02 digestion

3,398 views

Published on

Published in: Health & Medicine
0 Comments
2 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
3,398
On SlideShare
0
From Embeds
0
Number of Embeds
29
Actions
Shares
0
Downloads
0
Comments
0
Likes
2
Embeds 0
No embeds

No notes for slide
  • http://www.youtube.com/watch?v=Z7xKYNz9AS0
    http://www.youtube.com/watch?v=Q-n_Q0qKXzg&p=D497D9E18CF729A7&playnext=1&index=2
    http://www.youtube.com/watch?v=j7fbiYVPDqY&feature=related
  • http://www.youtube.com/watch?v=e3O1AdlC8bI
  • http://www.youtube.com/watch?v=Z7xKYNz9AS0
    http://www.youtube.com/watch?v=Q-n_Q0qKXzg&p=D497D9E18CF729A7&playnext=1&index=2
    http://www.youtube.com/watch?v=j7fbiYVPDqY&feature=related
  • http://www.youtube.com/watch?v=Z7xKYNz9AS0
    http://www.youtube.com/watch?v=Q-n_Q0qKXzg&p=D497D9E18CF729A7&playnext=1&index=2
    http://www.youtube.com/watch?v=j7fbiYVPDqY&feature=related
  • http://www.youtube.com/watch?v=Z7xKYNz9AS0
    http://www.youtube.com/watch?v=Q-n_Q0qKXzg&p=D497D9E18CF729A7&playnext=1&index=2
    http://www.youtube.com/watch?v=j7fbiYVPDqY&feature=related
  • http://www.youtube.com/watch?v=Z7xKYNz9AS0
    http://www.youtube.com/watch?v=Q-n_Q0qKXzg&p=D497D9E18CF729A7&playnext=1&index=2
    http://www.youtube.com/watch?v=j7fbiYVPDqY&feature=related
  • http://www.youtube.com/watch?v=Q-n_Q0qKXzg&playnext=1&index=2&list=PLD497D9E18CF729A7
  • http://www.youtube.com/watch?v=b20VRR9C37Q
  • 02 digestion

