anatomy 2 acid base balance

why is hydrogen ion concenration important for homeostasis

many physiological functions and chemical reactions are snesitive to H ion changes: h ions concentration affects enzyme function and protein shape

which body system regulate hydrogen ion concentration

the respiratory system and urinary system, working with chemical buffers

what determines hydrogen ion concentration

the acids and bases present in a solution

what is an acid

a substance that releases hydrogen ions (protons) into a solution

what is a base

a molecule that accepts hydrogen ions (protons)

what is a strong acid

an acid that completely dissociated into ions in solution

what is a weak acid

an acid that does not completely dissociate in water; weak acids are common in living systems and help maintain pH homeostasis

give an example of a strong acid

hydrocjloric acid (HCl-); HCl → H → Cl-)

give an example of a weak acid

carbonic acid (H2CO3)

how does lactic acid behave in solution

ir releases only a fraction of its H+ ions:it is a weak acid. the slide say it can be broken down to CO2 and H2O, converted to glucose/ glycogen, or converted to pyruvate

which acidic byproduct are listed in the slides

carbonic acid, lactic acid, fatty acids, phosphoric acid, sulfuric acid, and CO2

what produces lactic acid

exercise

what produces fatty acids

lipid metabolism

what produces phosphoric and sulfuric acids

protein metabolism

how does metabolic rate affect CO2 production

as metablolic rate increases, CO2 production increases

what is a strong base

a base that completely dissociates: example sodium hydroxide and potassium hydeoxide

what weak bases are listed

ammonium and aluminum hydroxide (antacids)

what is pH

a measure related to the free hydrogen ion concentration in solution

what is the pH formula

pH= -log[H+]

what happpens to H+ concentration whrn pH decreases by one unit

H+ concentration increases 10 -fold

what is the pH of pure water

7; its neutral

what is an acidic solution

a solution with pH below 7 and a higher H+ concentration

what is an alkaline/ basic solution

a solution with pH above 7 and a lower H+ concentration: it has hight OH- concentraion

what is the normal arterial blood pH range

7.35-7.45

what urine pH range is listed

4.5-8.0; it can vary with activity, food and beverages, and medications

what is acidosis

lasma pH below 7.35

what is alkalosis

plasma pH above 7.45

what pH is neutral

7.0

what are examples of acidic body region/substances

stomach (about pH 2), urine/ urethra (about 4.5), skin (about 4.5)

what alkaline pH examples are listed

blood (7.35-7.45), bile (7.6-8.8), duodenum (7-8.5), pancreas (8.8), semen (7.2-8), amniotic fluid (7-7.4)

what is a buffer

a chemical that resists changes in pH by binding excess H+ or releasing H+ when concentraion falls

how quickly do chemical buffers respond

within seconds to minutes: they are the first respinders

what are some extracellular buffers

Bicarbonate (HCO-3), ammonia

what are intracellurlar buffers

proteins, phosphate, and hemoglobin (Hb)

what are the 3 main components of pH regulation

1) Buffers

2) kidneys maintaining H+

3) resporatory system regulating CO2

how quickly does respiratory compensation respond

minutes to hours: it is the second response

how quickly do the kidneys respind to pH imbalance

hours to days: they arethe last response but privide longer -term regulation

what is the bicarbonate buffer equation

CO2 + H2O → H2CO3 → HCO3- + H+

how is most CO2 carried in blood according to the slides

CO2 enters red blood cells, combines with water to form catbonic acid, which dissociates into H+ and bicarbonate; bicarbonate diffuses into the blood

what happens when excess H+ is present

the bocarbonate buffer reaction shifts left, helping bind H+ into carbonic acid

what happens when H+ is too low

the reacion shifits right, releasing H+ from the biffer system

does buffering remove H+ from the body

no, Buffers temporarily bind or Lock up H+; lungs and kidneys help remove or regulate it, when the slides also mentinoning long- term liver involvement

