Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
77 Cards in this Set
- Front
- Back
|
What does Estrogen do wih NaCl?
|
Increases reabsorption.
Why girls retain water during menstrual cycles and pregnancy. |
|
|
What does progesterone do with Na+?
|
Blocks aldosterone, and lowers reabsorption of Na+.
|
|
|
What happens when the Baroreceptors alert the brain of increases in Blood volume and blood pressure? 4 things
|
1. SNS impulses to kidneys decline
2. Afferent arterioles dilate 3. GFR increases 4. Na+ and water output increase |
|
|
What is the importance of potassium?
|
Affects RMP in neurons and muscle cells
Especially in cardiac muscle |
|
|
What happens when ECF K goes up?
|
RMP goes down.
Depolarization Reduced excitability |
|
|
What happens when ECF potassium goes down?
|
Hyperpolarization and nonresponsiveness
|
|
|
What happens when hydrogen ions shifts in and out of the cells regarded to potassium?
|
Leads to corresponding shifts in K+ in opposite direction to maintain cation balance
Interferes with activity of excitable cells |
|
|
How is K+ balance controlled in cortical collecting ducts?
|
By changing amount of K+ secreted into filtrate
|
|
|
What happens when K+ content of ECF is high?
|
It favors principal cell secretion of K+
|
|
|
What happens when K+ levels are low?
|
Type A intercalated cells reabsorb some K+ left in filtrate
|
|
|
What influences does Aldosterone have? 3 things
|
1. Stimulates K+ secretion and Na+ reabsorption by principal cells
In the adrenal cortex 2. release of aldosterone 3. Potassium secretion |
|
|
What is calcium, Ca2+ important for? 4 things
|
1. Neuromuscular excitablity
2. Blood clotting 3. Cell membrane permeability 4. Secretory activities |
|
|
What is hypocalcemia and what does it do?
|
Low calcium levels
Excitability and muscle tetany |
|
|
What is hypercalcemia and what does it do?
|
High calcium levels
inhibits neurons and muscle cells, may cause heart arrhythmias |
|
|
What is the calcium balance controlled by? 2 things
|
Parathyroid hormone and calcitonin
|
|
|
What is largest reservoir of Ca2+ and phosphates?
|
Bones
|
|
|
What does PTH promote, and what does it target in our body?
|
Promotes increase in calcium levels and targets bones, kidneys, and small intestine.
|
|
|
Calcium reabsorption and what excretion goes hand in hand?
|
PO4 or phosphate
|
|
|
What is the major anion in ECF?
|
Chlorine, or Cl-
|
|
|
What does chlorine do in the blood?
|
Maintains osmotic pressure of blood
|
|
|
What is acidosis?
|
Fewer Cl- reabsorbed
|
|
|
What does pH affect?
|
All functional proteins and biochemical reactions
|
|
|
What is your normal pH in arterial blood?
|
7.4
|
|
|
What is your Normal pH in Venous blood and IF fluid?
|
7.35
|
|
|
What is your normal pH of ICF?
|
7.0
|
|
|
What is Alkalosis or alkalemia?
|
Arterial blood having a higher pH than 7.45
|
|
|
What is acidosis or acidemia?
|
Arterial pH being less then 7.35
|
|
|
Where do most of our H+ come from? Produced by? 4 things
|
1. Phosphoric acid
2. Lactic acid 3. Fatty acids and ketone 4. H+ liberated when CO2 converted to HC03- in blood |
|
|
What 3 things is H+ ions regulated by?
|
1. Chemical buffer systems - rapid
2. Brain stem respiratory center - 1 to 3 minutes 3. Renal mechanisms - most potent from hours to days to effect pH changes |
|
|
Define a strong acid.
|
Dissociates completely in H20
|
|
|
Define a week acid.
|
Dissociates partially in H20; effficient at preventing pH changes
|
|
|
Define strong bases.
|
Dissociate easily in water; ties up H+.
|
|
|
Define a weak base.
|
Accept H+ more slowly
|
|
|
What is the chemical buffer system basically?
|
System of 1 or more compounds that act to resist pH changes
|
|
|
What 3 things make up the Chemical buffer system?
|
1. Bicarbonate buffer system
2. Phosphate buffer system 3. Protein buffer system |
|
|
What happens in the Bicarbone buffer system?
|
Mixture of H2CO3 and salts of HCO3.
