Digestive system

Ingestion: food taken into mouth Digestion: food broken down through chemical reactions, where it’s converted into smaller molecular forms Absorption: (NUTRIENTS ABSORBED) small molecular forms are absorbed through the cells of your digestive system and pass into nearby blood or lymphatic vessels Transport: your circulatory system delivers the small molecular nutrients to your body cells Egestion: waste is stored and expelled.

cellulose as they dont have the cellulase enzyme

Digestive enzymes are added as the food moves down the digestive system Enzymes act as catalysts & Lower the activation energy Reactions within the digestive system are all hydrolysis reactions

Humans have a body temp. Of 37oC as this is a good temperature for good molecular movement + for the enzymes to work in their optimum environment

found in mouth, pH 7, breaks down starch to sugar (to maltose and then further to glucose

found in stomach, pH 1-2, breaks down proteins

found in pancreas + small intestine, ph 8, breaks down fats

found in pancreas + small intestine, ph 8, completes breakdown of sugar and proteins

using the teeth, mechanical digestion occurs here, as the food is ground up. The salivary glands also release enzymes (amylase, pH 7) to break down starch into sugar (maltose, which is then ultimately broken down into glucose) and moisten the food

Food travels down the oesophagus tract through peristalsis

Food is turned into chyme through acids and enzymes (churning) Chemical and mechanical digestion Pepsin breaks down proteins into amino acids (pH 2-3)

Toxins are filtered from the blood Bile is produced (BILE: increases absorption of fats, by breaking them into small droplets that the enzyme lipase can attack)

Bile is stored here and eventually released into the small intestine

Absorption of nutrients and minerals, and continuation of food digestion

Recycles water and mineral salts back into bloodstream via diffusion Excretes the undigested material Enzyme maltase catalyses the hydrolysis of maltose into glucose

Storage of faeces

Storage of faeces

• produces insulin and glucagon hormones lipase, amylase and endopeptidase enzyme production thats released into the small intestine (pancreatic juice)