ATP

Question 1

what is the immediate source of energy in organisms?

Answer 1

ATP

Question 2

Where ATP molecules derived from?

Answer 2

nucleotide

Question 3

what does an ATP molecule consist of?

Answer 3

• the organic base adenine
• ribose sugar
• three phosphate groups

Question 4

what is the addition of a phosphate molecule know as?>

Answer 4

phosphorilation

Question 5

describe how ATP is synthesised

Answer 5

the addition of ADP to an organic phosphate

a condensation reaction catalysed by the enzyme ATP synthase

Question 6

what enzyme is involved in synthesising ATP?

Answer 6

ATP synthase

Question 7

where is the useful energy stores in the ATP molecule?

Answer 7

the phosphate-phosphate bonds

Question 8

why is the energy mainly stored in the phosphate-phosphate bonds of ATP?

Answer 8

the covalent bond linking them is unstable and easily broken by ATP hydrolase

Question 9

give the role of ATP

Answer 9

• active transport
• exocytosis
• synthesis of substances
• movement
• activation of other molecules

Question 10

Describe how ATP is used in the process of active transport

Answer 10

• energy is required to move molecules against the concentration gradient using carrier proteins

Question 11

Describe how ATP is used in the process of exocytosis

Answer 11

energy is required to make vesicles which are membrane bound spheres synthesised by the Golgi body

Question 12

Describe how ATP is used in synthesising substances

Answer 12

energy is required to make large molecules into smaller ones

Question 13

Describe how ATP is used in the process of movement

Answer 13

-energy is required for muscle contraction

Question 14

Describe how ATP is used in the activation of other molecules

Answer 14

ATP can transfer its phosphate group to other molecules

making them more reactive

Question 15

why is ATP only an immediate source of energy?

Answer 15

the instability of the phosphate bonds

Question 16

ATP is hydrolysed into …

Answer 16

ADP + Pi

Question 17

why is ATP more useful than glucose as an immediate energy source

Answer 17

• the breakdown of ATP to ADP and phosphate is a single reaction, making energy immediately available. the breakdown of glucose is a complex reaction involving several stages
• ATP is soluble and easily moved around inside cells, but cannot pass through cell membranes
• the breakdown of an ATP molecule releases a small amount of energy, the breakdown of glucose release a lot of energy maybe more than is required so a lot of energy is wasted