CHLORIDE, MAGNESIUM, POTASSIUM ....

Question 1

The major intracellular cation in the body.

● With a concentration 20 times greater inside the cells than
outside.

Answer 1

POTASSIUM

Question 2

As a result, only _____ of the body’s total K+ circulates in the
plasma.

Answer 2

2% - POTASSIUM

Question 3

Functions of K+ in the body include ___________, ___________, _______, __________

Answer 3

regulation of neuromuscular excitability, contraction of the heart,
ICF volume, and H+ concentration.
(RCIH)

Question 4

The internal environment of the cell is negatively charged when at
rest.

Answer 4

Resting Membrane Potential

Question 5

● Has a charge of -70 mv

Answer 5

Resting Membrane Potential

Question 6

Passively and continuously leaks out potassium outside

Answer 6

Potassium Channel

Question 7

When the cells receives a stimuli, and an action has to be
performed, the intracellular space must be positive

Answer 7

Excitation

Question 8

During cell excitation, sodium enters the cell to create a
positive charge, rather than releasing ___________

Answer 8

potassium outside

Question 9

In membrane potential has three (depolarization)

Answer 9

1. Threshold of excitation
2. Intracellular NA increases
3. Extracellular K increases

Question 10

the cell’s electrical charge becomes more positive and less negative

Answer 10

Depolarization

Question 11

the process by which a cell returns to its resting electrical state
after a depolarization (change from negative to positive charge),
typically involving the efflux of potassium ions.

Happens when potassium is move out from the cell
○ Same reason with sodium, it is easier and faster for
potassium to be expelled outside the cell as the
concentration of the cell is less outside.
○ Aside from that the channels of plasma membrane favors
more potassium rather than sodium

Answer 11

Repolarization

Question 12

is when a cell’s electrical charge becomes even more negative
than its usual resting state, making it less likely to fire an
electrical signal.
○ Happens as there is an increase of potassium outflow due
to the fact that potassium channels take time to close.

Answer 12

Hyperpolarization

Question 13

The pump helps establish and maintain the resting membrane
potential of a cell.
○ By pumping three sodium ions out of the cell and two
potassium ions into the cell against their respective
concentration gradients.
○ This process ensures that there are more sodium ions
outside the cell and more potassium ions inside.

Answer 13

Sodium-Potassium Pump

Question 14

The proximal tubules reabsorb nearly all the K+
○ Under the influence of aldosterone, additional K+ is
secreted into the urine in exchange for Na+ in both the
distal tubules and the collecting ducts

Answer 14

REGULATION OF POTASSIUM

Question 15

○ Thus ___________ is the principal determinant of urinary
K+ excretion

Answer 15

Distal nephron

Question 16

3 RENAL PROCESSES

Answer 16

Glomerular Filtration
Tubular Reabsorption
Tubular Secretion

Question 17

Substances are filtered based on size and charge . Ions are
filtered

Answer 17

Glomerular Filtration:

Question 18

Reabsorption of essential nutrients is being done, majority of
which happens at Proximal Convoluted Tubule (PCT)
● Direction: ______________

Answer 18

Tubular Reabsorption: Tubules to circulation

Question 19

Direction: _____________
● Occurs in the Distal Convoluted Tubules (DCT) and Collecting
Ducts

Answer 19

Tubular Secretion: circulation to the tubules

Question 20

It serves to eliminate waste products that were not filtered by the
glomerulus.
● High pressure in the glomerulus prevents all waste products from
being filtered, causing some to be returned to the blood vessels
around the nephron.

Answer 20

Tubular Secretion

Question 21

The secretion of potassium in DCT and Collecting Ducts is under
the influence of _________

Answer 21

aldosterone

Question 22

Aldosterone stimulates both parts of the ________ to
reabsorb sodium at the expense of potassium

Answer 22

nephron

Question 23

The kidney reabsorbs filtered K+ in ____________ and _________

Answer 23

hypokalemic states and secretes K+ in hyperkalemic states

Question 24

Also, only our _________ can eliminate potassium. Thus, it is very
important to know if your kidneys are working

Answer 24

kidneys

Question 25

3 FACTORS THAT INFLUENCE THE DISTRIBUTION OF K+ BETWEEN CELLS AND ECF

Answer 25

Potassium, Insulin, Catecholamines

Question 26

_____________ loss frequently occurs whenever the Na-K ATPase pump is inhibited by conditions (hypoxia, hypomagnesemia, *digoxin overdose)

