In what form do the cockroaches excrete out their nitrogenous wastes?

Frogs show sexual dimorphism. True or false?

Which of the following is not a type of simple epithelial tissue?

What does the question mark represent in the following diagram?

What material is the exoskeleton of the cockroach made of?

Earthworm is an invertebrate.

Which of these is characteristic of hindwings of a cockroach?

At which of these segments does the nerve cord of the earthworm divide into two parts?