Acid-Base

Question 1

The seven most important electrolytes in terms of body functioning are:

• So..
• Pot..
• Chl…
• Calc…
• Phos….
• Magne…
• Bic…

Answer 1

• Sodium (Na+), extracellular cation
• Potassium (K+) intracellular cation
• Chloride (Cl-) extracellular anion
• Calcium (Ca2+) extracellular cation
• Phosphate (HPO42-) Both, anion
• Magnesium (Mg2+) cation
• Bicarbonate (HCO3-) both, anion

Question 2

• Sodium is the major _____ of the _______ fluid and is responsible for _____ of osmotic pressure gradient
• Sodium is freely filtered through the glomerular capillaries of the _____, most is reabsorbed but…
• When we ingest sodium chloride (salt), what happens when we do

Answer 2

• Sodium is the major cation (positive) of the extracellular fluid and is responsible for ~1/2 of osmotic pressure gradient (water a bit negative, so attract)
• Sodium is freely filtered through the glomerular capillaries of the kidneys. Much is reabsorbed in the PCT but some remains in filtrate (normal) and is excreted in our urine
• ADH secreted and thirst increases as osmolarity increases

Question 3

• Potassium is the major ____ fluid ____ and it helps establish the resting membrane potential after…
• Potassium has very little effect on…. this is because low level of potassium maintained by..

Answer 3

• Potassium is the major intracellular cation and it helps establish the resting membrane potential after membrane depolarization and action potentials
• Potassium has very little effect on osmotic pressure because low levels of potassium in blood and CSF are maintained by the sodium-potassium pumps in cell membranes

Question 4

• Chloride is the predominant _____ fluid _____ and is a major contributor to the….
• Chloride functions to balance cations in the ECF by…

-***** _______ and ______ are reabsorbed from the renal filtrate, and ____ is excreted into the filtrate in the renal collecting tubule

• The control of this exchange is mainly governed by two hormones

Answer 4

• Chloride is the predominant extracellular anion and is a major contributor to the osmotic pressure gradient between the ICF and ECF
• Chloride functions to balance cations in the ECF, maintaining the electrical neutrality of this
  fluid
• Sodium and Chloride are reabsorbed from the renal filtrate, and potassium is excreted into the filtrate in the renal collecting tubule
• aldosterone and angiotensin II

Question 5

• Our body contains ~__ kg of calcium and it not only provides hardness to the bones and teeth but also…
• Calcium is not just found in our bones and teeth, it is also an ___ fluid _____ in our blood and is necessary for…(3)

Answer 5

• Our body contains ~1 kg of calcium and it not only provides hardness to the bones and teeth (99% in bones) but also serves as a mineral reserve for calcium and its salts for the rest of the tissues
• Calcium is not just found in our bones and teeth, it is also an extracellular cation in our blood and is necessary for muscle contraction, enzyme activity, and blood coagulation (1% of our calciuim)

Question 6

Signal Transmission at a Chemical Synapse

1. The action potential travels down the axon to the…
2. The electrical impulse opens voltage-gated channels, enabling…
3. The increased intracellular calcium triggers the synaptic vesicles to release… through exocytosis

Answer 6

1. The action potential travels down the axon to the synaptic end bulb of the presynaptic neuron
2. The electrical impulse opens voltage-gated channels, enabling calcium to flow in
3. The increased intracellular calcium triggers the synaptic vesicles to release their neurotransmitter into
   the synaptic cleft through exocytosis

Question 7

3 calcium hormones

• The most important regulator of calcium in our blood is what hormone, which increases what
• We also regulate the uptake of calcium in the small intestine via ____
• When blood calcium levels rise above homeostatic levels, the thyroid gland releases ______, which…

Answer 7

• The most important regulator of calciumin our blood is parathyroid hormone which increases reabsorption from bones via augmenting osteoclast activity and reabsorption at the kidneys
• Calcitriol (active form of vitamin D)
• the thyroid gland releases Calcitonin which inhibits osteoclast activity and promotes calcium uptake at the bones and teeth (less in blood). Inhibits osteoclast activity

