TS EAMCET Medical 09 AUG 2021 Shift 1 Paper

Study the following and pick up the correct statements.
I) Contraction of dorsoventral muscles depress the wings in cockroach.
II) Stomodeal valve lies between gizzard and mesenteron in cockroach.
III) In cockroach, the spiracles are holopneustic type.
IV) Opening and closing of spiracles is influenced by 02 tension in haemolymph and CO2 tension in tracheae