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Enzyme Structure

1) Enzymes are made up of amino acids

2) Enzymes are chains of amino acids that fold into unique shapes to fit a substrate

3) Lock and key: the chemicla reacts is the substrate (key) and it fits into the enzymes active site (lock)

4) Activation energy- the minimum amount of energy required for a reaction to take place         

enzyme-substrate complex- a temporary molecule formed when an enzyme comes into perfect contact with it's substrate

active site- area of an enzyme that a substrate molecule can fit into

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Enzymes and Digestion

1) The Frech Chemisy Anselme Payen

2) It helps in the digestion and absorption of fat and eliminates waste products from the body

3) Carbohydrase-carbohydrate-simple sugar, glucose                                                                         They're made in the salivary glands, the Pancrease, The small intestine                                           The preffered pH is 7

4) Lipids-lipase-glycerol and fatty acids                                                                                                 They are made in the pancrease and small intestine                                                                           The preffered pH is 7                                                                                                                          

5) Proteins-proteases-amino acids                                                                                                       They are made in the stomach, the pancreas, the small intestine                                                        The preffered pH is 7

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Organisations in Animals

1) Epithelial, Glandular, Muscular

2) You describe and explain the trend in the graph and what you see

3) The surface of the small intestine wall is folded, and has projections called villi . The epithelial cells that cover each villus themselves have projections called microvilli . These all increase the surface area over which digested food.

4) Glands-Produce digestive juices                                                                                                    Stomach and small intestine- digests food                                                                                           Liver- produces bile                                                                                                                              Small intestine- absorbs soluble food molecules                                                                                  Large intestine- absorbs water from undigested food                                 

5) Tissue- a group of similar cells that work together to carry out a particular function                            Organ- a group of different tissues that work together to perform a certain function                          Organ system- a group of organs working together to perform a particular function


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Factors affecting Enzymes

1) The five factors: temperature, pH, enzyme concentration, substrate concentration, and the presence of any inhibitors or activators.

2) They affect the speed of an Enzymes action e.g. the concentration of the enzyme or substrate and the temperature

3) denaturing- When the shape of an enzyme is changed so it's no loner functional.                          Denaturing is partially or fully reversible                                                                                               When enzymes denature they are no loner active or fully functional

4) Catalyst- A substance that increases the rate of chemical reaction                                                   Substrate- the surface on which an organism lives                                                                             Enzyme-  proteins that act as catalysts within living cells


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Food tests

1) Reducing sugar-   Add Benedict’s reagent to the food and boil in a water bath it's intially blue if there's a positive result it'll turn red

Starch- Add iodine reagent to the food it's intially yellow-brown if the result is positive it'll turn blue-black

Protein/amino acids- Add Biuret reagent to the food it's intially blue if there's a positive result it'll turn lilac/purple

Fat- Add ethanol to the food to dissolve the fat then add water it's intially colourless if there's apositive result it'll turn into a white emulsion



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