2. 13 The Digestive System and Nutrition
Lesson 13.1: Nutrition Lesson 13.2: Anatomy and Physiology of the Digestive System Lesson 13.3: Disorders and Diseases of the Digestive System

3. Chapter 13: The Digestive System and Nutrition
Lesson 13.1
Nutrition

4. Do Now Grab your folders.
Begin working on your “Learning the Key Terms” worksheet.
Chapter 12 Lesson 3 vocab is on page 437.
You have 8 minutes to complete the worksheet.
Turn in the worksheet to Mr. B when you are finished.

5. Today’s Objectives Identify the major categories of nutrients.
Identify nutrients that can have negative effects on your health, and describe the negative effects.

6. Nutrition
Intro
Why are we starting the digestive system with nutrition?
The digestive system exists to provide nutrients to the body.
We will study the nutrients found in the food we eat before we examine the digestive system itself.

7. Nutrition
Energy
As you are sitting in class, your body is growing, breathing, moving, pumping blood, and staying warm.
In order to perform all of those activities your body needs energy.
Energy is the ability to do work.
There are many different forms of energy:
Heat, chemical energy, kinetic energy, potential energy.

8. Energy measuring the body’s energy use basal metabolic rate
Food energy is measured in terms of an item’s capacity to produce heat.
Heat energy is measured in calories
Calories are also called kilocalories
basal metabolic rate
energy required for one day at rest
varies by individual
Factors include: age, gender, height, body mass, and body fat percentage.
The more active you are, the more calories you need.

9. Macronutrients, Vitamins, and Minerals
substances needed for
energy
growth
maintenance
Tischenko Irina/Shutterstock.com

10. Nutrients Macronutrients Essential Nutrients carbohydrates proteins
fats (lipids)
Essential Nutrients
vitamins
Minerals
Dietary Guidelines for Americans creates guidelines or standards for achieving a healthy diet.

11. Carbohydrates
Sugars and starches are foods or ingredients in foods that are classified as carbohydrates.
1 gram supplies 4 Calories
one half of daily caloric intake should be from carbohydrates
No more than 25% of carbohydrate calories should come from sugars found in soft drinks or sweet foods.

12. Proteins Proteins are made of amino acids essential amino acids
must be part of diet
nonessential amino acids
body can make
one gram supplies 4 Calories
one quarter of daily caloric intake from proteins
Good sources of protein include meat, beans, peas, rice, corn or wheat.
Joshua Resnick/Shutterstock.com

13. Fats Also known as lipids Contain different types of fats:
saturated fats
monounsaturated fats
Canola and olive oil
polyunsaturated fats
Corn and soybean oil
trans-unsaturated fats (trans fats)

14. Fats
one gram supplies 9 Calories of energy, about twice as much energy per gram compared to carbohydrates or proteins.
minimize trans and saturated fat intake – too much can lead to cardiovascular system diseases
less than 25–35% of total calories from fat

15. Vitamins chemicals needed for metabolism to function properly.
The body only needs small amounts of vitamins to achieve good health.
Most vitamins must be obtained from food.
types of vitamins
fat-soluble
may be stored in the body
water-soluble
are not stored in the body
Excess water soluble vitamins are expelled through the urine.
vitamin deficiency can cause health problems.
Ex: Osteoporosis.

16. Minerals elements needed for proper body function examples
Calcium – major component of bone
potassium
Iron – helps red blood cells transport oxygen
phosphorus

17. Water-Soluble Vitamins

18. Fat-Soluble Vitamins

19. Minerals

20. Review and Assessment
Match these words with 1–4 below: carbohydrate, fat, vitamin, iron.
1. 9 calories per gram
2. water soluble
3. sugar
4. mineral

21. END

22. Exit Ticket
Food scientists use the kilocalories, or _____, to measure the potential energy in food.
a. kinetic energy
b. heat
c. calorie
d. metabolism

23. 2) Which of the following is not a nutrient. a. proteins b. vitamins c
2) Which of the following is not a nutrient? a. proteins b. vitamins c. bacteria d. water

24. 3) Proteins are made up of varying amounts of 20 different ___________
3) Proteins are made up of varying amounts of 20 different ___________. a. vitamins b. lipids c. chromosomes d. amino acids

25. 4) Which of the following types of fats are considered to be dangerous to your health? a. Saturated fat b. Unsaturated fat

26. 5) T or F: The basal metabolic rate is used to identify the amount of energy required to sustain a person’s metabolism for one day while working out.