Question 8

• Our bones and teeth using ~85% of the body’s phosphate as part of….
• Phosphate acts as a weak ________ to buffer…
• Phosphate is found in what 3 places

Answer 8

• Our bones and teeth using ~85% of the body’s phosphate as part of calcium-phosphate salts
• Phosphate acts as a weak base to buffer intracellular fluids
• Phosphate is found in phospholipid membrane surrounding our cells, in adenosine triphosphate (ATP), and as buffers

Question 9

• Magnesium is the predominantly found in..
• Magnesium activates several enzyme systems involved in…and is needed for…
• Bicarbonate is the second most abundant ____ in the blood and functions is to…in our blood
• bicarbonate ions made by combining what at end of aerobic metabolism via what enzyme to produce what which dissociates in what

Answer 9

• Magnesium is the predominantly found in the bone matrix
• Magnesium activates several enzyme systems involved in the metabolism of carbohydrates and proteins and is needed for operation of the sodium pump
• Bicarbonate is the second most abundant anion in the blood and functions is to maintain acid-
  base balance in our blood
• bicarbonate ions made by combining carbon dioxide and water at the end of aerobic metabolism via carbonic anhydrase. to produce carbonic acid which then disassociates into bicarbonate and hydrogen ions acid

Question 10

• Acidosis and alkalosis from… (ph ranges)
• A buffer is a chemical system that prevents a radical change in fluid pH by…

the buffer will be able to function as both
- weak a..
- weak b..

Answer 10

• Acidosis from ph drop below 7.35 due to increase hydrogen ions and becomes more acidic, below 7.0 fatal. Alkalosis is decreased hydrogen ions and ph rises over 7.4.5 due to accumulation of bases, pH above 7.8 is fatal
• dampening the change in hydrogen ion concentrations in the case of excess acid or base
• a weak acid (takes up hydroxyl ions)
• a weak base (takes up hydrogen ions)

Question 11

The buffer systems = extremely efficient in human, and different systems work at different rates (speeds)
- chemical buffers
- respiratory tract
- renal system

• 3 buffer systems functioning in blood plasma to maintain our pH

Answer 11

• The chemical buffers in the blood to adjust in seconds to pH
• The respiratory tract can adjust the blood pH upward in minutes by exhaling CO2
• The renal system = adjust blood pH through the excretion of hydrogen ions (H+) and the conservation of bicarbonate, hours to days
• Phosphate, proteins and bicarbonate-carbonic acid buffers

Question 12

• Phosphate buffer system is an effective buffer in..

Phosphate buffer system comprised of two ions
- mono
- di

• protein buffer system is the most (2)… in….because..
• The most important protein buffer is ____

Answer 12

• intracellular fluids (cytosol) and urine from the kidneys
• Monohydrogen phosphate ions (HPO42-) acts as a weak base
• Dihydrogen phosphate ions(H2PO4-) acts as a weak acid
• protein buffer system is the most abundant buffer in body cells and plasma as the protein molecule functions are both a weak acid and a weak base
• The most important protein buffer is hemoglobin

Question 13

• The most important buffer for maintaining the acid-base balance in the blood is

two types (weak acid and base)
- bicarb
- carb

• Bicarbonate ions and carbonic acid are present in the blood in what ratio
• why is the ratio favoured this way

Answer 13

• acid-base balance in the blood is the bicarbonate-carbonic acid buffer system
• Bicarbonate ions (HCO3-) acts as a weak base
• Carbonic acid (H2CO3) acts as a weak acid
• 20:1 ratio if the blood pH is within the normal range (more bicarb)
• This is useful because most of the body’s metabolic wastes are acids

Question 14

• The respiratory system contributes to the balance of acids and bases in the body by regulating the blood levels of…
• Increasing breathing at rest to leads to a decrease….causing a temporary increase…
• Decreasing breathing at rest leads to… causing a temporary decrease in…

