, and increases calcium reabsorption in the proximal convoluted tubule of the kidneys. 9. Incorrect Most of the hydrogen ions in the body come from acidic substances in the foods we ingest. Your Answer: True Correct Answer: False Small amounts of acids enter the body via ingested foods. However, most H+ ions originate as metabolic by-products or end products. For example, the breakdown of phosphorus-containing proteins, the anaerobic breakdown of glucose, fat metabolism, and the loading and transport of CO2 in the blood all serve as sources of hydrogen ions in the body. 10. Incorrect The most important factor that influences K+ secretion is __________. Your Answer: water balance in the body Correct Answer: the concentration of K+ in the ECF The single most important factor that influences K+ secretion is the concentration of K+ in the ECF. 11. Incorrect Which of the following has the LEAST influence over the pH of blood plasma? Your Answer: the bicarbonate buffer system Correct Answer: the phosphate buffer system The bicarbonate buffer system is the primary buffer system for the ECF. Because the phosphate buffer system is present in low concentrations in the ECF (approximately one-sixth that of the bicarbonate buffer system), it is relatively unimportant for buffering blood plasma. However, it is a very effective buffer in urine and in ICF, where phosphate concentrations are usually higher. 12. Correct Hyperventilation can lead to __________. Your Answer: respiratory alkalosis 13. Incorrect One way the kidneys maintain HCO3- balance is by __________. Your Answer: reabsorbing H+ Correct Answer: generating new HCO3- The most important renal mechanism for regulating acid-base balance of the blood involves controlling blood bicarbonate (HCO3-) levels. This is achieved by conserving or generating HCO3- and excreting HCO3-. 14. Correct Someone who is suffocating would develop __________. Your Answer: respiratory acidosis 15. Incorrect Which of the following puts infants at increased risk for dehydration? Your Answer: their low surface area to volume ratio Correct Answer: their inefficient kidneys At birth, the kidneys are inefficient; these infant kidneys do not concentrate urine or conserve water efficiently, putting infants at risk for dehydration. Vomiting, diarrhea, and a high rate of insensible water loss also increase the risk for dehydration.

Which of the following would increase sodium excretion?

Weak acids only dissociate partially in solution Strong acids dissociate fully, and weak acids dissociate incompletely.

Which statement about acids is true?