    1. 1. Digestive Tract
    2. 2. Digestive Tract Digestion: The mechanical and chemical breaking down of food into smaller components
    3. 3. Digestive Tract Macromolecules: Large molecules that provide nutrition (i.e. energy) -Proteins -Nucleic acids -Carbohydrates -Fats
    4. 4. Digestive Tract: A Visual Journey Modern day technology allows us to see the journey that food takes through our bodies. Click on the video below:
    5. 5. Digestive Tract: Mouth, Teeth, Tongue, and Glands
    6. 6. Digestive Tract: Mouth, Teeth, Tongue, and Glands Tearing /Cuspid Grinding /Bicuspid Tearing and grinding Cutting
    7. 7. Digestive Tract: Mouth, Teeth, Tongue, and Glands
    8. 8. Digestive Tract: Mouth, Teeth, Tongue, and Glands
    9. 9. Digestive Tract: Mouth, Teeth, Tongue, and Glands
    10. 10. Digestive Tract: Mouth, Teeth, Tongue, and Glands Our tongues have several taste buds. Taste buds are receptors that send messages to the brain
    11. 11. Digestive Tract: Mouth, Teeth, Tongue, and Glands Saliva contains enzymes (i.e. amylase, which breaks down starch). In other organisms like insects, salivary glands are often used to produce proteins like silk or glues
    12. 12. Digestive Tract: Mouth, Teeth, Tongue, and Glands The salivary glands
    13. 13. Digestive Tract: Mouth, Teeth, Tongue, and Glands The saliva, teeth, mouth, and tongue form a food bolus This bolus goes on into the next part of the digestive tract
    14. 14. Digestive Tract: Pharynx and Epiglottis Pharynx
    15. 15. Digestive Tract: Pharynx and Epiglottis Epiglottis
    16. 16. Digestive Tract: Pharynx and Epiglottis The pharynx connects the oral cavity to the next part of the digestive system (the epiglottis and esophagus) The epiglottis prevents food from going into your lungs through the larynx
    17. 17. Digestive Tract: Pharynx and Epiglottis
    18. 18. Digestive Tract: Pharynx and Epiglottis Esophagus
    19. 19. Digestive Tract: Esophagus Esophagus: Muscular tube through which food passes from the pharynx to the stomach
    20. 20. Digestive Tract: Esophagus Peristalsis: Radially symmetrical contraction of muscles which forms a wave down the muscular tube.
    21. 21. Digestive Tract: Esophagus The esophagus is made up of circular and longitudinal layers of muscles (performs peristalsis). The inside is lubricated with mucous membranes Means “empty space”
    22. 22. Digestive Tract: Esophagus
    23. 23. Digestive Tract: Stomach Stomach
    24. 24. Digestive Tract: Stomach
    25. 25. Digestive Tract: Stomach Lower esophageal sphincter: If the lower esophageal sphincter is not closed properly, stomach acid enter the esophagus and cause heartburn Also known as cardiac sphincter
    26. 26. Digestive Tract: Stomach Stomach acid: -Also known as gastric juice -Contains hydrochloric acid (HCl) -pH of 2 (appoximately) -Contains digestive enzymes like pepsin (digests proteins) -Chemically breaks down food
    27. 27. Digestive Tract: Stomach Why doesn’t the acid burn through the stomach? The rugae lining the stomach continuously secretes mucus to protect the stomach The rugae allow the stomach to expand dramatically (up to 1 litre)
    28. 28. Digestive Tract: Stomach Sometimes the acid does burn through… The result is an ulcer Can be caused by -bacterial infection (i.e. Helicobacter Pylori) -weakened mucosal lining -anti-inflammatory medications (i.e. aspirin) -smoking is associated as well
    29. 29. Digestive Tract: Stomach Stomach Ulcer
    30. 30. Digestive Tract: Stomach Stomach has layers of muscles: -Oblique muscles -Longitudinal muscles -Circular muscles Helps mix gastric juice with food
    31. 31. Digestive Tract: Stomach
    32. 32. Digestive Tract: Stomach Multiple muscles contracting can make the surface of the stomach look something like this (this is not an image of the stomach): (Source: http://imgur.com/r/WTF/LdyACza)
    33. 33. Digestive Tract: Mouth to Stomach Our journey so far…
    34. 34. Digestive Tract: Stomach Pyloric sphincter
    35. 35. Digestive Tract: Stomach Pyloric Sphincter: Strong ring of smooth muscle which connects stomach to small intestines. Enables chyme (semi-digested food from stomach) to enter the duodenum.
    36. 36. Digestive Tract: Stomach Chyme
    37. 37. Digestive Tract: Stomach A short summary, and what happens next…
    38. 38. Digestive Tract: Small Intestines Small Intestine
    39. 39. Digestive Tract: Small Intestines Small Intestines: (3 parts) -Duodenum -Jejunum -Ileum