Answer 14

• The respiratory system contributes to the balance of acids and bases in the body by regulating the blood levels of carbonic acid (when co2 increases, its excess reacts with water to make carbonic acid to decrease pH back down)
• Increasing breathing at rest to leads to a decrease in CO2 (and H+) causing a temporary increase in blood pH
• Decreasing breathing at rest leads to an increase in CO2 (and H+) causing a temporary decrease in
  blood pH

Question 15

• The renal regulation of the body’s acid-base balance regulate buffering system by controlling the blood levels of _______
• Even though……..are essential for buffering pH in our blood the cells of the tubule are not permeable to…
• The major effect from acidosis is…has several symptoms like…
• In contrast the major effect of alkalosis is an…symptoms of…

Answer 15

• The renal regulation of the body’s acid-base balance addresses the metabolic component of the buffering system by controlling the blood levels of bicarbonate
• Even though, bicarbonate ions are essential for buffering pH in our blood the cells of the tubule
  are not permeable to bicarbonate ions
• a depression of the central nervous system. (headache and confusion, and easily fatigued)
• over-excitability of the central and peripheral nervous systems. (cognitive impairment, tingling, muscle twitching, and nausea and vomiting)

Question 16

• A change in pH ↑ or ↓ can alter the shape of the enzymes in our body, affecting what two things

Both acidosis and alkalosis can be caused by either metabolic or respiratory alterations and the body will try to counter a change in pH from one system through compensation of the other
- two types on compensation

Answer 16

• Can become non-functional and affects metabolic activity
• Complete – pH is brought back within the 7.35-7.45 range
• Partial – pH is adjusted towards the normal range but is still <7.35 or >7.45

Question 17

• Respiratory acidosis refers to increased…causing…
• Respiratory alkalosis refers to decreased…causing…
• Metabolic acidosis refers to decreased…causing…
• Metabolic alkalosis refers to increased…causing…

Answer 17

• Respiratory acidosis refers to increased PaCO2 causing pH to drop <7.35
• Respiratory alkalosis refers to decreased PaCO2 causing pH to increase >7.45
• Metabolic acidosis refers to decreased HCO3- causing pH to drop <7.35
• Metabolic alkalosis refers to increased HCO3- causing pH to increase >7.45

Question 18

• If a person has altered pH for respiratory reasons what will compensate, how
• Respiratory acidosis is characterized by…. and is caused by ______ , how does renal compensate
• Respiratory alkalosis is characterized by…and is caused by ______. Renal compensation by..

Answer 18

• If a person has altered pH for respiratory reasons then the urinary system will compensate through
  either retention or excretion bicarbonate at the kidneys to alter pH (takes days
• Respiratory acidosis is characterized by an elevated PaCO2 and decreased pH and is caused by hypoventilation, renal compensation of excreting H+ and increased reabsorption of HCO3-
• Respiratory alkalosis is characterized by a decreased arterial blood PaCO2 and increased pH and is caused by hyperventilation. Renal compensation of excreting HCO3- and increased reabsorption of H+

Question 19

• If a person has altered pH for metabolic reasons what will compensate, how
• Metabolic acidosis is characterized by decrease of two things..and results from…. loss of bicarbonate from…. Respiratory compensation by….
• Metabolic alkalosis is characterized by increased what…. and results from…… Respiratory compensation via…

Answer 19

• then the respiratory system will compensate through either hyper- or hypoventilation to alter CO2
  to adjustment to pH (minutes to hours)
• Metabolic acidosis is characterized by a decreased bicarbonate level and decreased pH, and results from an abnormal increase in acid metabolic products (other than CO2), loss of bicarbonate from diarrhea, or failure of the kidneys to excrete H+ ions. Respiratory compensation via hyperventilation, decreasing PaCO2
• Metabolic alkalosis is characterized by increased bicarbonate concentration and results from non-respiratory loss of acid (e.g., excessive vomiting) or excess intake of alkaline drugs. Respiratory compensation via hypoventilation, increasing PaCO2