A&P2 • Connect • Chapter24

false

true or false: obligatory water loss is observed only in well hydrated people.

false

true or false: respiratory loss decreases in cold weather.

buffer

________________ systems are composed of a weak acid and a weak base.

urine

_________________ excretion represents the major route of water loss.

balance

a person is in a state of fluid ________________ when daily gains and losses are equal. we typically gain and lose about 2,500 mL/day.

c) weak

an acid such as carbonic acid (H2CO3) that ionizes only slightly and keeps most hydrogen in a chemically bound form that does not affect pH, is classified as which type of acid? a) nucleic b) amino c) weak d) strong

b) calcitonin + d) calcitriol + e) PTH

calcium homeostasis is regulated by which hormones? select three from the list below. a) aldosterone b) calcitonin c) ADH d) calcitriol e) PTH

a) abnormal concentration such as in hypotonic hypovolemia + b) abnormal volume such as in hemorrhage + c) abnormal distribution such as in edema of the lower limbs

which are examples of a state of fluid imbalance? select all that apply. a) abnormal concentration such as in hypotonic hypovolemia b) abnormal volume such as in hemorrhage c) abnormal distribution such as in edema of the lower limbs d) abnormal oxygen transport such as in anemia

a) water in an apple + b) water in a baked potato and steak dinner + d) water in a glass of milk

which are examples of preformed water? select all that apply. a) water in an apple b) water in a baked potato and steak dinner c) water formed as a byproduct of dehydration synthesis reactions and aerobic respiration d) water in a glass of milk

b) distension of the stomach + c) cooling the mouth + d) moistening the mouth

which are fast-acting stimuli that cause a temporary, short-term inhibition of thirst? select all that apply. a) decreased blood osmolarity b) distension of the stomach c) cooling the mouth d) moistening the mouth

a) resists changes in pH

a buffer can be generally defined as a mechanism that does which of the following? a) resists changes in pH b) amplifies changes in pH c) provides energy for a cell d) catalyzes biological reactions

acidosis

a tissue fluid pH below 7.35 is defined as a state of __________________.

imbalance

the body is in a state of fluid ________________ if there is an abnormality of total volume, concentration, or distribution of fluid among the compartments.

a) aldosterone + b) antidiuretic hormone + c) natriuretic peptides

which regulate sodium homeostasis? select all that apply. a) aldosterone b) antidiuretic hormone c) natriuretic peptides d) calcitriol e) parathyroid hormone

a) dehydration raises blood osmolarity

which statement about dehydration is true? a) dehydration raises blood osmolarity b) dehydration raises blood volume c) dehydration increases blood pressure d) dehydration increases salivation

a) muscle spasms + e) convulsions

acidosis depresses the central nervous system and alkalosis makes the nervous system hyperexcitable. based on this, which of the following are possible symptoms of alkalosis? select all that apply. a) muscle spasms b) coma c) confusion d) disorientation e) convulsions

osmosis

if a local imbalance between the intracellular and extracellular fluid occurs, water movement called ________________ restores the balance. this depends on the relative concentration of solutes in each compartment.

b) volume excess

if the body has retained too much sodium and water, but the ECF remains isotonic, the person has which of the following? a) hypovolemia b) volume excess c) hypotonic hydration d) circulatory shock

b) aquaporins

in response to ADH release, collecting duct cells in the kidneys increase their expression of which of the following? a) albumin b) aquaporins c) prostacyclin d) prolactin

b) strong acid

HCl ionizes freely, gives up most of its hydrogen ions and can markedly lower the pH of a solution. because of this it is classified as which of the following? a) weak base b) strong acid c) weak acid d) strong base

b) volume excess

in which form of fluid imbalance is total body water elevated while osmolarity remains normal? a) dehydration (negative water balance) b) volume excess c) hypotonic hydration (positive water balance, water intoxication) d) hypovolemia (volume depletion)

d) CO2

the bicarbonate system works quite well because the lungs and kidneys constantly remove which of the following? this prevents equilibrium from being reached. a) Na+ b) carbonic acid c) ammonia d) CO2

a) weak base

as compared to hydroxide (OH), bicarbonate (HCO3) binds a relatively small amount of the available H and therefore has less of an effect on pH. because of this, bicarbonate is classified as which of the following? a) weak base b) strong base c) weak acid d) strong acid

a) participates in muscle contraction + b) participates in bone and tooth development + c) acts as a factor for blood clotting + d) acts as second messenger and activates exocytosis during neurotransmission

