Digestive System Flashcards
What are enzymes?
Proteins that control chemical reactions in all living organisms
What is the structure of an enzyme?
It’s made from long chains of amino acids folded into specific shapes
What are enzymes referred to as?
Biological catalysts
What binds to an enzymes active site?
A substrate
What does the lock snd key model state?
The active site of an enzyme fits the substrate perfectly like a locking key they are complementary
Rates of enzyme controlled reactions are controlled by what?
Temperature and pH
What happens if if the temperature is passed an enzymes optimum temperature?
It denatures
What does the optimum temperature mean for an enzyme?
They have more kinetic energy and I’m more likely to collide
How do you know if starch is present?
If iodine is added, it turns blue or black colour
How do you know if starch isn’t present?
Iodine turns it a brownie orange colour
How do you calculate rate of reaction?
Change in mass over change in time (draw a tangent)
Where and how are digestive enzymes made?
They may buy specialised cells in the glands and lining of the gut
What do the digestive enzymes do?
They speed up the breakdown of large and soluble food molecules into smaller soluble molecules to be digested into the bloodstream
What are the three main digestive enzymes?
Amylase, protease and lipase
What does secreted mean?
Released
What are the two ways to digest food?
Mechanically, e.g. using your teeth or chemically
Where is Amylase found and what does it breakdown?
In saliva, it breaks down starch into simple sugars like glucose or maltose
What is the test for proteins? And if proteins are present what colour will they go?
The biuret solution and it will turn purple
What is the test for lipids? And if they are present what colour does it go?
Sudan IIII and it will turn the surface of the water into a red stained oil layer
What is the test for sugars and what colour will it go?
Benedict Regent and you will heat it up for two minutes it will turn yellow green or red depending on the concentration
Where is amylase produced?
The pancreas and salivary glands
Amylase sites of action
Small intestine and the mouth
Amylase is a type of…
Carbohydrase
What does protease do?
Breakdown protein into amino acids
What are the action sites for protease?
Small intestine and stomach
Where is protease produced?
Small intestine pancreas and stomach
What does lipase do?
Breaks lipids into fatty acids and glycerol
Where is lipase produced?
Small intestine and pancreas
Where is lipase produced?
Small intestine and pancreas
Enzymes in the small intestine operate best in what kind of conditions
Alkaline
What does bile do?
Neutralises acid from the stomach so the enzymes don’t denature
What is the emulsification ?
When Bile breaks up fats into tiny droplets
Where is Bile stored?
In the gall Bladder
Where is Bile produced?
The liver
Role of digestive system
Exchange substances with the environment
Role of large intestine
Absorb water from undigested food
Purpose of villi in small intestine
Large surface area, short diffusion distance and they take nutrients from food
Difference between simple and complex carbohydrates
Simple- 1 or 2 sugar units joined together
Complex- long chains of simple sugars
Function of proteins in body
Make up tissues, hormones, antibodies and enzymes