Answer 26

Potassium

Question 27

promotes acute entry of K ions into skeletal muscle and liver by increasing Na-K ATPase activity

Answer 27

Insulin

Question 28

_____________ promote cellular entry of K, whereas ___________ impairs cellular entry of K activity

Answer 28

Catecholamines; propranolol

Question 29

_______________(adrenaline) & _____________ (noradrenaline)

Answer 29

Epinephrine norepinephrine

Question 30

■ Flight and fight

Answer 30

Epinephrine

Question 31

Medication for the heart ■ Beta blocker ■ Possible that our potassium increases in our blood if it cannot enter the cell

Answer 31

○ Propranolol

Question 32

K is released from cells during _________

Answer 32

exercise

Question 33

In exercise Increases K by __________ mmol/L

Answer 33

0.3 – 1.2 mmol/L

Question 34

Reversed after several minutes of rest

Answer 34

exercise

Question 35

● ____________ during venipuncture can cause erroneous high plasma K concentrations or _____________

Answer 35

Forearm exercise - pseudohyperkalemia

Question 36

______________ as with uncontrolled diabetes mellitus, causes water to diffuse from the cells, carrying K+ with the water, which leads to gradual depletion of K+ if kidney function is norma

Answer 36

HYPEROSMOLALITY

Question 37

_________ into the ECF when cells are broken down ●___________, _______, __________

Answer 37

CELLULAR BREAKDOWN Releases K Severe trauma, tumor lysis syndrome, and massive blood transfusions (STM)

Question 38

● Low potassium in the blood

Answer 38

HYPOKALEMIA

Question 39

HYPOKALEMIA DUE TO GASTROINTESTINAL LOSS (6)

Answer 39

(VDGIMC) Vomiting ● Diarrhea ● Gastric suction ● Intestinal tumor ● Malabsorption ● Cancer therapy (chemotherapy, radiation therapy)

Question 40

Inhibits Na-Cl co-transporter leading to the secretion of K via potassium channels in the collecting duct

Answer 40

● Diuretics (Thiazides and Loop)

Question 41

___________is the most common cause of hypokalemia

Answer 41

(The use of ) diuretics

Question 42

drugs that are promoting diaphoresis or excretion of water from the body

Answer 42

Diuretics

Question 43

Inhibits the reabsorption of sodium

Answer 43

Thiazides

Question 44

If you're drinking these two diuretic, dapat may third drug na ma add , si ________________

Answer 44

potassium sparing diuretics

Question 45

Due to increased accumulation of acid in the body, more bicarbonate ions will be excreted together with K+

Answer 45

● Renal Tubular Acidosis

Question 46

pH of Blood: ______________

Answer 46

7.35-7.45

Question 47

A condition in which the adrenal gland produces too much aldosterone ○ More Na ions will be retained in exchange of K ions ○ You are reabsorbing more sodium

Answer 47

● Hyperaldosteronism

Question 48

Low magnesium levels in the blood ○ Potassium channels or Renal Outer Medullary K+ (ROMK) Channel are inhibited by magnesium

Answer 48

● Hypomagnesemia

Question 49

In alkalemia (a condition where the blood becomes more alkaline), cells take up more potassium (K+) because alkalemia causes the cells to lose hydrogen ions (H+) in order to balance and reduce their internal pH level.

Answer 49

● Alkalosis

Question 50

Low potassium in blood ● In healthy persons, an acute oral load of K+ will briefly increase plasma K+ because most of the absorbed K+ rapidly moves intracellularly

Answer 50

HYPOKALEMIA

Question 51

CAUSES OF HYPERKALEMIA (DCIA) DECREASED RENAL EXCRETION (4) CELLULAR SIFT (5) INCREASED INTAKE (1) ARTIFICIAL (4)

Answer 51

DECREASED RENAL EXCRETION (AHAD) Acute or chronic renal failure (GFR < 20 mL/min ) ● Hypoaldosteronism ● Addison’s disease ● Diuretics CELLULAR SIFT (AMCLH) ● Acidosis ● Muscle /Cellular injury ● Chemotherapy ● Leukemia ● Hemolysis INCREASED INTAKE (O) Oral or intravenous potassium replacement therapy ARTIFICIAL (STGPR) ● Sample hemolysis ● Thrombocytosis ● Prolonged tourniquet use or excessive fist clenching ● GFR, glomerular filtration rate