how can respiratory rate change the bicarbonate buffer equation

change CO2 echalation shifts the reaction and changes H+ concentraion

what is short term compensation for acid- base imbalance

adjesting ventilation rate

what is the normal plasma pH range

7.35-7.45

what does hypoventilation do to CO2 and H+

retains CO2, increasing carbonic acid and H+; pH decreases

what does hyperventilation do to CO2 and H+

exhales more CO2, lowering H+; pH increases

what is the respiratory center’s role in acid-base regulation

the medulla oblongata regulates breathing rate; respiratory centers alos invlolve the pons and reticular formation

where are central chemoreceptorts licated and what do they detect

in the CNS/ medulla; they detect cerebrospinal fluid pH changes and are sensitive to CO2

where are peripheral chemoreceptors located and what do they detect

carotid bodies and aortic arch; they detect O, CO2, H+

what is respiratiry acidosis

a low ph caused by elevated CO2, commonly due to hypoventilation

what PaCO2 level is descridbed as elecated in respiratory acidosis

above 45 mmHg

how is acute respiratory acidosis described

elecated PaCO2 with acidemia (pH below about 7.36)

how can chronic respiratory acidosis have a near-normal pH

they kidneys compensate by retaining/ reabsorbing bicarobate; the slides note elevated serum HCO3-

what cuases hypoventilation listed in the slides

drug use, aireay obstruction, sever lung disease (such as pneumothorax or pulmonary edma) or depression of the cental respiratory center

what symptoms of respiratory acidosis are listed

confustion, headacks, shortness of breath, fat heart rhythm, and arrhythmias

what is respiratory alkalosis

a high pH caused by excerssisve CO2 exhalation (hyperventilation)

what causes of respiratory alkalosis are listed

acute hypoxemia, pneumonia, interstitial lung disease, high altitude, anxiety, and pregnancy

what symptoms of respiratory alkalosis are listed

deep rapid breathing, lightheaddedness, dizziness, and agitaion

what is metabolic acidosis

a low pH associated with decreased bicarbonate ( the slides list HCO3- below 24 mmol/L), with respiratory compensation lowering CO2

what causes of metabolic acidosis are listed

chronic alcoholism, type 1 diabetes/ ketoacidosis, chronic renal failure, and lactic acidosis; a hight protein diet is also listed

what symptoms of metabolic acidosis are listed

heacdaches, drowsiness, CNS depression, hypotension, and gastrointestinal disorder

how does vomiting affect acid- base balance

loss of H+ in vomitus raises pH, causeing metablic alkalosis

how dies diarrhea affect acid -base balance

loss of bocarbonate is equivalent to gaining H+, lowering pH and causing metabolic acidosis

what is metabolic alkalosis

elevated pH associated wth decreased H+ and increased /retained bocarbonate

what causes of metabolic alkalosis are listed

vomiting, diuretic use, bicatbonate retention, and hyperaldosteronism

what are chloride- respinsive causes of metabolic alkalosis

low- chloride conditions such as vimiting, congenital chloride diarrhea, or diuretic use

what are chloride- resistant causes of metabolic alkalosis

high- chloride/ ongoing causes listed invlude bicarbonate retention and hyperaldosteronism

how do kidneys respond to acidosis

they secreat H+ into urine and reabsorb bicatbonate, helping raise pH

how do lungs compensate for metabolic acidosis

they reglexively hyperventilate, lowering CO2 and shifiting the buffer equation left to reduce H+

what does the glomerulus do with bicarbonate, according to th slides

it filters bicarbonate

what are 2 broad categories of acid-base imbalance

respiratory and metabolic; each can be acidosis or alkalosis

what does respiratory regulation control

the amount of CO2 present in plasma, which affects carbonic acid and H+

what is the key difference between respiratory and metabolic imbalances

respirartory imbalances begain with changes in CO2 ventilatin; metabolic imbalances begain whith changes in H+ or bocatbonate feom non-respiratory caises