Life Science 3.1 : The Digestive System
Upcoming SlideShare
Loading in...5

Life Science 3.1 : The Digestive System






Total Views
Slideshare-icon Views on SlideShare
Embed Views



1 Embed 17 17



Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.


11 of 1

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
Post Comment
Edit your comment

    Life Science 3.1 : The Digestive System Life Science 3.1 : The Digestive System Presentation Transcript

    • Life Science Chapter 3
      The Digestive and Urinary Systems
    • Life Science 3.1
      The Digestive System
    • Objective:
      Compare mechanical digestion with chemical digestion.
      Describe the parts and functions of the digestive system.
    • Digestive System at a Glance
      Digestive system
      Group of organs that break down food so that it can be used by the body.
      Food passes through the digestive tract.
      The digestive tract includes
      your mouth, pharynx, esophagus, stomach, small intestine, large intestine, rectum, and anus.
      The liver, gallbladder, pancreas, and salivary glands are also part of the digestive system.
    • Breaking Down Food
      Mechanical digestion
      Breaking, crushing, and mashing of food.
      Chemical digestion
      Large molecules are broken down into nutrients with the aid of enzymes.
    • Digestion Begins in the Mouth
      With the help of strong jaw muscles, teeth break and grind food.
      Contains an enzyme that begins the chemical digestion of carbohydrates.
    • Leaving the Mouth
      Once the food has been reduced to a soft mush, the tongue pushes it into the throat, which leads to a long, straight tube called the esophagus.
    • Stomach
      Muscular, saclike, digestive organ attached to the lower end of the esophagus.
      Tiny glands in the stomach
      Produce enzymes and acid to break food down into nutrients.
      After a few hours of combined mechanical and chemical digestion,
      Food leaves your stomach as a soupy mixture called chyme.
      The Harsh Environment of the Stomach
    • The Pancreas and Small Intestine
      Organ located between the stomach and small intestine.
      Makes fluids that protect the small intestine from the acid in chyme.
      Small Intestine
      Muscular tube that is about 2.5 cm in diameter and about 6 m long.
      Nutrients are absorbed into the bloodstream through fingerlike projections called villi.
    • The Liver and the Gallbladder
      Large, reddish brown organ that helps with digestion by making bileto break up fat.
      Stores excess nutrients until the body is ready to absorb them into the bloodstream.
      Breaks down toxins.
      Saclike organ that stores bile
      Squeezes the bile into the small intestine.
      Breaks large fat droplets into smaller ones.
    • The End of the Line
      Large intestine
      Wider and shorter portion of the intestine that removes water from mostly digested food and that turns the waste into semisolid feces, or stool.
      Feces are stored in the rectum until they can be expelled.
      About 1.5 m long, 7.5 cm diameter
    • Feces pass to the outside of the body through an opening called the anus.
      It has taken each of your meals about 24 hours to make this journey through your digestive system.
      Digestive system visual concept