3.11 ATP

Question 1

What is ATP?

Answer 1

nucleotide composed of:

• a nitrogenous base (adenine)
• a pentose sugar (ribose)
• 3 phosphate groups.

Universal energy currency for cells.

Question 2

What do cells require energy in the form of ATP for?

Answer 2

1. SYNTHESISING MOLECULES (e.g protein synthesis)
2. TRANSPORT (e.g active transport)
3. MOVEMENT (protein fibre contractions)

Question 3

What is the equation for hydrolysis of ATP?

Answer 3

ATP + H2O ⟶ ADP + Pi + 30.6kJ

Adenosine triphosphate + Water ⟶ Adenosine diphosphate + Inorganic phosphate + 30.6kJ

Question 4

What is the name of the reaction where ATP is converted to ADP?

Answer 4

hydrolysis

Question 5

What is the name of the reaction where ADP is converted to ATP?

Answer 5

phosphorylation (a type of condensation reaction)

Question 6

What properties of ATP make it well-suited as an energy store?

Answer 6

• SMALL - easy extra/intracellular movement
• WATER-SOLUBLE - energy-requiring processes occur in aqueous environment of cytoplasm
• RELEASES ENERGY IN MANAGEABLE QUANTITIES - amount of energy released suited to cellular needs, ∴ less wasted as heat
• EASILY REGENERATED - phosphorylation

Question 7

Why is ATP a bad long term energy store?

Answer 7

ATP is very unstable, ∴ cannot remain for long period of time,

∵ bonds between phosphate 2 + 3 is very weak.

Question 8

Unlike ATP, what is a good long term energy store?

Answer 8

fats, carbohydrates, e.t.c

Question 9

Why is ATP a good short-term energy store?

Answer 9

Weak bonding between 2^nd + 3^rd phosphate makes it too unstable for long term storage.

ATP present for a short amount of time before being hydrolysed to release energy.

Question 10

What is the sugar present in ATP?

Answer 10

ribose, a pentose sugar

Question 11

What is the nitrogenous base present in ATP?

Answer 11

adenine

Question 12

What does an ATP nucleotide consist of?

Answer 12

1. nitrogenous base adenine
2. pentose sugar ribose
3. 3 phosphate groups