Digestive System Chapter 24

Digestive System Why do you feel hungry? Because your brain receives a signal that your cells need ____________ ENERGY

Digestive System Digestive System - the organs that break down food so that the body can use it Parts of the digestive tract mouthpharynx esophagusstomach small intestinelarge intestine rectumanus

Parts of the Digestive System

Digestion Digestion - the process of breaking down food so it can pass through the digestive tract 2 types of digestion 1.mechanical digestion - crushing/mashing of food 2.chemical digestion - changing food into small particles to be absorb by the bloodstream

Digestion teeth - breaks down food to make it easier to digest (help mix food with saliva)

Digestion saliva - contains enzymes that begins chemical digestion (saliva changes carbohydrates into simple sugars) esophagus - squeezes the food and moves it into the stomach

Digestion Stomach - –squeezes the food with muscular contractions (mechanical digestion) –Adds enzymes and acid to food (chemical digestion) Leaving the stomach the chyme is mixed with fluids from the liver and pancreas

Digestion small intestine - where the chyme is absorbed into the bloodstream by villi (small intestine is where most digestion takes place) liver - largest organ in the body –makes bile to break up fat –stores nutrients –breaks down toxins

Digestion gallbladder - bile is squeezed and moved into the small intestine (mechanical)

Digestion large intestine - particles too large to be absorbed into the blood are pushed into the large intestine

Urinary System Urinary system - organs that remove waste products from your blood

How the kidney filters blood 1.Blood enters the kidney (by a large artery) 2.Tiny blood vessels bring blood to the nephrons (nephrons remove wastes from the blood) 3.As the blood flows water and nutrients are returned to the blood 4.Concentrated wastes from urine are passed to the bladder

Urinary Problems Bacterial infections - bacteria gets into the bladder and cause painful infections Kidney stones - salts and wastes collect inside the kidneys, causes stones Kidney disease - damage to nephrons can affect normal kidney function causing kidney disease

The End