At this page you will find Multiple Choice Questions or MCQs for all Chapters of Biology Class 11. _________ is one of the most important metabolic activities of all organism? One polypeptide chain with iron containing ring structure is myoglobin The main tracheal trunk in cockroach communicates with exterior by? In a hot and dry day level of __________ inside the leaf rises? Lungs are covered with double layered thin membranous sacs called ___________? The cork tissue has special pores called _________, involved in gaseous exchange.