Digestive system 🍏 Flashcards
(35 cards)
What are the components of the digestive system?
- buccal/oral cavity
- salivary glands
- oesophagus
- stomach
- liver
- pancreas
- gallbladder
- small intestine
- large intestine
- rectumn
- anus
What are the 3 types of salivary glands
submandibular, sublingual, parotid
What does the enzyme saliva consist of, and what is the function of the enzyme?
Saliva consists of an enzyme called amylase, and amylase begins the digest the food and convert starch into maltose
What is peristalisis?
Peristalsis is the involuntary muscle movement of the oesophagus which propels food from the buccal cavity to the stomach in a wave like motion.
How do the toxic stomach acids and pepsin not affect the stomach lining?
Because the stomach has a mucous layer which protects the stomach lining
How does the stomach wall produce the gastic acid?
There are gastric glands on the stomach wall’s inner lining and they produce gastric acid by simply seeing or smelling the food.
How is the stomach and oesophagus separated if it does not have a protective mucus layer?
The stomach and oesophagus are separated by a sphincter. The sphincter opens when the bolus is pushed and contracts when it enters.
What does gastric acid consist of?
- hydrochloric acid
- pepsin
- lipase
- intrinsic factor
What is the function of hydrochloric acid, and what does it convert?
Hydrochloric acid destroys the bacteria present in food and converts pepsinogen into pepsin.
What is the intrinsic factor?
It is a substance produced by the stomach and it absorbs vitamin B12 which is crucial for the production of red blood cells.
What does the bolus convert to in the stomach?
The bolus converts into chyme
What are the 2 types of sphincters in the stomach
Pyloric sphincter
Upper Esophageal Sphincter
Why does the pyloric sphincter only open a few millimetres?
The pyloric sphincter only opens a few millimeters so that larger pieces remain in the stomach to turn into chyme
What are the 3 sections of the small intestine
Duodenum
Jejunum
Ileum
What happens in the first section of the small intestine?
In the first section of the small intestine, the duodenum, bile and pancreatic juice are mixed with the chyme
Why must the proenzymes and enzymes have a higher pH value than in the stomach?
The enzymes and proenzymes in the pancreatic juice must have a higher pH value than that in the stomach for them to do their job, because the low pH can denature or inactivate them
What is enterokinase, and how does it affect the digestive system?
Enterokinase is an enzyme in the small intestine that activates trypsin from trypsinogen. Trypsin helps break down proteins during digestion.
What are pancreatic juices, and what do they consist of?
Pancreatic juices are those secreted by the pancreas and released into the small intestine. Pancreatic juices consists of enzymes and proenzymes.
What is emulsification, and what is its function in the digestive system?
Emulsification is the process of mixing 2 substances that don’t usually mix but are forced to combine. It happens when tiny drops of lipid spread evenly in another. It breaks down larger lipids into smaller ones.
How is bile used as an emulsifier in the human body?
When you eat fatty foods, they don’t mix well with the watery digestive juices in your stomach. So the body uses bile to help break down the fat into tiny droplets, now the fat is broken down into smaller pieces.
Bile is produced in the _____ and transported to the _____________.
a) liver
b) gallbladder
Note: Bile, stored in the gallbladder, and pancreatic juice from the pancreas is finally added to the food in the duodenum via the Ampulla of Vater
Got it 🤔
What are the 3 parts of the small intestine?
Duodenum, Jejunum, and Ileum
What are villi, and what are their functions in the small intestine?
The small intestine consists of many fingerlike projections called ‘villi’, which increase the surface area for nutrient absorption.
