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Chapter 25 Review

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At which stage of life is the percentage of fluid in the human body highest?
Infancy
In elderly individuals, 75% of body weight is made up of fluid. (T or F)
False
When comparing two individuals of the same body weight, the one with more muscle and less fat will have a ____ percentage of ____ in their body
Higher/fluid
When comparing a lean adult female to a lean adult male, which will most likely have a higher percentage of body fluid?
The male
Fluid imbalances are more common in individuals with a ____ percentage of body fluid.
Low
Elderly individuals generally have a ____ percentage of body fluid and are therefor ____ prone to fluid imbalances.
Low/more
A comparison of the two major body fluid compartments reveals that
Two thirds of the total fluid is within our cells and one third is outside our cells.
Most of the fluid in our body is contained within our
Cells
The plasma of our blood constitutes ____ than half of the fluid in our body; plasma is part of the ____ fluid.
Less/extracellular
Interstitial fluid composes about ____ of the body's extracellular fluid.
2/3
Interstitial fluid has a relatively ____ concentration of sodium and chloride; the concentrations of ions within the interstitial fluid and blood plasma are very ____.
High/different
Which statement accurately describes the permeability to water of the cell membrane and the capillary wall?
Both the plasma membrane and the capillary wall are permeable to water
Drinking a liter of water will cause the osmolarity of blood plasma to
Decrease
If someone runs a marathon through a desert while eating pretzels and not drinking water, their plasma osmolarity
Rises and becomes hypertonic to the interstitial and intracellular fluid compartments.
As an individual becomes dehydrated, the net movement of fluid in their body is from ____ toward ____.
Cells/plasma
When fluid intake equals fluid output, and there is a normal distribution of solvent and solutes in the body's fluid compartments, fluid ____ exists.
Balance
Which type of intake accounts for most of our daily fluid intake?
Preformed water
Water lost through feces is considered ____ water loss.
Sensible, obligatory
Facultative water loss is loss that
Is controlled by hormone effects on the kidney
In the condition of volume excess, fluid gain involves
No change in the osmolarity of body fluidd
If someone in an accident suffered severe burns as well as hemorrhage, they would be at high risk for
Volume depletion
Renal failure would likely lead to
Volume excess
Diabetes mellitus, profuse sweating, and hyposecretion of ADH can each lead to
Dehydration
If a runner drinks too much water before a marathon, they run a risk f water intoxication, also known as
Hypotonic hydration
Extreme hypotonic hydration can cause brain cells to
Swell
Edema is an example of
Fluid sequestration
Blockage of lymphatic vessels or surgical removal of lymphatic vessels increases the liklihood of
edema, which is an example of fluid sequestration
Feelings of thirstiness are brought on by
Decreases in salivary secretions and increases in blood osmolarity
Decreases in blood pressure turn ____ the thirst center of the brain
On
Fluid intake causes blood volume to
Increase
The thrist center f the brain is located in the
Hypothalamus
Researchers have inflated balloons inside the stomachs of experimental subjects and have found that distention of the stomach causes thirst to
Decrease
Which of the following does not turn off te thirst center of the brain
Decreased salivary secretions
When compared with the effects of blood pressure and osmolarity on fluid intae, the effects of saliva and stomach distention are more ____ but less ____.
Immediate/accurate
Angiotensin II, aldosterone, and ADH each help decrease
Urine output
The hormone ANP
Increases urine output and decreases blood volume
Fixed acids are generally regulated by physiological buffering provided by the
kidneys
Most nonelectrolytes are ____ bonded ____ molecules
Covalently/organic
The molecule HCl is an example of a(n)
Electrolyte
To account for their effects on osmotic pressure, the concentration of electrolytes is often expressed in
Milliequivalents per liter
When NaCl is added to body fluids it results in the addition of
Two solute particles per NaCl molecule and exerts twice the osmotic pressure of the same number of nonelectrolyte molecules
The most abundant cation within cells is
Potassium
The most abundant anion in the extracellula fluid is
Chloride
Which ion is the principal solute of the ECF and is crucial for neuromuscular and renal function?
Sodium
How are sodium levels and blood pressure related?
Increased plasma sodium levels increase water retention, blood volume, and blood pressure
Most potassium loss from the body occus through
Urine
When the pH of the ECF decreases, K+ starts to move from the
ICF to the ECF
Insulin causes blood plasma levels of potassium to ____ by ____ activity of the Na+/K+ pumps
Decrease/stimulating
An elevated level of potassium in the blood is referred to as
Hyperkalemia
How does the hormone aldosterone influence potassium levels?
It increases potassium secretion by the kidnets and decreases potassium blood concentration
Calcium hardens bone and teeth, but it levels are carefully controlled throughout the body. Low levels of calcium within cells are maintained by
Pumps that move calcium out of cells or into the sarcoplasmic reticulum
Angiotensin II triggers
Vasoconstiction and decreased urine output from the kidneys
Angiotensin II causes a(n)
stimulation of the thirst center and increased release of ADH
Angiotensin II stimulates the adrenal cortex to release
Aldosterone
Antidiuretic hormone (ADH) is synthesized in the ____ and released from the____.
