ATP

Question 1

what is ATP

Answer 1

-adenosine triphosphate

Question 2

describe the structure of ATP

Answer 2

-ribose bound to a molecule of adenine (base) and 3 phosphate groups
-nucleotide derivative (modified nucleotide)

Question 3

describe how ATP is broken down

Answer 3

-ATP + water -> ADP + Pi
-hydrolysis reaction, using a water molecule
-catalysed by ATP hydrolase (enzyme)

Question 4

what does ADP stand for

Answer 4

-adenosine diphosphate

Question 5

what does Pi stand for

Answer 5

-inorganic phosphate

Question 6

give two ways in which the hydrolysis of ATP is used in cells

Answer 6

-coupled to energy requiring reactions within cells (releases energy) eg active transport
-inorganic phosphate released can be used to phosphorylate (add phosphate to) other compounds, making them more reactive

Question 7

describe how ATP is resynthesised in cells

Answer 7

-ADP + Pi -> ATP (+water)
-condensation reaction, removing a water molecule
-catalysed by ATP synthase (enzyme)
-during respiration and photosynthesis

Question 8

suggest how the properties of ATP make it a suitable immediate source of energy for cells

Answer 8

-releases energy in (relatively) small amounts/ little energy lost as heat
-single reaction/ one bond hydrolysed to release energy (so immediate release)
-cannot pass out of cell