Nutrition in Humans

What this topic covers

• •Four separate stages: ingestion, digestion, absorption, assimilation, egestion
• •Peristalsis pushes food along the gut
• •The mouth and salivary glands start digestion mechanically and chemically
• •The stomach churns food and starts protein digestion
• •The duodenum receives secretions from the pancreas, liver and gall bladder
• •Digestive enzymes each break down one type of substrate
• •Bile is not an enzyme, it physically breaks fat into droplets
• •The ileum's villi are built for absorbing digested food
• •The hepatic portal vein sends absorbed nutrients straight to the liver
• •The liver processes nutrients and breaks down harmful substances
• •The colon, rectum and anus complete the process