Different types of respiratory organs like gills,book gills,book lungs and trachea are present in

The spiracle participates in which of the following processes?

How does a tree trunk exchange gases with the environment although it lacks stomata?

Among vertebrates,...$A$... use gills whereas reptiles,birds and mammals respire through the ...$B$... Amphibians like frogs can respire through ...$C$... also. Mammals have a well adapted respiratory system. Select appropriate choice for the blanks $A, B$ and $C$ to complete the given $NCERT$ statement.

Insects like cockroach and silverfish have which of the following respiratory pigments?

In crustaceans,respiration occurs through ..........