27. Anatomy and Physiology of the Digestive System
Chapter 13: The Digestive System and Nutrition
Lesson 13.2
Anatomy and Physiology of the Digestive System

28. Do Now Grab your folders.
Begin working on your “Learning the Key Terms” worksheet.
Chapter 13 Lesson 2 vocab is on page 478.
You have 8 minutes to complete the worksheet.
Turn in the worksheet to Mr. B when you are finished.

29. Today’s Objectives
Identify the organs of the digestive system and explain their functions.
Describe how food is digested and absorbed.

30. Digestive System
Intro
The digestive system consists of a tube running through the body with organs alongside of it.
Food goes in one end, is broken down, and is partly absorbed.
The substances not absorbed into the body, exit on the other end.
The tube is called the alimentary canal, or the gastrointestinal tract***.
Begins in the mouth and ends with the anus.
Primary organs of the digestive system:
Pharynx, esophagus, stomach, small intestine, and large intestine.
Accessory organs include: salivary glands, pancreas, liver, and gallbladder.

31. Anatomy and Physiology of the Digestive System
What we’re covering:
activities of digestion
layers of the alimentary canal
digestive organs and their functions

32. Activities of Digestion
6 Activities Involved with Digestion
(1) ingestion
getting food into the body
Involves the mouth, teeth, tongue
(2) propulsion
Begins after ingestion
moving food along GI tract
Propulsion is initiated by swallowing at the pharynx and peristalsis – contraction of muscles that move the food down the GI Tract***.

33. Activities of Digestion
(3) mechanical breakdown***
breaks food into smaller pieces
increases surface area of food
Chewing food, the churning in the stomach, and muscle contractions in the small intestine all contribute to the mechanical breakdown of food.
(4) chemical breakdown***
also known as digestion
Enzymes along the GI Tract break down large particles of food.

34. Activities of Digestion
(5) absorption
digested food particles moved into blood
Once absorption has occurred, the blood carries the food to other parts of the body.
(6) defecation
expulsion of food that was not absorbed.
The waste matter exits the body via the anus.

35. Activities of Digestion

36. Layers of the Alimentary Canal
The walls of the alimentary canal have four basic layers.
From the inside out the layers are:
Mucosa
Submucosa
Muscularis externa
Serosa
Mucosa (Mucous Membrane)
innermost layer
adjacent to lumen
Surface is covered by mucus

37. submucosa below mucosa
Layer of irregular, dense connective tissue containing blood vessels, lymphatic vessels, and nerves.
Secrete substances that aid in digestion and absorption.

38. Layers of the Alimentary Canal
muscularis externa
Surrounds the submucosal layer
Has two layers of smooth muscle
Propels the food through the alimentary canal (GI Tract)
Performs the mechanical breakdown of food
circular muscle
longitudinal muscle

39. serosa outermost layer of the GI Tract Considered a serous membrane
Serous membranes are thin, slippery membranes that minimize friction between organs and the cavity wall.
Abdominopelvic cavity contains most of the organs of digestion.
Also known as the peritoneum – divided into 2 layers
visceral
parietal

40. Layers of the Alimentary Canal

41. Review and Assessment True or False?
1. Mechanical breakdown decreases the surface area of food.
2. The mucosa is adjacent to the lumen.
3. Peritoneum is serosa.
4. In absorption, digested food moves into the blood.

42. Digestive Organs and Their Functions

43. Digestive Organs and Their Functions
The digestive process involves several organs throughout the body.
Some organs play a major role, while others aid in the process of digesting and absorbing nutrients.

44. The Oral Cavity Also known as the mouth***.
Mouth helps accomplish four of the six key activities:
Ingestion of food
Mechanical breakdown of food (chewing)
Chemical breakdown of food (saliva)
Propulsion of food
Lips – grab food and pull into the mouth
Tongue – contains taste buds, moves and manipulates food.
Cheeks – lateral borders of the mouth
palate
hard
soft

45. The Nasal Cavity passageway for air entering and leaving the nose.
uvula
hangs from soft palate
keeps food out of nasal cavity when swallowing

46. Teeth and Gums gum Teeth Gingiva
Covers the neck of the teeth, maxilla (upper jaw), and mandible (lower jaw)
Teeth
We use our teeth to begin mechanical breakdown of food.
Deciduous (temporary teeth)
Children have 20 temporary teeth
Permanent – 32 teeth
Incisor – front 4 teeth on top and bottom, good for cutting.
Canine – lateral and posterior to the incisors
Molar – 2 molars follow each canine, good for crushing & grinding.

