Dig Flashcards
Majority of digestion takes place in ___ organ + length of the organ + its three parts
- The small intestine
- 6-7 meters
- A) Jejunum
B) ileum
C) duodenum
How long is the duodenum?
10-12 inches
What controls the flow of material into the duodenum?
Pyloric sphincter
What two organs produce secretions that end up in the duodenum?
- The pancreas
- The liver
What does the liver produce?
Bile
What gives bile it’s greenish colour
Bilirubin
Where is bile stored?
In the gall bladder
What does an emulsifying agent do?
Breaks down large fats to increase surface area
What do bile salts do?
Emulsify + digest fats
What sodium compound does pancreatic juices contain?
Sodium bicarbonate
What does sodium bicarbonate do?
Neutralizes the chymes acidity
What three enzymes does the pancreatic juices contain + their function?
- Amylase: breaks down carbohydrates (starch)
- Lipase: breaks down carbohydrates (lipids)
- Trypepsin: breaks down proteins
What produces the intestinal juices in the small intestine
Intestinal glands
2 Intestinal juice enzymes and their functions:
- Maltose: breaks down maltose into glucose
- Peptidase: breaks down peptides into amino acids
Where does absorption take place?
Small intestine (villi + microvilli)
Is absorption passive? what does it require?
Mostly passive, requires ATP
Where do sugars and amino acids go?
Bloodstream —> villi
Where do glycerol and fatty acids go?
Absorbed via lacteals in villi
What is the function of the hepatic portal vein?
Carries blood to the small intestine to the liver before circulation
What is movement of the gut to push food through the gut tube called?
Peristalsis: keeps bolts moving in one direction throughout the digestive tract
The 7 functions of the liver:
- Detoxifies blood
- Stores glucose as glycogen, (then can convert glycogen to glucose when blood sugar levels drop)
- Destroys old red blood cells + converts hemoglobin to bile and stored bile in the gall bladder for fat emulsification
- Produces urea from breakdown product of amino acids (urea is a nitrogenous waste that the liver removed from urine)
- Makes blood proteins (albumins + fibrinogen from breakdown of amino acids)
- Converts amino acids to glucose “gluconeogenesis”
- Regulate blood cholesterol levels by converting bike salts for digestion + absorption
- Liver stores iron+ vitamin A, D, E, K, B12
What is bilirubin?
The breakdown product of hemoglobin, high amounts of bilirubin can cause jaundice
3 main functions of stomachs in humans
- Temporarily store food.
- Contract and relax to mix and break down food.
- Produce enzymes and other specialized cells to digest food.
Explain the significance of pH with respect to the secretions of the stomach and intestine
Stomach: low pH activates pepsin which digests large proteins to small amino acid chains
Intestine: high pH neutralizes stomach pH