Hypothalamus/posterior pituitary
Changes in blood osmolarity within capillaries of the hypothalamus are a signal for ADH release. The neurons that are sensitive to these changes in osmolarity are?
Chemoreceptors
High levels of ADH cause
Vasoconstriction and therefore increases in blood pressure
The adrenal gland releases aldosterone in response to
Angiotensin II and decreased blood plasma sodium levels
Aldosterone exerts effects on principal cell of the kidney by causing
Increased numbers of Na+/K+ pumps
Aldosterone causes kidny tubules to
Reabsorb more sodium and water, and secrete more potassium
The stimulus that directly triggers release of ANP is
Increased stretch of the heart atria
The hormone ANP causes systemic blood vessels to
Dilate, which lowers blood pressure
Atrial natriuretic peptide causes ____ of afferent arterioles and ____ of mesangial cells.
Dilation/relaxation
Atrial natriuretic peptide (ADP) inhibits the release of
Aldosterone, ADH and renin
In the brain ADH ____ the thirst center, and in the kidneys ADH causes an increase in water ____.
Stimulates/reabsorption
Carbonic acid is referred to as ____ acid since it is produced from a gas that evaporates quickly
Volitile
Most of the fixed acid in our body comes from
Acid absorbed from the GI tract
Severe diarrhea leads to a ____ in the ____ of the blood
Decrease/pH
When blood starts to become more alkaline than normal the renal tubules begin to
Secrete bicarbonate while reabsorbing H+ in exchange through type B cells
The process by which the kidneys eliminate excess acid or base is relatively
Slow (takes hours to days) but powerful
If someone begins to hyperventilate due to anxiety, the CO2 concentration in their blood decreases; this causes ____ in blood pH
An increase
The amine groups contained within amino acids of proteins can act as weak
Bases
Both intracellular proteins (such as hmoglobin) and extracellular proteins (such as plasma proteins) can act as
Chemical buffers
If a strong acid were to add H+ to the intracellular fluid, the effect would most likely be buffered, as
HPO42-would act as a weak base and accept an H+ to become H2PO4
The bicarbonate buffering system is the most important buffering system in the
extracellular fluid
When bicarbonate acts as a weak base and accepts a proton, the molecule ____ acid is formed
Carbonic
Water occupies two main fluid compartments within the body, the intracellular fluid compartments and the extracellular fluid compartment. Which of the following statements is true concerning the volume of intracellular fluid?
Approximately two thirds of the water is in the intracellular fluid compartment
Individuals with a lower percentage of body fluid are more susceptible to
Fluid imbalance
When the body cells are hypotonic to the blood plasma, water will move from ____ fluid to ____ fluid.
Intracellular/extracellular
On a hot day where fluid output ____ fluid intake, the body is in a danger of a fluid imbalance
Exceeds
Drinking alcohol increases the production of dilute urine, dehydrating the body. In this example, decreasing preformed water intake will help rehydrate the body. (T or F)
False
Which stimulus for increasing thirst and water intake is monitored by the thirst center directly?
Increased blood osmolarity
A decrease in blood pressure
results in the release of renin from the kidneys
When blood osmolarity drops
ADH release is decreased
Carbonic acid dissociates into a bicarbonate ion and hydrogen ion, thereforeit is a(n)
Electrolyte
The magnesium ion is a major electrolyte in the body (T or F)
True
Ingesting too much sodium may lead to
Hypertonic extracellular fluid
Sodium is an important electrolyte because
It contributes significantly to blood plasma osmolarity
The most abundant anion in the extracellular fluid is the
Chloride ion
Antiduretic hormone release results in
Increased water reabsorption in the kidneys
Since aldosterone increases retention of sodium, blood osmolarity is increased as a result. (T or F)
False
A patient who secretes too much atrial natriuretic peptide may be in danger of
Low blood pressure
Atrial natriuretic peptide stimulates the kidneys to retain sodium, whereas aldosterone stimulates the kidneys to eliminate more sodium in the urine. (T or F)
False
Lactic acid is an example of a ____ acid.
Fixed
A diabetic patient has high levels of ketoacids in his blood. What organ system will help regulate this acid?
Urinary
As blood pH becomes too high, the kidneys
Reabsorb H+
When carbon dioxide levels are low in the blood plasma, pH may be too high. The respiratory system ____ ventilation, resulting in more plasma carbon dioxide and a lowered pH
Decreases
In the phosphate buffering system, a strong acid is buffered to produce a weak base. (T or F)
False
A patient has a PCO2 of 50 mmHg. In other words, this patient has
Respiratory acidosis
Metabolic acid-base disturbances occur when changes in respiratory function results in particularly high or low levels of plasma carbon dioxide. (T or F)
False
When arterial blood levels of bicarbonate exceed 26 mEq/L, this is known as
Metabolic alkalosis