In a cockroach,the grinding of food takes place in the ........?

Which of the following structures originates from the ectoderm?

Phallic organs in cockroach are related to

Which of the following statement$(s)$ is/are correct regarding the excretory system of a cockroach?
$(i)$ Excretion is performed by Malpighian tubules.
$(ii)$ They absorb nitrogenous waste products and convert them into uric acid,which is excreted out through the hindgut.
$(iii)$ In addition,fat body,nephrocytes,and urecose glands also help in excretion.

Open circulatory system is not a physiological hindrance in a $Cockroach$ because

In female cockroaches,the $Gynovalvular$ plates are modifications of which of the following?