47. Anatomy of the Tooth

48. Anatomy of the Tooth
The part of the tooth that project out of the jawbone is the crown – white portion
The portion of the tooth embedded in the jawbone is the root.
The part between the crown and the root is the neck.
Each tooth is coated in enamel. Enamel is the hardest material in the body.
The body of the tooth is made of dentin.
The hollow region inside of the tooth is called the pulp cavity.
The root canal provides a passageway for the nerves and blood vessels to reach the pulp cavity.

49. Salivary Glands
First accessory organs of digestion that contribute to the chemical breakdown of food – three pairs of salivary glands.
Salivary glands secrete saliva into the mouth.
Parotid glands – largest salivary glands just under the skin below and in front of the ears.
Submandibular – lower part of mandible
Sublingual – under sides of the tongue
saliva
Composed of water
enzymes

50. Pharynx
The region that connects the mouth and the nasal cavity to the trachea and the esophagus.
laryngopharynx
Glottis – opening to the larynx and trachea.
epiglottis

51. Esophagus connects pharynx to stomach peristalsis
muscle contraction changes size of tube
food is moved through GI tract – specifically into the stomach.

52. Stomach
The stomach is a reservoir in which food is broken down both mechanically and chemically before it enters the small intestine.
There are four major regions: cardia, the fundus, the body, and the pyloric region.
The empty stomach has an internal volume of about 50 ml.
Stomach stretches to hold up to 2 liters or more.

53. Stomach regions three layers of muscle Cardia Fundus Body
Closest to the opening of the esophagus
Fundus
Upper end of the stomach
Body
Middle portion of the stomach
pyloric region
Lower end
three layers of muscle

54. Lining of the Stomach Stomach has gastric pits – tiny openings
Each of these openings leads to a gastric gland.
gastric gland
mucus-secreting cells that secrete gastric juice
Stomach is very acidic – helps to kill bacteria and digest food.
How does the body protect itself from such strong acid?
Enough mucus must be produced to protect the lining of the stomach.

55. END

56. EXIT TICKET The alimentary canal is also known as _______. a. stomach
b. small intestine
c. gastrointestinal tract
d. oral cavity

57. 2) The ______ breakdown of food reduces food into smaller pieces through chewing and stomach churning. a. mechanical b. chemical

58. 3) The process of muscles contracting for the purpose of moving food particles along the GI tract is called a. absorption b. peristalsis c. ingestion d. churning

59. 4) The mouth is also called ______. a. mucosa b. alimentary canal c
4) The mouth is also called ______. a. mucosa b. alimentary canal c. oral cavity d. submucosa

60. 5) There are ____ pairs of salivary glands in the mouth. a. three b
5) There are ____ pairs of salivary glands in the mouth. a. three b. five c. seven d. nine

61. Chapter 13.2 Anatomy and Physiology of the Digestive System Part 2

62. Do Now

63. Today’s Objectives
Identify the organs of the digestive system and explain their functions.
Describe how food is digested and absorbed.

64. Chemical Reactions in the Stomach
Secretions in the GI tract creates a potentially dangerous situation:
The enzymes could start digesting or breaking down the body’s own tissues
As long as there is enough mucus produced, it will prevent the walls of the stomach from eroding.
chyme formation
When food enters the stomach, it mixes with acidic gastric juice to form chyme.
stomach contractions
Keep the mixture well mixed.

65. Review and Assessment
Match these words with 1–4 below: canine, fundus, parotid, esophagus.
1. region of stomach
2. connects pharynx to stomach
3. a type of tooth
4. a type of salivary gland

66. Small Intestine
The small intestine gets its name from its diameter, which is much smaller than that of the large intestine.
Longest segment of the GI Tract
It is the site of all food absorption and most water absorption.
Small intestine has 3 segments***
duodenum
jejunum
ileum
Lining
Inner surface of the small intestine has circular folds.
The surface of each fold is covered with finger like projections called villi.

