The 'Founder Effect' is a cause of: MCQ with Answer and Explanation

Explanation:
Peyer's patches are organized lymphoid follicles (aggregated lymphoid nodules) located in the mucosa and submucosa of the small intestine, most abundantly in the ileum (the distal part). They are a crucial component of the gut-associated lymphoid tissue (GALT) and play a vital role in monitoring intestinal bacteria populations, preventing the growth of pathogenic bacteria, and training the immune system to recognize antigens.

Explanation:
Lactase is a brush border enzyme of the small intestine that hydrolyzes the disaccharide lactose (milk sugar) into its constituent monosaccharides, glucose and galactose. Maltase acts on maltose, sucrase on sucrose, and amylase on starch. Lactose intolerance results from lactase deficiency, causing gastrointestinal symptoms after dairy consumption.

Explanation:
Osteomalacia is softening of bones in adults due to vitamin D deficiency, leading to bone pain and muscle weakness. Rickets is the childhood equivalent, affecting growth plates. Scurvy is vitamin C deficiency, kwashiorkor is protein deficiency. Vitamin D is essential for calcium absorption and bone mineralization.