Respiratory pigment in cockroach is

The blood of cockroach contains no respiratory pigment. It means that

....... is function of nephrocytes and urecose gland.

Select the correct sequence of organs in the alimentary canal of cockroach starting from mouth

Which of the following features is not present in Periplaneta americana?

Which type of mouthparts is present on the lateral side of the pre-oral cavity in cockroach?