67. Small Intestine chemical breakdown absorption into the blood
emulsification by bile – breaks down large fat particles into smaller particles.
break down by enzymes
absorption into the blood
Absoprtion of food molecules into the blood occurs in all three segments of the small intestine.
from capillaries to the blood

68. The Liver functions of the liver***
Most of the functions of the liver are related to the synthesis and processing of various chemicals.
maintains nutrients in blood
converts one nutrient to another
stores nutrients
inactivates toxins

69. The Liver The Liver’s blood supply
hepatic portal vein – the liver receives blood from the stomach and intestines from the hepatic portal vein.
parts of the liver
Lobules – the liver is made up of millions of lobules.
Hepatocytes (liver cells)
blood vessels
bile canaliculi – ducts that collect bile
bile salts – help to break apart fats.

70. Liver and Gallbladder

71. The Gallbladder functions of the gallbladder
stores bile produced by liver and delivers it to the duodenum.
releases bile when fat-containing chyme is in duodenum
You can live without a gallbladder.

72. Pancreas An accessory organ of digestion.
Located behind and underneath the stomach.
Secretes pancreatic juices into the duodenum
contain digestive enzymes that help break down starches.
glucose regulation
Metabolic function of the pancreas is to secrete hormones that regulate the concentration of glucose in the blood.
beta cells – produce insulin and secrete it into the blood
alpha cells – produce glucagon and secrete it in the pancreas when glucose levels are low.

73. Large Intestine
Has a larger diameter than the small intestine, but a shorter length.
4 regions: Cecum, Colon, Rectum, and Anal Canal.***
Cecum – the first part of the large intestine to receive food from the small intestine.
Partially controlled by the nervous system.
Appendix hangs off of the lowest part of the cecum.
Colon – Has 4 major segments:
Ascending – extends upward from the cecum to the right kidney
Transverse – crosses from right to left
Descending – comes after the transverse colon
sigmoid – twists around and ends at the rectum

74. Rectum, Anal Canal, and Anus
Short segment whose lower end comprises the anal canal.
anal canal
anus
The opening to the outside world, is usually closed due to constriction of the internal and external anal sphincters.
sphincters
internal
external

75. Review and Assessment
Match these words with 1–4 below: jejunum, sigmoid, beta cells, gallbladder. 1. a region of the colon 2. a region of the small intestine 3. stores bile 4. produce insulin

76. END

77. Exit Ticket
The three segments of the small intestine, beginning with the segment closest to the stomach, are the _________.
a. ileum, jejunum, and cecum
b. duodenum, jejunum, and ileum
c. cecum, colon, and ileum
d. jejunum, ileum, and duodenum

78. 2) The four major segments of the large intestine, starting with the segment closest to the small intestine, are the ____. a. cecum, rectum, colon, and anal canal b. cecum, anal canal, rectum, and colon c. anal canal, rectum, colon, and cecum d. cecum, colon, rectum, and anal canal

79. 3) Which of the following is NOT a function of the liver. a
3) Which of the following is NOT a function of the liver? a. maintains nutrients in the blood. b. converts one nutrient to another c. collects glucose d. stores nutrients

80. 4) T or F: The pancreas is responsible for both digestive (secrete pancreatic juices) and metabolic functions (make insulin and glucagon).

81. Disorders and Diseases of the Digestive System
Chapter 13: The Digestive System and Nutrition
Lesson 13.3
Disorders and Diseases of the Digestive System

82. Do Now Grab your folders and a Do Now Sheet.
Chapter 13 Lesson 3 vocab is on page 483.

83. Today’s Objectives
Describe some of the common disorders and diseases of the digestive system.
Explain the damage that gingivitis can do in the oral cavity as well as throughout the entire body.
Describe lifestyle changes that would lessen the symptoms of gastroesophageal reflux disease.

84. Common Digestive Disorders
Intro
Digestive ailments are some of the most common reasons that people need medical attention.
Anything we eat, we put into our bodies. Each of these substances potentially contain pathogens.

85. Disorders and Diseases of the Digestive System
Remember: the digestive system does not just contain the stomach. The oral cavity, which is a part of the GI Tract, affects the entire body.
Periodontal disease – disease that affects the supporting structure of the teeth.
Gingivitis
Inflammation of the gingiva or gum tissue
Most common periodontal disease
Caused by long-term plaque accumulation on the teeth.
Plaque is a sticky mixture of bacteria, food particles, and mucus that hardens to form tartar.
Untreated gingivitis can lead to tooth loss.

