3.1 Importance Of ATP

Question 1

What is chemiosmosis

Answer 1

Flow of protons down an electrochemical gradient through ATP synthetase coupled with the synthesis of ATP from ADP + Pi

Question 2

Name of ATP

Answer 2

Adenosine triphosphate

Question 3

Why can ATP be referred to as the universal energy currency

Answer 3

Used in all living cells and organisms for all/most reactions

Question 4

How does ATP release energy

Answer 4

In small quantities (30.6kJmol-1) through a one step reaction using ATPase where the high energy bond between the second and third phosphate is hydrolysed

Question 5

Some reactions ATP is used for

Answer 5

Protein synthesis
Muscle contraction
Active transport
Mitosis

Question 6

Where does the electron transport chain occur in the chloroplast

Answer 6

Thylakoid membrane

Question 7

Where does the electron transport chain occur in the mitochondria

Answer 7

Cristae

Question 8

Where is the electrochemical gradient in the chloroplast

Answer 8

From the thylakoid space to the stroma

Question 9

Where is the electrochemical gradient in the mitochondria

Answer 9

From intermembrane space to the matrix

Question 10

Co-enzyme involved in electron transport chain of chloroplast

Answer 10

NADP

Question 11

Co-enzyme involved in electron transport chain of mitochondria

Answer 11

NAD
FAD

Question 12

Final electron acceptor in electron transport chain of chloroplast

Answer 12

Cyclic - chlorophyll a
Noncyclic - NADP and H+

Question 13

Final electron acceptor in electron transport chain of mitochondria

Answer 13

Oxygen

Question 14

What is phosphorylation

Answer 14

Addition of a phosphate group or ion to a molecule

Question 15

What is oxidative phosphorylation

Answer 15

Addition of phosphate ion to ADP using energy from electron loss

Question 16

When does oxidative phosphorylation occur

Answer 16

During electron transport chain

Question 17

What is photophosphorylation

Answer 17

When energy that powers the proton pumps and the Electron Transport Chain in chloroplasts comes from LIGHT

Question 18

When does photophosphorylation occur

Answer 18

When ATP is synthesised in chloroplasts

Question 19

What is substrate level phosphorylation

Answer 19

When phosphate groups are transferred from donor molecules

Question 20

When does substrate level phosphorylation occur

Answer 20

Glycolysis and Krebs

Question 21

What kind of oxygen requirements does yeast have

Answer 21

Facultative anaerobe

Question 22

What is the enzyme used in dehydrogenation and what does it reduce

Answer 22

Dehydrogenase
Reduces NAD to NADH2

Question 23

What does dehydrogenase do

Answer 23

Removes hydrogen atoms from intermediates in both respirations and transfers them to hydrogen acceptors such as NAD and FAD

Question 24

What are the H acceptors in respiration and what acts as an artificial hydrogen acceptor

Answer 24

NAD FAD

methylene blue

Question 25

What is the colour change of methylene blue when it is reduced

Answer 25

Blue to colourless

Question 26

What can be measured in the investigation of dehydrogenase activity

Answer 26

The time taken for indicator to change colour

Question 27

Control for the investigation of dehydrogenase activity

Answer 27

Boil the yeast and let it cool
This denatures the enzyme so when repeated there is no colour change as dehydrogenase is denatured
This proves it is the independent variable that is responsible for the difference in the results

Question 28

Hazard risk and control method when handling yeast

Answer 28

• yeast is a fungus which could cause an eye infection
• when measuring the yeast it could splash into your eyes
• wear safety goggles and wash hands prior to contact with yeast

Question 29

Hazard risk and control method when using glass

Answer 29

• can be sharp if broken
• cut yourself whilst handling it
• clear up any broken glass quickly and take care when handling it

Question 30

Area of uncertainty in investigation of dehydrogenase activity and improvement

Answer 30

• subjective reading when deciding when the colour of methylene blue has gone
• use a colorimeter and see the time it takes for the solution to reach a pre-determined absorbance which turns it into an objective reading