Which of the following blood cells is responsible for the immune response by producing antibodies? MCQ with Answer and Explanation

Explanation:
Pancreatic juice contains inactive enzymes like trypsinogen, chymotrypsinogen, and procarboxypeptidase. When trypsinogen enters the small intestine, it is activated into trypsin by the enzyme enterokinase (secreted by the intestinal mucosa). Trypsin then digests proteins into smaller peptides. Pancreatic amylase digests carbohydrates, and lipase digests fats.

Explanation:
Kidneys are retroperitoneal, not in the abdominal cavity proper. They produce renin, and filter ~180 L/day (GFR ~125 mL/min). So 1 is incorrect.

Explanation:
The spleen is the largest organ in the lymphatic system. It plays a vital role in immune function by filtering blood, producing lymphocytes, and removing old or damaged red blood cells and platelets. The thymus is crucial for T-cell maturation but is largest in childhood and shrinks with age. Tonsils and Peyer's patches are smaller, localized lymphoid tissues. The spleen acts as a major blood filter and immune response center.