86. Disorders and Diseases of the Digestive System
People with gingivitis are at an increased risk of developing cardiovascular disease.
How would gum disease relate to heart disease?
It is believed the inflammation of the gum tissues causes the body to move into a pro-inflammatory state, leading to the likelihood or atherosclerosis, or the hardening of your arteries.
Gingivitis causes bacteria to get into your bloodstream. Once in the bloodstream, it can go anywhere in the body. Inflammation can cause damage to the blood vessels, including those in the heart.

87. Disorders and Diseases of the Digestive System
Gastroesophageal reflux disease (GERD)
Movement of chyme from the stomach into the lower esophagus.
Remember: the stomach wall is protected from the acid by a thick layer of mucus.
The esophagus, however, is not protected from this acid.
Gastroesophageal reflux is commonly known as heartburn.
Chronic heartburn can lead to GERD
Treatment: eating smaller more frequent meals

88. Disorders and Diseases of the Digestive System
Ulcers
Peptic Ulcers – break in the protective lining of the stomach, duodenum, or lower esophagus.
Can be extremely painful because of the exposed lining to the acidic conditions.
Most ulcers are caused by infection from the bacterium Helicobacter pylori.
Myth: hot and or spicy food does not cause ulcers. They may make a condition worse, but won’t necessarily cause ulcers.

89. Disorders and Diseases of the Digestive System
Gastroenteritis
inflammation of stomach or intestine
Symptoms include nausea, vomiting, diarrhea, and abdominal pain.
Can often be contagious and sometimes referred to as the stomach flu.
Inflammatory bowel disease
Walls of the small or large intestine become chronically inflamed.
Results in diarrhea and stomach pain.
ulcerative colitis
Affects only the colon and the mucosal layer of the intestines.
Crohn’s disease
Can affect all four layers of the digestive tract wall.
Suffer from malabsorption which can result in weight loss.

90. Constipation
Are often symptoms of other diseases.
Constipation is the difficulty or inability to defecate regularly, causing waste to spend too much time in the colon.
So much water is absorbed from the waste that it becomes nearly solid, making it more difficult to pass.
Causes of constipation:
Weakness in bowel muscles
Lack of fiber
Lack of exercise
Prescription drugs

91. Diarrhea
Characterized by abnormally frequent, water bowel movements.
Occurs when waste does not spend enough time in the colon where excess water would be absorbed.
Causes of diarrhea:
Dysentery (infection of the intestines or stomach from bacteria, virus, or parasites.
Food poisoning
Inflammatory bowel disease
Consuming milk when lactose intolerant.

92. Disorders and Diseases of the Digestive System
hepatitis
inflammation of liver
Caused by viral infections, excessive use of alcohol.
Common symptoms include jaundice, yellowing of the skin or eyes.
pancreatitis
inflammation of pancreas
Occurs when pancreatic enzymes stay active in the pancreas. The causes the pancreas to break down its own tissues.

93. ` gallstones bile forms crystals
Can get stuck in the ducts of the gallbladder
Causes pain and the inability to digest fat
Cholecystectomy – removal of the gallbladder.
People with no gallbladder must eat smaller, more, frequent, and less fatty meals.
cancer
digestive system cancers are common
Colon cancer is the third most common cancer in men and women, and the 2nd leading cause of cancer-related deaths.
Typically grow slowly.
Intestines can be screened for precancerous growths.
Colonoscopy is a common screening for cancers of the colon and rectum.

94. Review and Assessment
Fill in the blanks with: tartar, gallstones, hepatitis, or ulcers. 1. Helicobacter pylori causes _______________. 2. Inflammation of the liver is _______________. 3. Plaque forms _______________. 4. Crystals of bile are _______________.

95. END

96. EXIT TICKET Gingivitis is an inflammation of the _____, or gum tissue.
a. periodontal
b. plaque
c. molar
d. gingiva

97. 2) Because of the location, gastroesophageal reflux disease (GERD) is also known as what? a. gastroenteritis b. ulcer c. heartburn d. hepatitis

98. 3) ____ can be caused by waste spending too much time in the colon. a
3) ____ can be caused by waste spending too much time in the colon. a. diarrhea b. constipation c. Chron’s disease d. plaque

99. 4) _____ are solid crystals that form from bile and can block the secretion of bile into the small intestine. a. kidney stones b. plaque c. tartar d. gallstones