Ultrafiltration Flashcards
1
Q
What is ultrafiltration?
A
- Filtering out of substances out of the blood at the molecular level
2
Q
How does ultrafiltration work?
A
- High hydrostatic pressure
- afferent arterioles is wider than the efferent arterioles
- small molecules are forced out into the Bowsman’s capsule to form the filtrate
- Large molecules do not fit through the gaps
- Gaps in capillary walls
- Gaps in the capillary membrane
- Gaps in the podocytes
- e.g. Red Blood cells, proteins
3
Q
What 3 layers do molecules have to pas through in order to move from the blood into the renal filtrate?
A
- the walls of the capillaries in the glomerulus
- the basement membrane of the renal capsule
- special cells called podocytes
4
Q
What substances would stay in the blood?
A
- Red Blood cells
- White Blood Cells
- platelets
- most of the plasma proteins
5
Q
What substances would leave the blood?
A
- water
- urea
- glucose
- amino acids
- inorganic ions
- sometimes hormones
6
Q
What is the basement membrane made out of?
A
- collagen and glycoproteins
7
Q
What does the basement membrane do?
A
- Most of the molecules found in the blood plasma are small enough to pass through the basement membrane
8
Q
What is the structure of podocytes?
A
- Additional layer
- They have extensions called pedicles that wrap around capillaries, forming slits
9
Q
What do podocytes do?
A
- They ensure that any blood cells or large proteins that did get across the basement membranes do not enter the filtrate
10
Q
What is a glomerular Filtration Rate?
A
- The volume of blood filtered through the kidneys in a given time.
- It gives an idea of how well the kidneys are working.