Question 52

● Major Extracellular Anion

Answer 52

CHLORIDE ION

Question 53

Function of Chloride ○ Involved in maintaining _________, _______, _______

Answer 53

osmolality, blood volume, and electric neutrality OBE

Question 54

Physiology & Regulation ○ Main source: __________________ ■ We get chloride from our food along with other electrolytes that are absorbed in the gastrointestinal system. ○ Kidney: _________ and __________ ○ Excess chloride is excreted in ___________ and _______

Answer 54

DIET - GI absorption filtration and reabsorption in PCT urine and sweat

Question 55

Excessive sweating stimulates aldosterone secretion - _____________

Answer 55

sweat glands

Question 56

○ Act as rate-limiting component

Answer 56

● Electrical Neutrality

Question 57

CI- diffuses into the red blood cell to maintain electroneutrality ○ The movement of chloride from the plasma into our RBC (replacing the leaving bicarbonate which is also an anion)

Answer 57

● Chloride shift

Question 58

__________ it’s a byproduct of our body and has to be removed through RBCs.

Answer 58

CO2

Question 59

CO2 will bind to water via____________ to form_______________

Answer 59

Carbonic anhydrase to form Carbonic acid (H2CO3)

Question 60

Excess loss of HCO3

Answer 60

HYPERCHLOREMIA

Question 61

Excess loss of Cl-

Answer 61

HYPOCHLOREMIA

Question 62

HYPERCHLOREMIA as a result of: (3)

Answer 62

● RBC will give off chloride instead, since bicarbonate is insufficient (chloride levels will increase) ● GI losses ● RTA or Metabolic Aldosterone acidosis

Question 63

HYPOCHLOREMIA (4)

Answer 63

● Prolonged vomiting (will lead to a poor absorption of our electrolytes) ● Diabetic ketoacidosis ● Aldosterone deficiency (sodium will not be reabsorbed and chloride will not also be reabsorbed) ● Salt-losing nephropathy (pyelonephritis)

Question 64

Fifth most common element and is the most prevalent cation in the human body

Answer 64

CALCIUM

Question 65

Sodium is prevalent in the __________ while calcium are prevalent in our __________

Answer 65

plasma - bones

Question 66

Majority of our calcium is stored in our _________, they are not __________ and are not _________

Answer 66

bones not physiologically active and not circulating

Question 67

FUNCTIONS OF CALCIUM

Answer 67

Skeletal mineralization (stored as hydroxyapatite) ● Blood coagulation serves as Clotting Factor IV ● Neural transmission ○ calcium propagate signals down our axons ○ are also involved in dumping neurotransmitters like acetylcholine, into our synapses (calcium is needed by the acetylcholine to leave the terminal end of the axon and enter the synaptic cleft, and bind to its receptor) ● Pasma buffering capacity and enzyme activity ● Maintenance of normal muscle tone and excitability of skeletal and cardiac muscle (because it has a connection with our signals coming from the nerve cells)

Question 68

DISTRIBUTION OF CALCIUM _______ bone(as hydroxyapatite) ● ______ - circulation (blood) + ECF ● ______ is further divided into 3 different types of calcium: ○ ______ - bound to anions ○ _______- bound to protein (albumin) ○ ________-Free/ ionized Ca*+

Answer 68

99% > bone(as hydroxyapatite) ● 1% - circulation (blood) + ECF ● 1% is further divided into 3 different types of calcium: ○ 10% - bound to anions ○ 40% - bound to protein (albumin) ○ 50% -Free/ ionized Ca*+

Question 69

In the laboratory, they are ____________ Calcium results will include calciums that are bound to proteins and anions

Answer 69

hard to measure alone.

Question 70

Some labs have separate tests for total calcium and free/ionized calcium ○ Total calcium may look normal but free/ionized calcium may be low, leading to _______ and _______

Answer 70

conditions and erroneous results

Question 71

Decreased free calcium levels in the blood can cause muscle spasms or uncontrolled muscle contractions called __________

Answer 71

tetany

Question 72

3 HORMONES THAT REGULATE CALCIUM

Answer 72

1. PTH: secreted in low calcium levels 2. Vitamin D 3. Calcitonin: secreted in high calcium levels

Question 73

Trigger or stimulus to increase calcium levels remember 99% of calcium is stored in bones (meaning pwedeng kumuha doon sa bone ng excess calcium) kasi only 1% of our calcium circulates on plasma ● once you experience low calcium level on your body it will release PTH, and this PTH will trigger bone resorption meaning there is a breakdown of parts of bone in order to release calcium from bone into circulation thereby normalizing low calcium levels

