The branch of biology concerned with the study of insects is: MCQ with Answer and Explanation

Explanation:
The medulla oblongata, part of the brainstem, contains vital centers that control respiration, heart rate, and blood pressure. It also regulates reflex actions like coughing, swallowing, and vomiting. The cerebrum is for voluntary actions and thinking, cerebellum for coordination, and hypothalamus for homeostasis and endocrine control.

Explanation:
Vitamin K is a cofactor for γ-glutamyl carboxylase, which modifies glutamate residues in clotting factors, enabling calcium binding and coagulation.

Explanation:
Enterokinase (enteropeptidase) is secreted by the intestinal mucosa and activates the pancreatic proenzyme trypsinogen to trypsin, which then activates other zymogens. Pepsin is active in the stomach, renin is a milk-curdling enzyme (chymosin), carboxypeptidase is a pancreatic protease. This cascade ensures that protein-digesting enzymes are activated only in the appropriate location to prevent autodigestion.