Biology Digestion

act of eating

process of breaking down food ( enzymatic hydrolysis)

cells taking up smal molecules

Removal of undigestied material

Mouth, esophagus, stomach, small intestine, large intestine, rectum, anus

• Produces amylase and saliva to:
• - Activate taste buds
• - lubricates the digestive tract
• - creates a bolus (ball of food)

• Breaks down carbs
• - pH is 7-8

Involuntary transport of food from the mouth to stomach by rhythmic muscle contractions called peristalsis

• A part of the esophagus
• - a gate that controls the movement of food to the stomach and air to lungs

• - Stores food and starts protein digestion
• - breaks down food with physical( muscle contraction) and chemical digestion ( gastric gland)
• - pH of 2-3
• - Produces pepsin

• Produces:
• - Mucus: Protective coating to not digest your stomach lining
• - HCL: kills bacteria; activates pepsin from pepsinogen
• - Pepsin: enzyme that digests proteins

Protective mucus lining breaking down, exposing capillary network. Histamine.

• Physically digests food into smaller pieces.
• Diff teeth to process diff nutrients
• - incisors
• -canine
• - premolars

A long tube with a camera at the end

1. Ingestion- the act of eating

2. Digestions- Process of breaking down food (enzymatic hydrolysis)

3. Absorption- cells take up small molecules

4: Egestion- removal of undigested material

• Function: Chemically digests food, absorb nutrients, and transport undigested waste to the large intestine.
• Parts: Duodemun, jejunum, Ilium
• Covered in microvilli

A small vessel that absorbs fatty acids into the lymphatic systems.

• Secretes:
• - Bicarbonate ions to neutralize chyme from the stomach.
•    -Prosecretin -> secretin -> pepsin -> Pepsinogen
• - Trypsinogen -> trypsin ( Break polypeptides into peptide)
• - Erepsin to break down amino acids
• - Amylase to break down starch (carbs)
• - Lipase to break down lipids

Amylase: released in the mouth and pancreas

Bile salts: Made in the liver and released from the gall bladder. (not an enzyme)

Lipase: Released from the pancreas

• 1) Pepsin:  Deactivated by Bicarbonate after leaving the stomach
• 2) Trypsin: Activated in the small intestine 
• 3) Erepsin: released from the pancreas and small intestine for 2nd stage digestion

Produces bile salts, which are stored in the gall bladder, to emulsify fats in the duodenum.

Detoxifies the blood by filtering/ removing poisonous substances

Stores glycogen and Vitamin A, D, and B. 

Recycles old red blood cells

Absorbs water, salts, and some vitamins.

• Enormous microvillar surface.
• Synthesizes vitamins B and K

Food stimulates gastric juice production.

Gastrin (food in stomach) -> Parietal cells -> HCL (chemical digestion)

Esterogastrone: slows peristaltic movement

When muscles contract to move food from your esophagus to your stomach.

Breaks down the food and the digestive enzymes split up the proteins. The acidic gastric juice also kills bacteria. In the absence of HCL, pepsinogen is not activated and converted into pepsin, so protein digestion wouldn’t happen and it would not kill bacteria in the stomach.

1. teeth: physically digests food by breaking it into smaller pieces

2. larynx: protects the lower airways and facilitates respiration

3. liver: produces bile salts which are stored in the gallbladder to emulsify fats

4. gallbladder: stores and secretes concentrated bile from the liver

5. bile duct: allow bile to go from the liver and gallbladder into the small intestine

6. large intestine: helps the movement of food waste

7. appendix: unknown

8.salivary glands: initiates the breakdown of polysaccharides to simpler carbohydrates

9. tongue: facilitates the movement of food during mastication and assists with swallowing

10. esophagus: transport bolus of food from the mouth to stomach by rhythmic muscle contraction called peristalsis

11. stomach: storage of food and initial digestion of starch

12. duodenum: the first segment of the small intestine that is responsible for a large portion of the continuous breaking-down process

13. pancreas: produces digestive enzymes that act on food in the small intestine. stores bicarbonate ions that neutralize stomach acid

14. small intestine: completes the breakdown of proteins from disaccharides to monosaccharides

15. rectum/anus: hold stool and defecate

A1	Name	Produced	Works at
A	Lipase	pancreas, mouth, and stomach	small intestine
B	Bile salts	Liver	Duodenum
C	Pepsin	Stomach	Stomach
D	Trypsin	Pancreas	small intestine
E	Erepsin	Pancreas	stomach
F	Amylase	Mouth and pancreas	Mouth and small intestine