Kidney Physiology Flashcards
3 main functions of the kidney include…
Excretory
Endocrine
Metabolic
The excretory function of the kidneys includes these 2 aspects…
Regulation of fluid, electrolytes, and acid-base
Removal of metabolic waste products + foreign chemicals from blood for urinary excretion
The excretory function of the kidney is accomplished via these three physiological mechanisms:
Filtration
Reabsorption
Secretion
In filtration, blood enters the glomerulus through the _____
Afferent arteriole
Glomerular filtration is when…
Blood gets filtered via hydrostatic pressure through capillaries that form the glomerulus, into the Bowman capsule
Filtrate is mainly composed of…
in a healthy kidney
Fluids, electrolytes, and small molecules
Glucose, amino acids, urea, uric acid, some protein
Blood leaves the kidney through the ____
Efferent arteriole
Reabsorption describes…
The movement of substances OUT of renal tubules back INTO blood capillaries
Filtrate back into blood
Reabsorption is an important part of the excretory process, because it…
Prevents substances needed by the body, from being los in the urine
Water, salt, bicarb, urea, amino acids, glucose
Secretion describes…
Substances moving OUT of blood and INTO tubules, mixing with filtrate and convert to urine
Include H+, K+, uric acid, certain drugs
Substances are secreted by either…
Active transport mechanism
Diffusion across membranes
The body maintains pH within…
7.35 - 7.45 via H+ regulation
Two ways of regulating H+ concentration includes these two systems
Lungs and Kidney
The kidney impacts H+ concentration by these factors…
Hydrogen ion excretion
Bicarbonate reabsorption
Phosphate + ammonia buffer systems
In response to acidosis, the kidneys will…
Reabsorb all filtered bicarbonate, and produce new bicarbonate
Metabolic acidosis; paCO2 is normal
