Digestive System Flashcards
What is the digestion?
Digestion is the process of breaking down food and drink into smaller molecules so the body can absorb and use them for energy.
The 4 main processes in the digestive system
Ingestion: This happens when you take food or fluids into your body through your mouth by drinking or eating it.
Digestion: This is the process of breaking large food pieces down and processing fluids into particles that are small enough to be absorbed and pass through cell membrane.
Absorption: When the digested particles move into the cells of the digestive tract and move to bloodstream from where they are carried to all cells in the body.
Egestion: Removes any undigested or unwanted particles from the body
Order of Disgestive System
The mouth, oesophagus, stomach, small intestine, pancreas, liver, gallbladder, duodenum, large intestine, and anus.
Pancreas Enzymes
Protease - Proteins
Lipase – Lipids
Amalyase – carbohydrates
Sodium Bicarb – Neutralise stomach acid
Mechanical Digestion
It involves physically breaking down food into smaller chunks to be chewed and mixed with saliva before swallowing.
Mechanical digestion occurs in:
1.The mouth in the form of chewing.
2.The stomach when it churns.
3.The small intestine with the action of bile.
Chemical Digestion
It’s breaking down of food into its building blocks by substances called enzymes.
Food is made up of chemical compounds (large molecules):
- Proteins
- Carbohydrates
- Lipids / Fats
Which food is digested in the mouth (state the enzyme involved)?
Starch and fats are digested in the mouth by the enzymes amylase and lingual lipase, which are found in saliva.
How is food moving through the oesophagus?
Food moves through the esophagus by a series of wave-like muscle contractions called peristalsis
What food is digested in the stomach? Describe the different substances found in
gastric juice with their function.
The stomach digests proteins, and gastric juice contains hydrochloric acid and enzymes that break down food.
What are the substances secreted into the duodenum? What is the function of bile and
sodium bicarbonate? Where is bile stored?
The duodenum receives bile, pancreatic juice, and alkaline mucus. Biles functions to break down fats into smaller droplets during digestion by a process called emulsification, while sodium bicarbonate helps neutralise stomach acid in the small intestine. Bile is stored in the gallbladder.
Describe the function of the pancreas and any substances that it is responsible for
secreting and their purpose.
It produces digestive enzymes to break down food in the small intestine, and it secretes hormones like insulin and glucagon to regulate blood sugar levels.
Describe the digestive processes in the small intestine.
The further breakdown of food particles into smaller molecules by enzymes from the pancreas and bile from the liver, followed by the absorption of these nutrients through the intestinal lining.
Describe the absorption of nutrients in the jejunum and ileum.
The jejunum and ileum are parts of the small intestine that absorb nutrients from digested food. The jejunum absorbs most nutrients, while the ileum absorbs nutrients that the jejunum doesn’t.
What are the products of digestion? Where and how are they sent?
These include glucose, amino acids, fatty acids, vitamins, minerals, and water into the small instestine.
What happens in the large intestine?
Absorbs water and changes the waste from liquid into stool.
