Question

1. the effective glomerular filtration pressure is equal to (c)

a. glomerular capillary pressure + plasma colloid osmotic pressure +bowmans capsule pressure
b. glomerular capillary pressure - plasma colloid osmotic pressure +bowmans capsule pressure
c. glomerular capillary pressure - plasma colloid osmotic pressure -bowmans capsule pressure
d. glomerular capillary pressure + plasma colloid osmotic pressure -bowmans capsule pressure

Explanation:

To determine the effective glomerular filtration pressure (GFP), we use the formula: \( \text{GFP} = \text{Glomerular capillary pressure} - \text{Plasma colloid osmotic pressure} - \text{Bowman's capsule pressure} \)? Wait, no—correction: The correct formula is \( \text{Effective Glomerular Filtration Pressure (eGFP)} = \text{Glomerular Capillary Hydrostatic Pressure (GHP)} - \text{Plasma Colloid Osmotic Pressure (COP)} - \text{Bowman's Capsule Hydrostatic Pressure (CHP)} \)? Wait, no, let's recall: The forces promoting filtration are GHP (glomerular capillary hydrostatic pressure, pushing fluid out). The forces opposing filtration are Plasma Colloid Osmotic Pressure (COP, pulling fluid back into capillaries due to proteins) and Bowman's Capsule Hydrostatic Pressure (CHP, pushing fluid back from capsule). So \( \text{eGFP} = \text{GHP} - \text{COP} - \text{CHP} \)? Wait, but looking at the options:

Option C: Glomerular capillary pressure - Plasma colloid osmotic pressure - Bowman's capsule pressure? Wait, no, the option C is written as "Glomerular capillary pressure - Plasma colloid osmotic pressure - Bowman's capsule pressure"? Wait, the option C in the image: "C. Glomerular capillary pressure - Plasma colloid osmotic pressure - Bowman's capsule pressure"? Wait, no, the user's image shows:

Wait the user's image:

Option C: "Glomerular capillary pressure - Plasma colloid osmotic pressure - Bowman's capsule pressure"? Wait no, let's re-express the options:

A. Glomerular capillary pressure + Plasma colloid osmotic pressure + Bowman’s capsule pressure → Sum of all, which can't be (since two are opposing)
B. Glomerular capillary pressure - Plasma colloid osmotic pressure + Bowman’s capsule pressure → Subtract COP (opposing) but add CHP (opposing), which is wrong (CHP opposes, so should subtract)
C. Glomerular capillary pressure - Plasma colloid osmotic pressure - Bowman’s capsule pressure → This matches the formula: GHP (promoting) minus COP (opposing) minus CHP (opposing)
D. Glomerular capillary pressure + Plasma colloid osmotic pressure - Bowman’s capsule pressure → Adding COP (which opposes) is wrong.

So the correct formula is \( \text{Effective GFR pressure} = \text{Glomerular Capillary Pressure} - \text{Plasma Colloid Osmotic Pressure} - \text{Bowman's Capsule Pressure} \), which corresponds to option C.

Answer:

C. Glomerular capillary pressure - Plasma colloid osmotic pressure - Bowman's capsule pressure