8/12/2019 A3 Enzymes Nutrients Glossary

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Benedict's test for reducing sugars (glucose)

Enzyme characteristics:

B3 Enzymes / B4 Nutrition (4.1 Nutrients only)

Elements

Calcium

Minerals x x x

Iron

C

D

Importance to body Deficiency symptoms

Vitamins x x x

Proteins: amino acids to proteins Biuret test for protein

Importance of dietary fibre Importance of water in

diet

Vitamins and mineralsMicronutrient Food Sources

Fats: fatty acids and glycerol to fats and oils Emulsion fat test

Annotated diagrams Importance to body Food sources Food tests

Carbohydrates: simple sugars to starch / glycogen Iodine Starch test

B3 Enzymes:

Enzyme definition:

Effect of pH and temperature on enzyme activity:

annotated graphs:Yoghurt production

Bacterium:

Equation:

Waste product effects on milk:

>>

>

Effect of temperature on process:

Enzyme substrate complex diagram annotated

Nutrition definition:

Form 9 Revision

Amino acids Polypeptidechain- a short

chain of amino acidsProtein - a long chain of

amino acids.

Fats (triglycerides)Glycerol Fatty acids

Glucosemolecules

Maltose

sugar Starch & glycogen

2 7

A

B

D

C

A 0C-20C low kinetic energy few successful

collisionsB20C-40Cincreased kinetic energy more

successful collisions rate rx doubles every 10C

C 40C- optimum temperature most successful

collisions

Dabove 40Cenzymes active site changes shape,

substrate no longer fits enzyme denaturated

Blue curve = pepsin- pH of 2 is the optimum

pH for pepsin as it works in stomach which has

HCl; a pH of 9 will denature pepsin

Red curve = most enzymesa pH of 7 is the

optimum pH for salivary amylase which works

in mouth; a pH of 4 will denature amylase &

most enzymes e.g. lipase

Protein that acts as biological catalyst of chemical reactions; it speeds up the

reactions without being chemically changed: it can be used over & over again

To release energy through respiration for

immediate use;

Temporarily stored in liver/ muscles as glycogen;

Excess stored as fat

Carbon

Hydrogen

Oxygen

Carbon

Hydrogen

Oxygen

Carbon

Hydrogen

Oxygen

Nitrogen

Making cell membranes;

Insulation;

Long term energy storage

Growth & tissue repair;

Making enzymes;

Prevents kwashiorkor

Bread, rice, pasta,

potatoes

Sugar, honey

Vegetable oil,

butter, margarine,

cream, cheese, red

meat, egg yolks,

chocolate

Enzymes have an active site where substrate binds & undergoes a chemical reaction; each

is specific for each substrate, substrate fits exactly into this active site; they are affected by

temperature & pH, high temperatures & extreme pH denatures enzymes.

Meat, fish, beans,

eggs, nuts, lentils,

cheese

Food sample + 2drops iodine solution RESULT: + =blue/black;

- = Yellow/brown

1cmfood test tube + 1cmdistilled water + Benedicts solution enough

to cover food + heat tube for 3 min in 90 C water baths

RESULT: + =brick/orange; -= blue

1cmfood in test tube + 2cm ethanol & shake it, pour 1cm from test

tube 1 to test tube 2 + some distilled water & shake again

RESULT:+= cloudy; -= colourless

1cmfood in test tube + 1cm distilled water + drip 1cm of biuret

reagent + wait 3-5 min

RESULT: + = purple; -= blue

Lactobacillus bulgaricus

Lactose lactic acid + energy

Lowers the pH of milk milk proteins coagulate & form clumps milk separates

Clumps are called curds

Liquid part is called whey

The optimum temperature to produce yoghurt is 40C. At this temperature there is a significant growth of

bacteria which allows lactase enzyme to rapidly break down the lactose in milk into lactic acid, which

lowers its pH making it coagulate. Temperatures between 4 -30C produce no considerable change in the

pH of milk to making it coagulate, so it remains liquid & it does not has the texture of yoghurt.

Helps the alimentary canal work

properly. Stimulates peristalsis.

It helps to prevent constipation &

bowel/colon cancer.

Is used in body as solvent in which

chemical reactions take place; as a

solvent for waste matter; for

transporting substances around the

body; for keeping our body cool. A lack

of water can cause dehydration which

results in death after 3 days.

Oranges, lemons, green vegetables Needed for healing wounds, making collagen, helps to bond cells

rHelps body to absorb calcium from blood for making bones & teeth

Scurvy (bleed gums & internal organs)

Rickets in children; brittle bones in adults

Liver, eggs, beef, dark green vegetables

Milk & other dairy products, bread

Making haemoglobin, red pigment in blood which carries oxygen

Fish liver oil, milk, butter, eggs

For bones & teeth, for blood clothing

Anaemia, not enough oxygen delivered to tissues

Brittle bones & teeth, poor blood clothing

Lock & key model