The following diagram represents a mammalian kidney tubule (nephron) and its blood supply.

Parts indicated by the guidelines 1 to 8 are as follows:
1. Afferent arteriole from renal artery
2. efferent arteriole
3. Bowman’s capsule
4. Glomerulus;
5. Proximal convoluted tubule with blood capillaries;
6. Distal convoluted tubule with blood capillaries;
7. collecting tubule;
8. U-shaped loop of Henle
Study the diagram and answer the question that follow:
Where does ultrafiltration take place?