enzyme action 4.1

Question 1

why are enzymes important

Answer 1

most of the processes necessary to life involve chemical reactions, and these reactions need to happen very fast.

in a lab there would need to be very high temp and pressure which would damage the cell, instead enzymes catalyse the reactions

Question 2

what are enzymes

brief

Answer 2

enzymes are biological catalysts. That are globular proteins

Question 3

what are the reactions required for growth called

Answer 3

• anabolic (building up) reactions

Question 4

when energy is released from large organic molecules like glucose, what are the reactions called

Answer 4

they are catabolic (breaking down) reaction. Catabolic reactions are also catalysed by enzymes

Question 5

what do many enzyme names end in

Answer 5

-ase

Question 6

what is metabolism

Answer 6

metabolism is the sum of all the different reactions and reaction pathways happening in a cell or an organism,

Question 7

what is Vmax

Answer 7

maximum rate of reaction brought about by enzymes

Question 8

what do molecules need to do for a reaction to occur

Answer 8

For a reaction to happen, molecules need to collide in the right orientation.

Question 9

what is meant by specificity of an enzyme

Answer 9

An enzyme catalyses a specific reaction

Question 10

what is activation energy

Answer 10

the energy needed for a reaction to start

Question 11

how do enzymes effect activation energy

Answer 11

Enzymes help the molecules collide successfully, and therefore reduce the activation energy required

Question 12

what are the 2 hypotheses for how enzymes help molecules collide successfully

Answer 12

lock and key hypothesis

induced fit hypothesis

Question 13

what is an active site

Answer 13

An area within the tertiary structure of the enzyme has a shape that is complementary to the shape of a specific substrate molecule

Question 14

what is the lock and key hypothesis

Answer 14

in the same way that only the right key will fit into a lock, only a specific substrate will ‘fit’ the active site of an enzyme

Question 15

what is it called when the substrate is bound to the active site

Answer 15

an enzyme-substate complex

Question 16

what occurs to the molecules involved in the enzyme-subsrate complex and what is produced as a result

Answer 16

The substrate or substrates then react and the product or products are formed in an enzyme-product complex. The product or products are then released, leaving the enzyme unchanged and able to take part in subsequent reactions

Question 17

what does the enzyme actually do to the substrate in the substrate-enzyme complex

Answer 17

The R-groups within the active site of the enzyme will also interact with the substrate, forming temporary bonds.
These put strain on the bonds within the substrate, which also helps the reaction along

Question 18

what is the induced fit hypothesis

Answer 18

evidence from research into enzyme action suggests the active site of the enzyme actually changes shape slightly as the substrate enters

Question 19

how does the substrate and the enzyme interaction when forming the enzyme-substrate complex for the induced fit hypothesis

Answer 19

upon inital binding bonds are weak, but they initiate changes to teritary structure of active site that work to break bonds in the substrate

Question 20

what are enzymes that act within cells called

Answer 20

intracellular enzymes

Question 21

what enzyme breaks down hydrogen peroxide (H202)

and in which organisms

Answer 21

catalase found in both plants and animals

Question 22

what do reaction within cells need

Answer 22

All of the reactions happening within cells need substrates (raw materials) to make products needed by the organism

Question 23

what type of enzyme breaks down the large nutrient molecules in the process of digestion

Answer 23

extracellulcar enzymes, they work outside the cell that made them

in some organisms like fungi they work outside the body

Question 24

what are some examples of extracellular enzymes in the human body

Answer 24

examples of extracellular enzymes involved in digestion in humans are amylase and trypsin

Question 25

how do single celled organisms use extracellular enzymes

Answer 25

single-celled organisms, such as bacteria and yeast, releasing enzymes into their immediate environment to break down larger molecules like protein into smaller molecules like amino acids and glucose that can be reabsorbed by the organism

Question 26

where does the digestion of starch start and where does it continue to

Answer 26

the digestion of starch begins in the mouth and continues into the small intestine

Question 27

where is amylase found

Answer 27

amylase is produced by the salivary glands and the pancreas. It is released in saliva into the mouth and in pancreatic juice into the small intestine

Question 28

where is maltase found in the body

Answer 28

maltase is present in the small intestine

Question 29

what is trypsin and what is its function

Answer 29

• trypsin is a protease enzyme
• ^it catalyses the digestion of proteins into smaller peptides

Question 30

where is trypsin produced

Answer 30

trypsin is produced in the pancreas and released with the pancreatic juice into the small intestine, where it acts of proteins.