Control of Blood Water Potential (WIP) Flashcards
What is osmoregulation?
The homeostatic control of the water potential and salt content of the blood. This in turn helps maintain a fairly constant water potential of blood plasma and tissue fluid.
What is the key function of the nephron?
To carry out osmoregulation.
What are the stages of nephron carrying out osmoregulation?
- Formation of glomerular filtrate
- Selective reabsorption of glucose and water by the proximal convoluted tubule
- Maintenance of a gradient of sodium ions in the medulla by the loop of Henle
- Reabsorption of water by the distal convoluted tubules and collecting ducts
What is the renal pelvis?
A funnel-shaped cavity that collects urine into the ureter.
What is the ureter?
A tube that carries urine to the bladder.
What does the renal artery do?
Supplies the kidney with blood from the heart via the aorta.
What does the renal vein do?
Returns blood to the heart via the vena cava.
What is the fibrous capsule?
An outer membrane that protects the kidney.
What is the cortex?
A lighter coloured outer region made up of renal (Bowman’s) capsules, convoluted tubules of blood vessels.
What is the medulla?
A darker coloured inner region made up of loops of Henle, collecting ducts and blood vessels.
What happens during ultrafiltration?
Removes water, urea, glucose, amino acids + mineral ions from the blood. It does not removed RBC’s, WBC’s. platelets or large proteins.
Where does ultrafiltration occur?
The Bowman’s capsule.
What are the barriers to glomerular filtrate formation?
- Capillary endothelial cells
- Connective tissue
- Epithelial cells of the renal cells
- The hydrostatic pressure from renal capsule fluid
- The less negative water potential of the blood in the glomerulus
What are podocytes?
Specialised cells with spaces between them to allow filtrate to pass through. They make up the inner layer of the renal capsule.