Answer 73

1. PTH: secreted in low calcium levels

Question 74

Triggers to increase the absorption of calcium in our diet and also help our PTH in bone resorption. ● Target: to increase calcium level in blood

Answer 74

2. Vitamin D

Question 75

Secreted by thyroid gland ● Secreted in high calcium level (opposite of both PTH and Vit. D) ● If mataas ang calcium level sa blood, calcitonin will be released by thyroid gland to excrete excess calcium and will become normal level in blood) ● Meaning ginapababa niya ang calcium level

Answer 75

3. Calcitonin: secreted in high calcium levels

Question 76

an inactive substance in the skin

Answer 76

7-dehydrocholesterol

Question 77

● still an inactive form of vitamin D ● Produced when 7-dehydrocholesterol is exposed to UV Light

Answer 77

1. Cholecalciferol or vitamin D3

Question 78

● Both of them, will enter liver and be converted to calcidiol (25-hydroxyvitamin D) ● Still an inactive form of vit. D ● Will enter kidney and will form an active form of vitamin D

Answer 78

2. Ergocalciferol or Vitamin D2

Question 79

l (1, 25-dihydroxyvitamin D or 1,25-dihydroxycholecalciferol (1,25-[OH]2 -D3 ) - has power to induce certain changes in our body to increase calcium levels in plasma The active form of Vitamin D ● To increase intestinal absorption of calcium in our diet ○ Induce to increase bone resorption, hence prompting breakdown of the bone, causing the release of calcium into circulation ○ Lastly, it decreases the excretion of calcium as well as phosphate.

Answer 79

3. Calcitriol

Question 80

a reserve and will be activated by thyroid hormone

Answer 80

Inactive metabolite (24, 25-dihydroxyvitamin D

Question 81

In summary

Answer 81

7-dehydrocholesterol → UV light exposure → Cholecalciferol + Ergocalciferol (from diet) → Enter together in the liver and undergo hydroxylation → Calcidiol → Hydroxylated in the Kidney → Calcitriol (Active form of Vitamin D) ○ Hence to make an active form of vitamin D Cholecalciferol must undergo two hydroxylation processes first from the liver second in the kidneys.

Question 82

Increase the level of calcium in our blood and trigger or stimulus is low in calcium levels ● To increase or to normalize low calcium level

Answer 82

PARATHYROID HORMONE

Question 83

PARATHYROID HORMONE ● 3 MAJOR EFFECTS: (BCS)

Answer 83

○ Bone resorption ○ Conserves Ca2+ by increasing tubular reabsorption ○ Stimulates renal production of active vitamin D

Question 84

____________ is not good because calcium tends to deposit in our body

Answer 84

Hypercalcemia

Question 85

Fourth most abundant cation ● Second most abundant intracellular ion

Answer 85

MAGNESIUM

Question 86

MAGNESIUM ○ ______ - bone ○_______ - muscle and other organs and soft tissue ○ Less than ______ serum and erythrocytes ■ Protein-bound (primarily albumin) ■ Free or ionized form : major ■ Complexed with other ions

Answer 86

53% 46% 1%

Question 87

Function of magnesium (5)

Answer 87

Functions:ETNSR ● Essential cofactor - example are ALP & ACP ● Transcellular ion transport- transports of ion from apical surface to basolateral surface ● Neuromuscular transmission ● Synthesis of carbohydrates, proteins. Lipids, and nucleic acid ● Release of and responds to certain hormones

Question 88

MAGNESIUM Controlled largely by the __________ ● Non-protein-bound are filtered by the glomerulus ○ __________ is reabsorbed by the PCT ○ _______ is reabsorbed in ascending loop of Henle ● Renal threshold: _________

Answer 88

Kidney 25-30% 50-60% 0.60-0.85 mmol/L

Question 89

○ Increases renal reabsorption and intestinal absorption ○ Main target is calcium and not magnesium, but it will initiate reabsorption and intestinal absorption of calcium and madadamay ang si magnesium( so it is moe in calcium than in magnesium)

Answer 89

PTH

Question 90

○ Increases the renal excretion of magnesium ○ To eliminate magnesium in our bod

Answer 90

● Aldosterone and thyroxine