calcium does which of the following? select all that apply. a) participates in muscle contraction b) participates in bone and tooth development c) acts as a factor for blood clotting d) acts as second messenger and activates exocytosis during neurotransmission e) plays a major role in the maintenance of blood pH

b) cells actively pump out Ca2+ + c) cells often have a protein called calsequestrin, which binds the stored Ca2+ and keeps it chemically unreactive + d) cells sequester Ca2+ in the smooth ER and release it only when needed

cells maintain a very low intracellular calcium concentration to avoid crystallization of calcium phosphate. which mechanisms maintain intracellular calcium concentrations low? select all that apply. a) calcium binds to potassium or to sodium and becomes chemically inactive b) cells actively pump out Ca2+ c) cells often have a protein called calsequestrin, which binds the stored Ca2+ and keeps it chemically unreactive d) cells sequester Ca2+ in the smooth ER and release it only when it needed

a) sodium reabsorption

changes in urine volume are often linked to adjustments in which of the following? a) sodium reabsorption b) calcium excretion c) potassium reabsorption d) hydrogen ion excretion

a) loss of blood volume

fluid deficiency can cause serious effects. for example, circulatory shock may be caused by which of the following? a) loss of blood volume b) low blood osmolarity c) dehydration of brain cells d) water intoxication

osmoreceptors

fluid intake is governed by thirst and is regulated by a group of hypothalamic neurons called _________________, which respond to angiotension II and to rising osmolarity of the ECF.

d) reduced blood pressure

fluid intake is governed mainly by thirst. which of the following can make a person thirsty? a) decreased ADH production b) decreased plasma osmolarity c) distention of stomach and intestines d) reduced blood pressure

a) phosphates are more important in the renal tubules and ICF + b) the phosphate buffer system has a stronger buffering effect than an equal amount of bicarbonate buffer + c) the phosphate buffer system has a higher optimal pH

how does the phosphate buffer system differ from the bicarbonate buffer system? select all that apply. a) phosphates are more important in the renal tubules and ICF b) the phosphate buffer system has a stronger buffering effect than an equal amount of bicarbonate buffer c) the phosphate buffer system has a higher optimal pH d) phosphates are more concentrated in the ECF e) phosphates play a larger role in buffering the ECF

• metabolic acidosis = excess producing of organic acids (i.e. diabetes mellitus and starvation; hyperkalemia; chronic diarrhea; excessive alcohol consumption; aspirin; laxatives) • metabolic alkalosis = rare but can result from chronic vomiting; overuse of antacids; aldosterone hypersecretion • respiratory acidosis = hypoventilation; apnea • respiratory alkalosis = hyperventilation due to pain or emotions such as anxiety

match the pH disorder with its cause. metabolic acidosis - metabolic alkalosis - respiratory acidosis - respiratory alkalosis hypoventilation; apnea - hyperventilation due to pain or emotions such as anxiety - rare but can result from chronic vomiting; overuse of antacids; aldosterone hypersecretion - excess production of organic acids (i.e. diabetes mellitus and starvation; hyperkalemia; chronic diarrhea; excessive alcohol consumption; aspirin; laxatives)

d) bicarbonate, phosphate and protein

name the three important chemical buffer systems in the body. a) urinary and respiratory b) bicarbonate, phosphate and nitrate c) bicarbonate, nucleic acids and protein d) bicarbonate, phosphate and protein

insensible

output through the expired air and cutaneous transpiration (but not including fecal moisture, urine and sweat) is called ___________________ water loss because we are not usually conscious of it.

c) cardiac abnormalities

potassium imbalances are the most dangerous of all electrolyte imbalances. what is the most serious consequence of potassium imbalance? a) muscle weakness b) edema c) cardiac abnormalities d) nerve damage

b) fluid excess

pulmonary and cerebral edema are among the most serious effects of which of the following? a) dehydration b) fluid excess c) hypovolemia d) circulatory shock

