Enzymes

Question 1

Enzymes

Answer 1

Enzymes are biological catalysts produced by all living cells. They speed up chemical reactions occurring in living organisms without being changed themselves.

Question 2

continued

Answer 2

Enzymes are proteins that living cells produce from amino acids obtained from the diet in animals, or manufactured in plants. Without enzymes, chemical reactions would occur too slowly to maintain life.

Question 3

Amylase

Answer 3

catalyses the breakdown of starch into sugars, mainly maltose. It is present in saliva, pancreatic juice and germinating seeds.

Question 4

Properties of enzymes

Answer 4

• Enzymes are specific, i.e. each type of enzyme catalyses only one type of reaction.
• Enzymes work best at a particular temperature known as the optimum temperature. This is about 37 °C for human enzymes.
• High temperatures denature enzymes, i.e. the shape of the enzyme molecules changes so that they are inactivated. Enzymes start to be denatured at about 40 °C to 45 °C.
• Enzymes work best at a particular pH known as the optimum pH. This is about pH7 for most enzymes

Extremes of acidity or alkalinity denature most enzymes

. * The action of enzymes is helped by certain vitamins and minerals, e.g. vitamin B1 helps the action of respiratory enzymes.

• The action of enzymes is inhibited by certain poisons, e.g. arsenic and cyanide.

Question 5

enzymes

Answer 5

change substrates into products

e.g. starch is the substrate the product is maltose and the enzyme is amylase

all enzymes have a dent in them called its active site. it is the exact size and shape to fit the molecule it breaks down, enzymes have an active site that perfectly fits its substrate, it is unique to that partiular kind of molecule, high temepratures change the shape of the enzyme and the active site no longer fits its substrate denaturing them

Question 6

sugars, fats and lipids, proteins

Answer 6

soluble
insoluble
some are soluble some are insoluble

carbs- C H O
fats- C H O
proteins- C H O N

Question 7

enzymes at optimum temp or high temperatures rather than low

Answer 7

collsion theory, able to bump in more frequently to its substrate in high temps due to increased kinectic energy, low temps does slower movements, not as rapid and random/erratic

Question 8

when asked to design a lab

Answer 8

pH- buffer solution
say how to observe results
to note colour changes
tables, graphs
calculations, etc

Question 9

enxymes in humans plants and bacteriua in hot spings

Answer 9

in humans optimum temperature of 37 body temp
in plants optimum temp of 28 to 30
in bacteria living in hot springs optimum temp as high as 75

Question 10

how to read graphs

Answer 10

as _____ increases the rate of the enzyme activity ____increases

as _____ increases the rate of the enzyme activity ____(perhaps rapidly)decreases

enzymes in humans start to denature at 40 to 45