    40. 40. Digestive Tract: Duodenum, Pancreas, & Gall Bladder Duodenum: The gall bladder and pancreas have ducts going into the duodenum. -10-12 inches long -most chemical digestion takes place here
    41. 41. Digestive Tract: Duodenum, Pancreas, & Gall Bladder Pancreas: -Secretes sodium bicarbonate (baking soda) to neutralize stomach acid -Secretes pancreatic juice, a mixture of enzymes like trypsin, pancreatic lipase, pancreatic amylase
    42. 42. Digestive Tract: Duodenum, Pancreas, & Gall Bladder Pancreas: Also produces insulin from the Islets of Langerhans
    43. 43. Digestive Tract: Duodenum, Pancreas, & Gall Bladder Gall Bladder: Stores bile produced by the liver. Bile emulsifies fats to allow greater surface area for fat enzymes (lipases) to work
    44. 44. Digestive Tract: Duodenum, Pancreas, & Gall Bladder Bile is made from cholesterol and bile salts The resulting molecule is like dish detergent
    45. 45. Digestive Tract: Duodenum, Pancreas, & Gall Bladder Gallstones: Crystallization of bile components (primarily cholesterol). Causes: -diet -body weight -bile duct motility -gall bladder motility
    46. 46. Digestive Tract: Duodenum, Pancreas, & Gall Bladder Gallstones
    47. 47. Digestive Tract: Duodenum, Pancreas, & Gall Bladder Gallstones
    48. 48. Digestive Tract: Duodenum, Pancreas, & Gall Bladder Gallstones
    49. 49. Digestive Tract: Jejunum Jejunum: Roughly 2.5 meters long. Absorption takes place here Jejunum
    50. 50. Digestive Tract: Jejunum Jejunum: Lined with longitudinal and circular muscles to perform peristalsis. Has structures called villi.
    51. 51. Digestive Tract: Jejunum Villi: -finger-like projections of the small intestine lining - More surface area to absorb nutrients. The cells lining each villus can perform -Active transport (transport of nutrients requiring energy) -Passive transport (transport of nutrients not requiring energy)
    52. 52. Digestive Tract: Jejunum Villi
    53. 53. Digestive Tract: Ileum Ileum: -2.4 meters long -absorption (has villi) -also absorbs vitamin B12 and bile salts
    54. 54. Digestive Tract: Ileum
    55. 55. Digestive Tract: Caecum & Appendix Caecum
    56. 56. Digestive Tract: Caecum & Appendix Caecum: -first part of the large intestine -Attached to the appendix
    57. 57. Digestive Tract: Caecum & Appendix Caecum: -separated from the ileum by the ileocaecal valve.
    58. 58. Digestive Tract: Caecum & Appendix Appendix: -blind-ended tube -believed to shelter beneficial bacteria for digestion -can become infected (appendicitis)
    59. 59. Digestive Tract: Caecum & Appendix Appendix
    60. 60. Digestive Tract: Large Intestines Colon: -Absorbs water -Pass waste material from the body -Contains colonic bacteria which produce vitamin K, vitamin B12, thiamine, and riboflavin (mutualistic relationship)
    61. 61. Digestive Tract: Large Intestines Colon Cancer: -4th most common type of cancer (3rd most common death-causing cancer) -Starts with benign tumours (polyps), which become malignant Causes range from genetics and/or viral infections (i.e. HPV) to lifestyle causes (diet low in vegetables and fruit, and smoking*) *smoking is correlated
    62. 62. Digestive Tract: Large Intestines Colon Cancer
    63. 63. Digestive Tract: Large Intestines Diverticula: -Small pouches in the lining of colon, causing the condition diverticulosis -Pouches get inflammed and swell (diverticulitis)
    64. 64. Digestive Tract: Large Intestines Diverticulosis: -Caused by low fibre diet -Lack of exercise associated -Muscles in colon wall weaken if feces are hard to push downward, and eventually bulge outward
    65. 65. Digestive Tract: Large Intestines Diverticulosis
    66. 66. Digestive Tract: Large Intestines Diagnostic: Barium Enema • Barium solution is inserted into rectum, to provide contrast for the X-ray • An X-ray is taken to see how barium fluid moves through the large intestine (checks for blockages, leaks, abnormal structures)
    67. 67. Digestive Tract: Rectum, Anal Canal, Anus Rectum: -Forms peristaltic waves to expel feces through the anal canal -Stretch receptors trigger contractions when rectum is full
    68. 68. Digestive Tract: Rectum, Anal Canal, Anus Anal sphincter: Exterior and interior sphincters pull the anus up over the exiting feces
    69. 69. Digestive Tract: The Whole Journey Click the video below for a summary of the whole digestive system

    ×