Enzymes And Digestion Flashcards
What are enzymes?
They are proteins that are biological catalyst that speed up the rate of reactions without being used up themselves
How are enzymes specific?
Each active site has a unique shape that means that no other substrate can fit into it.
Enzyme- ?
Substrate-carbohydrates
Products- ?
Enzyme- carbohydrase
Substrate- carbohydrates
Products- glucose
Enzyme-?
Substrate- starch
Products- ?
Enzyme- amylase
Substrate- starch
Products- glucose
Enzyme-?
Substrate- proteins
Products- ?
Enzyme- protease
Substrate- protein
Products- amino acids
Enzyme- ?
Substrate- fat (lipids)
Products- ?
Enzyme- lipase
Substrate- fat (lipids)
Products- fatty acids and glycerol
How is the enzyme complementary to substrate?
The enzyme is complementary as it allows the substrate to fit into the active site
Why can enzymes be used over and over again?
Once the substrate fits into the , the reaction take place, and products leave active site
This means that the active site is free and ready to accept a new substrate molecule
So they can be used over and over again
What is an inhibitor? And why do they reduce the rate of reactions?
An inhibitor is a molecule that fits (loosely or partially) into the active site of an enzyme.
This means that the active site is blocked and the substrate cannot enter to be broken down as long as the inhibitor is there. Therefore, the rate of reaction is reduced by inhibitors.
What is digestion?
The breakdown of big, insoluble particles to small, soluble particles so they can be absorbed into the bloodstream.
Explain the function of the mouth in terms of digestion?
- Mechanical digestion by teeth
- Chemical digestion of starch by amylase
Explain the function of the stomach?
Makes gastric acid containing
- Protease enzyme (digests protein)
- Acid (optimum pH for protease/ kills germs)
Explain the function of the liver?
Makes bile (helps digest fat/neutralises acid)
Explain the function of the gall bladder?
Stores bile
Explain the function of the pancreas?
Makes enzymes
What is the function to duodenum (1st part of small intestine)?
Most digestion occurs here
What is the function of the ileum (2nd part of the small intestine)?
Absorption of food into blood
What is the function of the colon (large intestine)?
Water absorption
What is the function of the Rectum?
Stores faeces
What is the function of the anus?
Removes faeces
How is the ileum adapted for the absorption of food molecules?
- Large surface area - long;folded;villi
- Good blood supply
- Thin & permeable membranes
How is the villus adapted for absorption?
- shape increases surface area
- single layer of cells
- blood capillary network (absorbs products of digestion)
- lacteal (absorbs digested fat)
Describe the effect of temperature on enzymes?
As the temperature increases the rate of enzyme activity increases and the molecules have more energy therefore more collisions between enzyme & substrate
Above the optimum temperature the enzyme denatures and the shape of active site changed and the substrate cannot fit into active site and the enzyme no longer works
Describe the effect of pH on enzymes?
Either side of the optimum pH enzymes work less well because the pH changes the shape of the active site (denatured)
Explain the effect of enzyme concentration?
Increasing the concentration of enzymes only make a faster reaction until a certain point at where there is not enough substrate molecules for the enzymes