Buffers ICF and ECF |
|
|
What is the only important ECF buffer?
|
The bicarbonate buffer system
|
|
|
What happens when a strong acid is added to the Bicarbonate buffer system?
|
HC03 ties up H+ and forms H2CO3
|
|
|
What is HCO3 concentration regulated by?
|
Kidneys
|
|
|
What happens when a strong base is added to the Bicarbonate buffer system? 4 things
|
1. H2CO3 dissociates and donates H+
2. H+ ties up the base 3. pH rises only slightly 4. H2CO3 supply is almost limitless - is subject to respiratory controls |
|
|
What does the Phosphate buffer system do?
|
Action nearly identical to bicarbonate buffer system
Effective buffer in urine and ICF |
|
|
What is found in the Protein buffer system?
|
Intracellular proteins most plentiful and powerful buffers
plasma proteins also important |
|
|
What are protein molecules?
|
Amphoteric
|
|
|
What does amphoteric mean?
|
Can function as both a weak acid and a weak base
|
|
|
What happens in the protein buffer system when pH rises?
|
Organic acid or carboxyl(COOH) groups release H+
|
|
|
What happens in the protein buffer system when pH falls?
|
NH2 groups bind H+
|
|
|
What is our physiological buffer system?
|
Respiratory and renal systems
- Act more slowly - Have more capacity |
|
|
What happens when CO2 unloads, shifting to the left?
|
H+ incorporated into H2)
|
|
|
What happens when CO2 loading reaction shifts to the right?
|
H+ buffered by proteins
|
|
|
What is Hypercapnia?
|
Too much CO2
|
|
|
What does Hypercapnia activate?
|
Medullary chemoreceptors
|
|
|
What does rising plasma H+ activate and what does it do?
|
Peripheral chemoreceptors
- More CO2 is removed from blood - H+ concentration reduced |
|
|
What does Alkalosis do with breathing?
|
Depresses respiratory center for
1. Respiratory rate/depth decrease 2. H+ concentration increases |
|
|
What does hypoventilation lead to?
|
Respiratory acidosis
|
|
|
What does hyperventilation lead to?
|
Respiratory alkalosis
|
|
|
How do lungs eliminate carbonic acid?
|
By eliminating CO2.
|
|
|
What do the kidneys get rid of?
|
Fixed metabolic acids -
Phsphoric Uric lactic Ketones |
|
|
What do the kidneys help prevent by eliminating the acids that it does?
|
It prevent metabolic acidosis
|
|
|
What are the 2 most important renal mechanisms?
|
1. Conserving or generating new HC03-
2. Excreting HCO3- |
|
|
What happens when 1 HCO3- is generated or reabsorbed?
|
Lose 1 H+
|
|
|
What image should we look at to understand all this crap?
|
26.2
|
|
|
List the 4 steps in reabsorption of bicarbonate.
|
1. CO2 + water in PCT cells = H2CO3
2. H2CO3 dissociates 3. H+ secreted, HCO3- is reabsorbed into capillary 4. Secreted H+ plus HCO3- = H2CO3 in filtrate generates CO2 and H20 |
|
|
What 2 mechanisms are there to generate new Bicarbonate ions?
|
PCT
Type A intercalated cells |
|
|
How is dietary H+ balanced?
|
By generating new HCO3-
|
|
|
How is H+ excreted and where?
|
Intercalated cells actively secrete H+ into urine buffered by phosphates and execreted
|
|
|
What happens to new HCO3?
|
Moves into interstitial space via a cotransport system and then moves passively into peritubular capillary blood.
|
|
|
Why is there ammonia in urine?
|
Involves metabolism of glutamine in PCT cells
|
|
|
How is ammonia added to urine?
|
Each glutamine produces 2 NH4+ and 2 new HCO3-
HCO3- moves to blood and NH4+ is excreted in urine. |
|
|
What happens when the body is in alkalosis in the type B intercalated cells? 2 things
|
1. Secrete HCO3-
2. Reclaim H+ and acidify blood |
|
|
What is special about the Bicarbone IOn Secretion?
|
The mechanism is opposite of bicarbone ion reabsorption process by type A intercalated cells
|
|
|
What are the two different types of abnormalities of acid-base balance?
|
Respiratory and metabolic acidosis or alkalosis
|
|
|
What is the most important indicator of adequacy of respiratory function?
|
PCO2 level that is normally 35-45 mm Hg
|
|
|
What happens when PCO2 > 45 mm Hg
|
Respiratory acidosis
1. most common cause of imbalances 2. decreased ventilation or gas exchange 3. Blood pH falls - PCO2 rises |
|
|
What happens when PCO2 is below 35 mm Hg?
|
Respiratory alkalosis
Common result of hyperventilation |
|
|
What basically is metabolic acidosis or alkalosis and how is it caused?
|
It's any pH imbalance not caused by abnormal blood cO2 levels
|
|
|
How is metabolic misfunction indicated by?
|
Abnormal HCO3- levels
|
|
|
What are causes of metabolic acidosis? 3 things
|
1. Too much alcohol - Acetic acid
2. Excessive loss of HCO3- ( eg. persistent diarrhea) 3. Accumulation of lactic acid, shock, ketosis in diabetic crisis, starvation, and kidney failure |
