Visão Geral do Sistema Digestivo: Órgãos, Funções e Processamento de Nutrientes

The digestive system converts food into absorbable nutrients through coordinated mechanical and chemical processes across specialized organs.

Alimentary Canal (GI Tract)

1. Mouth: Mastication, salivary amylase (starch), lingual lipase (fat).
2. Pharynx/Esophagus: Peristaltic transport; UES/LES sphincters.
3. Stomach: Churning, HCl (denature, sterilize), pepsin (protein), intrinsic factor (B₁₂). Chyme formation.
4. Small Intestine:
   • Duodenum: Bile, pancreatic juice (amylase, lipase, proteases), brush-border enzymes.
   • Jejunum/Ileum: Nutrient absorption (villi, microvilli → huge SA).
5. Large Intestine: Water/electrolyte absorption; microbiome (SCFA synthesis, vitamin K/B); stool formation.
6. Rectum/Anus: Defecation reflex (internal/external sphincters).

Accessory Organs

• Liver: Bile synthesis, metabolism, detox, storage.
• Gallbladder: Bile concentration/storage.
• Pancreas: Exocrine (enzymes, bicarbonate), endocrine (insulin, glucagon).

Regulation

ENS (100M neurons), hormones (gastrin, CCK, secretin, motilin, GIP), vagal/sympathetic input.

Integrated system ensures energy harvest and waste elimination.