Digestive System

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Digestive System
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Functions of the Digestive System

• Ingestion food
• enters the mouth

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Functions of the Digestive System

• Ingestion food enters the
• mouth
• Digestion
• process that breaks
• food down into
• small molecules

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Functions of the Digestive System

• Ingestion food enters the
• mouth
• Digestion process that
• breaks food down into small
• molecules
• Mechanical
• digestion food is
• chewed and churned
• Chemical digestion
• breaks down large food
• molecules into smaller
• molecules to be
• absorbed by cells

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Functions of the Digestive System

• Ingestion food enters the
• mouth
• Digestion process that
• breaks food down into small
• molecules
• Absorption
• small molecules of
• food are taken into
• the body cells

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Functions of the Digestive System

• Ingestion food enters the
• mouth
• Digestion process that
• breaks food down into small
• molecules
• Absorption small
• molecules of food are taken
• into the body cells
• Elimination
• wastes made of
• unabsorbed food
• molecules pass out of the body

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Which is not a function of the digestive system?

1. Breaking down food into molecules the body can
   use
2. Absorbing food molecules into the blood to
   deliver to the body
3. Changing waste into molecules the body can use
4. Eliminating undigested waste from the body

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Organs of the Digestive Tract

1. Mouth digestion starts here

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Organs of the Digestive Tract

• Mouth digestion starts here
• Tongue teeth mechanically break food up

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Organs of the Digestive Tract

• Mouth digestion starts here
• Tongue teeth mechanically break food up
• Saliva chemically digests food
• Saliva mostly made of
• water, also contains
• mucus ptyalin (an
• enzyme)

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Organs of the Digestive Tract

• Mouth digestion starts here
• Tongue teeth mechanically break food up
• Saliva chemically digests food
• Saliva mostly made of
• water, also contains
• mucus ptyalin (an
• enzyme)
• When swallowing, epiglottis
• (a small flap of tissue) automatically closes
  over the trachea (windpipe)

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Organs of the Digestive Tract

• Esophagus
• Smooth muscles force food into the mucus-lined
  esophagus
• Rhythmic muscular
• contractions
• (peristalsis) push food
• downward

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Organs of the Digestive Tract

• Stomach
• Food undergoes mechanical digestion when stomach
  muscles churn the food
• Chemical digestion
• happens when hydrochloric
• acid (HCl) and pepsin
• break down the complex
• proteins
• Peristalsis pushes the food
• toward stomachs exit

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Which is not an example of mechanical digestion?

1. Teeth chewing food
2. Tongue breaking up food
3. Smooth muscles in stomach churning food
4. Pepsin HCl breaking down proteins

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What are the muscle contractions that push food
through the digestive system called?

1. Elimination
2. Peristalsis
3. Epiglottis
4. Pepsin

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What is this structure?

1. Mouth
2. Epiglottis
3. Esophagus
4. Stomach

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Participant Scores
400
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Organs of the Digestive Tract

• Small Intestine (6 meters long)
• Most digestion happens here
• Intestinal juice
• (full of enzymes)
• breaks down food

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Organs of the Digestive Tract

• Small Intestine (6 meters long)
• Most digestion happens here
• Intestinal juice (full of enzymes) breaks down
  food
• Digestive Helpers
• Liver bile is
• produced here (Bile
• breaks up fats like
• dish detergent
• breaks up grease)

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Organs of the Digestive Tract

• Small Intestine (6 meters long)
• Most digestion happens here
• Intestinal juice (full of enzymes) breaks down
  food
• Digestive Helpers
• Liver bile is produced
• here (Bile breaks up fats
• like dish detergent breaks
• up grease)
• Gall bladder bile
• is stored here until
• released into the small intestine

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Organs of the Digestive Tract

• Small Intestine (6 meters long)
• Most digestion happens here
• Intestinal juice (full of enzymes) breaks down
  food
• Digestive Helpers
• Liver bile is produced
• here (Bile breaks up fats
• like dish detergent breaks
• up grease)
• Gall bladder bile is
• stored here until released
• into the small intestine
• Pancreas produces
• pancreatic juices that
• are released into the small intestine to break
  down proteins,starches, fats

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Organs of the Digestive Tract

• Small Intestine (6 meters long)
• Most digestion happens here
• Intestinal juice (full of
• enzymes) breaks down food
• Digestive Helpers
• Liver
• Gall bladder
• Pancreas
• Digested food is
• absorbed through the villi into a network of
  blood vessels that carry the nutrients to all
  parts of the body

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Organs of the Digestive Tract

• Small Intestine (6 meters long)
• Most digestion happens here
• Intestinal juice (full of enzymes)
• breaks down food
• Digestive Helpers
• Liver, Gall bladder, Pancreas
• Digested food is absorbed
• through the villi into a network of
• blood vessels that carry the
• nutrients to all parts of the body
• e) By the time food leaves the small intestine,
  it is empty of all nutrients except water

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Where does most digestion take place?

1. Mouth
2. Stomach
3. Small intestine
4. Liver

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Which is true about bile?

1. Bile breaks down proteins.
2. Bile is produced in the liver.
3. Bile is stored in the pancreas.
4. Bile is released into the stomach.

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What is this structure?

1. Liver
2. Stomach
3. Gall bladder
4. Pancreas

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Participant Scores










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Organs of the Digestive Tract

• Large Intestine (1.5 meters long)
• Undigested food spends 18-24 hours here most of
  the water is absorbed

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Organs of the Digestive Tract

• Large Intestine (1.5 meters long)
• Undigested food spends 18-24 hours here most of
  the water is absorbed
• Helpful bacteria
• living in large
• intestine make
• vitamins K B

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Organs of the Digestive Tract

• Large Intestine (1.5 meters long)
• Undigested food spends 18-24 hours here most of
  the water is absorbed
• Helpful bacteria living in
• large intestine make vitamins
• K B
• Materials not
• absorbed form into
• solid waste (dead
• bacteria, some fat
• protein, undigested
• food, dried out parts of
• digestive juices old intestinal cells)

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Organs of the Digestive Tract

• Large Intestine (1.5 meters long)
• Undigested food spends 18-24 hours here most of
  the water is absorbed
• Helpful bacteria living in large
• intestine make vitamins K B
• Materials not absorbed form into
• solid waste (dead bacteria,
• some fat protein, undigested
• food, dried out parts of digestive
• juices old intestinal cells)
• Solid waste passes
• into the rectum and is stored until it is
  eliminated from the body through the anus

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Which process occurs in the large intestine?

1. Digested food is absorbed.
2. Undigested food is absorbed.
3. Water is added to undigested food.
4. Water is absorbed from undigested food.

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Which structure is the large intestine?

1. A
2. B
3. C
4. D

A
B
C
D
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What do the bacteria in the large intestine do?

1. Make you sick
2. Make bile
3. Make vitamins
4. Make food

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Final Participant Scores
300
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300