1) urine 2) cutaneous transpiration 3) expired breath 4) feces 5) sweat (at an ambient temperature of 20ºC/68ºF)

rank the following routes of normal water loss from largest volume to smallest volume. • feces • urine • expired breath • cutaneous transpiration • sweat (at an ambient temperature of 20ºC/68ºF)

c) 30minutes

reduced blood osmolarity stops the osmoreceptor response and produces long-term thirst satiation. approximately how long after drinking will these long-term changes take effect? a) 5minutes b) 90minutes c) 30minutes d) 60minutes

b) because HCl is too strong of an acid and would drop the pH of the tubular fluid below the limiting pH

since there is so much chloride in the tubular fluid, why is H+ excreted as ammonium chloride (NH4Cl) and not simply excreted as hydrochloric acid (HCl)? a) because only ammonium chloride also helps to eliminate chloride b) because HCl is too strong of an acid and would drop the pH of the tubular fluid below the limiting pH c) because HCl is too weak of an acid and would not eliminate enough H+ d) because ammonium chloride is a base instead of an acid

pH

slight deviations from the body's normal __________________ range can shut down metabolic pathways as well as alter the structure and function of other macromolecules. buffer systems help to avoid this.

protein

the ________________ buffer system accounts for about three-quarters of all chemical buffering in the body fluids, especially in the ICF.

c) phosphate

the __________________ buffer system is a solution of H(PO4)2 and H2(PO4). a) protein b) bicarbonate c) phosphate

c) respiratory

the addition of CO2 to the body fluids raises H+ concentration and lowers pH, while the removal of CO2 has the opposite effect. this is the basis for the strong buffering capacity of which system? a) endocrine b) digestive c) respiratory d) urinary

b) amino side groups when H+ when pH falls + c) carboxyl side groups release H+ when pH begins to rise

the buffer ability of proteins is primarily due to which of the following? select all that apply. a) the ability of HPO4^3- to bind H when pH begins to rise b) amino side groups bind H+ when pH falls c) carboxyl side groups release H+ when pH begins to rise d) the formation of carbonic acid

hyperkalemia

the condition called __________________ is a dangerously high plasma potassium concentration greater than 5.5mEq/L.

strong

the hydroxide ion (OH-) is an example of a _________________ base, which has a great tendency to bind H+ and raise the pH.

carbonic

the most important buffer system in the blood is the bicarbonate buffer, which is a solution of __________________ acid and bicarbonate ions.

hypokalemia

the potassium imbalance known as __________________ is a plasma concentration of potassium less than 3.5mEq/L.

a) diabetes mellitus + c) profuse sweating + d) cold or hot weather + e) overuse of diuretics

the simplest cause of dehydration is a lack of drinking water. which of the following can also cause dehydration? select all that apply. a) diabetes mellitus b) hypersecretion of ADH c) profuse sweating d) cold or hot weather e) overuse of diuretics

• urine = 1500mL/day • feces = 200mL/day • sweat = 100mL/day • expired breath = 300mL/day • cutaneous transpiration = 400mL/day

the total water output per day in a resting adult is about 2500mL. match the route of water loss with its approximate normal volume. urine - feces - sweat - expired breath - cutaneous transpiration 100mL/day - 400mL/day - 200mL/day - 300mL/day - 1500mL/day

true

true or false: cold weather has a dehydrating effect on the human body.

false

true or false: dehydration affects the extracellular fluid exclusively.

false

true or false: during dehydration, the kidneys restore blood volume by the formation of metabolic water.

true

true or false: the only way to control water output significantly is through variations in urine volume.

1) H in blood reacts with HCO3- to form H2CO3 2) H2CO3 decomposes into H2O and CO2, which enter the tubule cell 3) tubule cells obtain CO2 from blood, and tubular fluid 4) CAH combines H2O and CO2 to re-form H2CO3 5) H2CO3 ionizes to form HCO3- (which returns to the blood) and H

using this figure as a guide, order the events during neutralization of hydrogen ions in the kidney from the movement H2CO3 forms until HCO3- returns to blood. begin with the formation of H2CO3 in the blood. • CAH combines H20 and CO2 to re-form H2CO3 • H2CO3 decomposes into H2O and CO2, which enter the tubule cell • H2CO3 ionizes to form HCO3- (which returns to the blood) and H • H in blood reacts with HCO3- to form H2CO3 • tubule cells obtain CO2 from blood, and tubular fluid

a) edema + b) water retention + c) hypertension

what are possible consequences of hypernatremia? select all that apply. a) edema b) water retention c) hypertension d) cellular swelling

d) disturbances in acid-base balance

what is the primary effect of chloride imbalances? a) hypertonic hydration b) muscular weakness, depressed reflexes and cardiac arrhythmia c) hypokalemia d) disturbances in acid-base balance

a) it is the greatest determinant of intracellular osmolarity and cell volume + b) it is an essential cofactor for protein synthesis and some other metabolic processes + d) it plays a role in cotransport and thermogenesis via the Na+-K+ pump + e) it helps produce the resting membrane potentials and action potentials of nerve and muscle cells

