Urinary System Flashcards
What renal process occurs at the renal corpuscle?
glomerular filtration
What are the three forces acting at the glomerulus that are responsible for the formation of filtrate?
1- Glomerular hydrostatic pressure 2- Colloid osmotic pressure (opposite force to glomerular hydrostatic pressure - sucking force due to proteins and RBC) - not as strong as 1 3- Capsular hydrostatic pressure
What are the forces in mmHg of the three pressures acting upon the glomerulus? 1- Glomerular hydrostatic pressure 2- Colloid osmotic pressure 3- Capsular hydrostatic pressure
1- Glomerular hydrostatic pressure - 55mmHg 2- Colloid osmotic pressure - 30mmHg 3- Capsular hydrostatic pressure - 15mmHg
Which of the three forces acting upon the glomerulus is equivalent to blood pressure?
Glomerular hydrostatic pressure
Which of the three forces acting upon the glomerulus is a consequence of proteins in the blood?
Colloid osmotic pressure
Which of the three forces acting upon the glomerulus is generated by fluids in the glomerular capsule?
Capsular hydrostatic pressure
These three forces acting at the glomerulus are responsible for the formation of filtrate. What is the not filtration pressure and what equation defines net filtration pressure (NFP)?
NFP is the pressure that is responsible for making the filtrate. This pressure needs to be a plus. The equation is Glomerular hydrostatic pressure - (Colloid osmotic pressure + Capsular hydrostatic pressure) NFP = 55 - (30+15) = 10
What is the definition of glomerular filtration rate?
The amount of filtrate by all nephrons in both kidneys. = 120 - 125mls per min
How does a decrease in blood pressure effect GFR, urine out put and Glomerular hydrostatic pressure?
Reduced glomerular hydrostatic pressure, reduced GFR and reduced urine.
How does an increased in blood pressure effect GFR, urine out put and Glomerular hydrostatic pressure?
increased glomerular hydrostatic pressure, increased GFR and increased urine.
If blood pressure is decreased how do the kidneys compensate for this?
Causes a reduction in GFR dilate afferent arteriole increase glomerular blood flow Increase Glomerular Hydrostatic pressure Increased GFR
If blood pressure is increased how do the kidneys compensate for this?
Causes an increase in GFR constrict afferent arteriole reduce glomerular blood flow reduce hydrostatic pressure reduce GFR
Explain the events that occur when there is a reduction in arterial pressure.
A reduction in arterial pressure –> inhibits baroreceptors –> increases sympathetic NS activity –> Kidneys produce Renin –> Renin turns angiotensinogen (produced in liver) to angiotensin I –> ACE (in the lungs) turns angiotensin I into angiotensin II –> angiotensin II acts on 4 areas - Causes Adrenal cortex to secrete aldosterone which in Na+ reabsorption –> increases H2O absorption - Increases ADH release by posterior pituitary –> increased water reabsorption - Increases thirst via hypothalamus –> increased water intake - Vasoconstriction increasing peripheral resistance All of these factors increase blood volume and therefore mean arterial pressure
Briefly describe the three processes involved in the production of urine.
• Glomerular Filtration - involves the transfer of soluble components such as water and waste from the blood into the glomerulus. • Tubular Reabsorption - involves the absorption of molecules, ions, and water that are necessary for the body to maintain homeostasis from the glomerular filtrate back into the blood. • Tubular Secretion - involves the transfer of hydrogen ions, creatinine, and drugs from the blood into the collecting duct.
What is the name of the vessel that feeds blood into the kidneys?
Cortical radiate artery
What is the name of the vessel that leads into the glomerular capsule?
Afferent arterioles
What part of the nephron is likely to be damaged by hypertension?
Glomerulus