QuestionSBA
QuestionChoice
Na+ residues within the basolateral membrane which will facilitate a low intracellular Na+ concentration, creating a favourable electrochemical gradient for Na+  reabsorption by the Na+/H+ antiporter.
10009559
e
The Na+ pump in the apical membrane creates a low intracellular Na+ concentration and creates a favourable electrochemical gradient
QuestionChoice
The PCT is the primary site of reabsorption of HCO3- within the kidney and it is carried out via an indirect method involving carbonic anhydrase since the apical membrane is impermeable to HCO3-
10009556
b
10% of the HCO3-  present within the filtrate is reabsorbed in the PCT via the indirect method involving Carbonic Anhydrase
QuestionChoice
Correct Answer
10009555
a
90% of the HCO3- present within the filtrate is reabsorbed in the PCT via the indirect method involving Carbonic Anhydrase
QuestionChoice
PCT has a high permeability to water. Water reabsorption is facilitated paracellularly across tight junctions and transcellular via water channels. There is also the presence of an Osmotic pressure gradient maintained by Na+ reabsorption, and increased oncotic pressure in peritubular capillaries.
10009557
c
PCT is majorly impermeable towards the water in the filtrate, and the reabsorption of water is prevented via a lack of paracellular tight junctions and a lack of osmotic gradient
QuestionChoice
67% of K+ is reabsorbed in the PCT, however, this is via paracellular transport as the primary method of reabsorption. There is also an active transport of K+ inwards via Na+/K+ ATPase
10009558
d
67% of K+ is reabsorbed in the PCT due to passive transport involved in the K+/Cl- ATPase
Concept
Chapter
2693
5352
PCT
Topic
263
Renal
14459
The Proximal Convoluted Tubule (PCT) is one of the primary sites of reabsorption for the kidney.

From the answers below, select which is the **most** correct in terms of percentage reabsorption in the PCT.
a