which are functions of potassium? select all that apply. a) it is the greatest determinant of intracellular osmolarity and cell volume b) it is an essential cofactor for protein synthesis and some other metabolic processes c) it is the most important anion of the extracellular fluid d) it plays a role in cotransport and thermogenesis via the Na+-K+ pump e) it helps produce the resting membrane potentials and action potentials of nerve and muscle cells

a) it participates in cotransport of glucose, K+ and Ca+ b) it is involved in generating body heat via the Na-K pump c) it participates in muscle and nerve depolarization

which are important functions of sodium? select all that apply. a) it participates in cotransport of glucose, K+ and Ca+ b) it is involved in generating body heat via the Na-K pump c) it participates in muscle and nerve depolarization d) it is used as an important fuel source for cellular respiration

b) heavy sweating, chronic vomiting or diarrhea + c) aldosterone hypersecretion + d) excessive use of laxatives + e) alkalosis

which are possible causes of hypokalemia? select all that apply. a) crush injury or hemolytic anemia b) heavy sweating, chronic vomiting or diarrhea c) aldosterone hypersecretion d) excessive use of laxatives e) alkalosis

a) dehydration + c) volume depletion

which are types of fluid deficiency? choose two of the options from the list below. a) dehydration b) hypotonic hydration c) volume depletion d) thirst

a) volume excess + d) hypotonic hydration

which are types of fluid excess? select all that apply. a) volume excess b) hypovolemia c) circulatory shock d) hypotonic hydration

c) a condition in which excess fluid accumulates in a particular location

which best defines fluid sequestration? a) a condition that occurs when a person rehydrates with plain water after profuse sweating b) a condition caused by renal failure c) a condition in which excess fluid accumulates in a particular location d) a condition caused by aldosterone hypersecretion

d) it increases the number of Na+-K+ pumps in the nephron

which best describes how aldosterone acts as the "salt retaining hormone"? a) it inhibits the osmoreceptors in the hypothalamus b) it inhibits atrial natriuretic peptide c) it causes release of ADH d) it increases the number of Na+-K+ pumps in the nephron

a) the kidneys can slow down the rate of water and electrolyte loss through changes in urine volume and composition

which best describes the role of the kidneys in maintaining water balance during dehydration? a) the kidneys can slow down the rate of water and electrolyte loss through changes in urine volume and composition b) kidney cells release the hormone ADH c) the kidneys can completely prevent water loss by inhibiting urine production d) the kidneys can replace lost fluid through the production of metabolic water

a) pleural effusion + d) hemorrhage

which can cause fluid sequestration? select all that apply. a) pleural effusion b) dehydration c) profuse sweating d) hemorrhage

d) ADH hypersecretion

which can cause hypotonic hydration? a) aldosterone hypersecretion b) ADH hyposecretion c) aldosterone hyposecretion d) ADH hypersecretion

a) diarrhea + b) chronic vomiting + d) hemorrhage

which factors can lead to volume depletion (hypovolemia), in which proportionate amounts of water and sodium are lost? select all that apply. a) diarrhea b) chronic vomiting c) profuse sweating d) hemorrhage

b) the pH of their working environment + c) the concentration of the buffer

which factors determine the amount of acid or base that can be neutralizes by a chemical buffer system? select two answers below. a) the temperature of the solution b) the pH of their working environment c) the concentration of the buffer d) the pressure in the working environment

potassium

which ion is the most abundant cation of the intracellular fluid and has the greatest impact on intracellular osmolarity and cell volume?

a) sodium

which ion is the principal cation of the ECF? a) sodium b) potassium c) phosphate d) chloride

a) they control the movement of water between fluid compartments

which is an important function of electrolytes in the ECF? a) they control the movement of water between fluid compartments b) they are important enzymes c) they transport nutrients from the digestive tract to the liver d) they create channels that move molecules across the cell membrane

b) metabolic water

which is produced as a by-product of dehydration synthesis reactions and aerobic respiration? a) interstitial fluid b) metabolic water c) transcellular fluid d) urine

a) metabolic water

which is produced as a by-product of dehydration synthesis reactions and aerobic respiration? a) metabolic water b) urine c) transcellular fluid d) interstitial fluid

b) hypovolemia

which may occur when proportionate amounts of water and sodium are lost without replacement, for example due to hemorrhage, chronic vomiting, or diarrhea? a) hypotonic hydration b) hypovolemia c) low osmolarity d) dehydration

