Which of the following is an excitatory neurotransmitter in the central nervous system? MCQ with Answer and Explanation

Explanation:
Diapedesis (extravasation) is the migration of leukocytes through the endothelial junctions of capillaries into tissues in response to inflammation. Chemotaxis is the directed movement along a chemical gradient, phagocytosis is ingestion, opsonization is coating for phagocytosis. Both diapedesis and chemotaxis are part of the inflammatory response.

Explanation:
The liver continuously synthesizes bile, which is essential for fat emulsification. The pancreas acts as both an exocrine and endocrine gland; its Islets of Langerhans produce insulin and glucagon. The gall bladder only stores, concentrates, and releases bile; it does not produce any digestive enzymes. Thus, statements 1 and 2 are correct.

Explanation:
Reptiles generally have a three-chambered heart with two atria and one partially divided ventricle; crocodiles are an exception with a four-chambered heart. Amphibians have a three-chambered heart with two atria and one undivided ventricle. Mammals and birds have four-chambered hearts. This adaptation reflects their metabolic demands and evolutionary advancement.