How many of the following chordates have flame cells as excretory organ. Planaria, Ascaris, Amphioxus, Tapeworm, Nereis, Scoliodon.
 

Graph depicts the concentration of enzymes involved in urea synthesis in a developing tadpole. It indicates a transition from

The diagrams show vertical sections of kidneys of coypu, brown rate and kangaroo rat, showing the relative size of cortex and medulla. Coypu are found in freshwater and never short of water to drink. Brown rats are able to go some days without drinking at all. Which kidney belongs to which animal?

Select the correct order of osmolarity changes in filtrate w.r.t. plasma:

Bowman's capsule $\to \mathrm{PCT}\to$ Thin part of descending limb of the loop of Henle $\to$ Thin part of ascending limb of the loop of Henle $\to \mathrm{DCT}\to$ End of collecting duct