a) dehydration

which occurs when the body eliminates more water than sodium, so that the ECF osmolarity rises? a) dehydration b) hypervolemia c) volume depletion d) hypotonic hydration

d) kidney

which organ can neutralize more acid or base than either the respiratory system or the chemical buffers? a) stomach b) pancreas c) liver d) kidney

b) respiratory system

which physiological buffer system exerts an effect within a few minutes but cannot alter the pH as much as the urinary system? a) integumentary system b) respiratory system c) muscular system d) reproductive system

b) pH

which property of a solution is determined by the concentration of hydrogen ions? a) osmolarity b) pH c) pressure d) temperature

b) sodium is more abundant in the ECF and potassium is more abundant in the ICF

which statement is correct regarding the relative abundance of electrolytes in the ECF and ICF? a) sodium and potassium are both more abundant in the ICF as compared to the ECF b) sodium is more abundant in the ECF and potassium is more abundant in the ICF c) sodium and potassium are both more abundant in the ECF as compared to the ICF d) potassium is more abundant in the ECF and sodium is more abundant in the ICF

a) hypotonic hydration

which term (also called water intoxication or positive water balance), refers to a condition in which more water than sodium is retain or ingested? a) hypotonic hydration b) volume excess c) volume depletion d) fluid sequestration

a) hypovolemia

which term is another name for volume depletion? this occurs when proportionate amounts of both water and sodium are lost without replacement. a) hypovolemia b) sequestration c) hypotonic hydration d) dehydration

d) hyperchloremia

which term refers to a plasma concentration of chloride greater than 105mEq/L? a) hypokalemia b) hyperkalemia c) hypochloremia d) hyperchloremia

c) metabolic water

which term refers to water that is produced as a by-product of dehydration synthesis reactions and aerobic respiration? a) excreted water b) preformed water c) metabolic water d) secreted water

a) osmoreceptors detect the increase in osmotic pressure of body fluids and signal the posterior pituitary

which triggers the release of ADH? a) osmoreceptors detect the increase in osmotic pressure of body fluids and signal the posterior pituitary b) thickened saliva signals the sympathetic nervous system c) the juxtaglomerular apparatus senses the greater osmostic pressure in the blood d) chemoreceptors in kidney tubules sense the increased viscosity of renal filtrate

a) respiratory system + d) urinary system

which two organ systems form physiological buffers that help stabilize pH by controlling the body's output of acids, bases or CO2? select two options from the list below. a) respiratory system b) muscular system c) integumentary system d) urinary system e) reproductive system

a) chemical

which type of buffer is defined as a substance that binds H+ and removes it from solution as its concentration begins to rise, or releases H+ into solution as its concentration falls? a) chemical b) physiological c) organic d) volatile

b) sensible

which type of water loss is noticeable output, particularly through the urine and in case of sufficient sweating to produce obvious wetness of the skin? a) obligatory b) sensible c) insensible

c) 7.4

which would be considered a normal pH value for arterial blood? a) 6.4 b) 8.5 c) 7.4 d) 7.0

d) they have higher metabolic rates and produce toxic metabolites faster

why are infants more vulnerable to dehydration than adults? a) babies and young children cannot sweat b) they have a lower body surface to volume ratio c) their kidneys produce more concentrated urine d) they have higher metabolic rates and produce toxic metabolites faster

c) they are consumed by neutralizing H+

why are there no bicarbonate ions in urine of a person with normal acid-base balance? a) they diffuse into the renal tubules b) they are secreted by the renal tubule cells c) they are consumed by neutralizing H+ d) they are exchanged for Cl-

c) calcium phosphate crystals would precipitate in the cytoplasm if levels were high

why do cells maintain a very low intracellular calcium concentration? a) intracellular calcium inhibits cellular processes such as exocytosis and muscle contraction b) calcium is not biologically important c) calcium phosphate crystals would precipitate in the cytoplasm if levels were high d) calcium only plays a role outside the cell, not in the cytoplasm

c) sympathetic output from the hypothalamus inhibits the salivary glands + d) lower capillary blood pressure and higher osmolarity of the blood leads to a decrease in saliva production

why do people salivate less when they are thirsty? select all that apply. a) ADH production inhibits hypothalamic osmoreceptors b) decreased angiotensin II production inhibits salivary glands c) sympathetic output from the hypothalamus inhibits the salivary glands d) lower capillary blood pressure and higher osmolarity of the blood leads to a decrease in saliva production