Renal system and homeostasis Flashcards
Principal extracellular ions are…
sodium, potassium, bicarbonate
principal intracellular ions are..
Potassium, magnesium, phosphate
What is Osmolality
-Water and Sodium balance
-Controlled by 2 processes:
1) Osmoregulation = Water control.
2) Volume regulation = Sodium control.
Explain the two different types of disturbances of H2O balance
Dehydration: Excess H2O loss cause Diarrhea or vomiting and Hypovolemia (decrease in plasma volume and loss of blood pressure)
Overhydration:
How is Blood pH regulated
kidneys + resperation
how do kidneys help regulate blood ph
Kidneys help regulate pH by:
-Reabsorbing or producing bicarbonate (a base) to neutralize excess acid.
-Excreting excess bicarbonate when there’s too much base in the blood.
-Excreting acidic metabolic waste products (like hydrogen ions) to lower acidity.
how does Respiratory system help regulate blood ph
Respitory system controls the amount of dissolved carbon dioxide in the blood. This happens quickly through changes in breathing rate—faster breathing removes more carbon dioxide, which can lower acid levels.
What happens in Metabolic acidosis
the body produces too much acid or can’t get rid of it properly. This overwhelms the body’s ability to buffer (neutralize) the acid.
How does the body try to compensate with Metabolic acidosis
The body tries to neutralize excess acid using bicarbonate (a base).
As bicarbonate is used up to neutralize the acid, its levels in the blood fall.
-The body also tries to fix this by hyperventilating (breathing fast) to lower CO2 and reduce acidity.
What happens in Respiratory Acidosis:
happens when the lungs can’t exhale enough CO2 (carbon dioxide), which causes CO2 to build up in the blood..
The excess CO2 reacts with water to form carbonic acid (H2CO3), increasing the acidic level of the blood.
What happens with Respiratory Alkalosis:
- when you hyperventelate you loose alot of CO2 which in return causes loss in carbonic acid leading to excess bicarbonate
List the 3 main functions of the Kidneys
1)Excrete waste products:
Removes end products of metabolism like urea , uric acid, and fatty acids .
2)Controls minerals, electrolytes, acids (pH), and water in the body.
Excretes excess and conserves what’s needed to maintain balance.
Produce hormones:
3) Erythropoietin: Stimulates red blood cell production in the bone marrow.
Renin: Helps regulate blood pressure.
Thrombopoietin: Involved in platelet production.
What are the layers of the Glomerulus
1)Inner layer: Fenestrated capillaries (tiny holes) let some things through.
2)Middle layer: Basement membrane, like a filter that keeps out large molecules.
3)Outer layer: Capillary endothelial cells with special foot processes and filtration slits that further help with filtering.
What are Mesangial cells
These cells help hold the capillaries together, contract to adjust blood flow, and clean up by eating debris.
What is Control of Glomerular Filtration Rate (GFR):
is the rate at which the kidneys filter blood.
What are Key Factors Controlling GFR:
1)Porosity and length of glomerular capillaries: The more pores or openings in the capillaries, the easier it is to filter blood.
2)Fluid and oncotic pressure: The pressure inside the capillaries versus the pressure outside affects how much fluid is filtered.
How does the Kidney Controls GFR
flood flow resistance: The kidneys adjust the afferent arteriole (bringing blood in) to control how much blood flows into the glomerulus. This happens by dilating (widening) or contracting the blood vessels.
2)The macula densa (in the loop of Henle) senses the pressure and helps adjust the blood flow and GFR accordingly.
what is Hyponatremia
Low sodium in the blood, causing cells to swell (water moves into cells).
what is Hypernatremia
High sodium in the blood, causing cells to shrink (water moves out of cells).
What happens when blood becomes too concentrated (high osmolality)
the brain (hypothalamus) senses this and triggers:
Thirst (to drink more water).
Release of antidiuretic hormone (ADH) from the posterior pituitary gland, which makes the kidneys retain water (producing less urine) and helps lower sodium levels.
