Organisation - Digestion
Name all the organs in the digestive system?
- Salivary Glands ( in mouth )
- Stomach
- Liver
- Gall Bladder
-Pancreas
- Small Intestine
- Large Intestine
What do the salivary glands do?
Secrete saliva that contains amylase to digest carbohydrates
What breaks down starch and what is the product?
Starch is broken down by amylase to produce glucose
What does the stomach do?
Contains hydrochloric acid to kill bacteria and secretes protease enzyme to digest protiens
What breaks down protein and what is the product?
Protein is broken down by protease to produce animoacids
What does the small intestine do?
Absorbs small molecules into the blood. It contains all 3 enzyme types secreted by the pancreas by the pancreas including lipase to digest lipids/fats, protease to digest proteins, and amylase to digest carbohydrates.
What breaks down lipids and what are the products?
Lipids and broken down by lipase to produce glycerol and fatty acids
What is the lock and key theory?
The theory suggests that the substrates are the key, and the active site of the enzymes are the lock. It suggests that the active site (the "lock") is a specific shape so only pne type of substrate (the "key") can bind to it.
Why are digestive enzymes important?
Digestive enzymes are important as they break down large insoluble molecules into small soluble molecules which can be absorbed through cell membranes into the blood to be transported into the blood and used to build new molecules or for respiration.
What are amino acids used for?
To build proteins for growth
What is glucose used for?
Used to build carbohydrate e.g. glucogen as an energy store or in respiration
What are fatty acids and glycerol used for?
Used to make lipids as energy (fat) store
What affects the rate of enzyme action?
- Temperature - increase = increase in rate but too high causes enzymes to denature
- pH - pitside of optimum can denature the enzymes and slow down the rate
- Surface area - increase will increase the rate of reaction
What does denatured mean?
Active site changes shape so that so that it can no longer bind to the substrate
Where is bile produced?
In the liver
Where is bile stored?
In the gall bladder
What is bile?
Bile is a chemical (not an enzyme) that helps emulsify large fat droplets into small fat droplets to increase the surface area of the lipids so that lipase enzymes can bind and break down the lipids faster. It also helps neuralise stomach acid in the small intestine