3.11 ATP

Question 1

Give examples of processes that require energy

Answer 1

Muscle contraction, cell division and transmission of nerve impulses

Question 2

What are the 3 main types of activities that cells require energy for? Elaborate on them

Answer 2

Synthesis - of large molecules e.g. proteins

Transport - Pumping molecules/ions across cell membranes through active transport

Movement - Protein fibres in muscle cells that cause muscle contraction

Question 3

What supplies energy in cells?

Answer 3

ATP, adenosine triphosphate

Question 4

Describe the composition of ATP

Answer 4

A nitrogenous base, a pentose sugar and 3 phosphate groups. It is a nucleotide.

Question 5

How does the structure of ATP and nucleotides involved in structure of RNA and DNA compare?

Answer 5

In ATP, the base is always adenine, and has 3 phosphate groups instead of 1.
The sugar in ATP is ribose, same as in RNA nucleotides

Question 6

Why is ATP known as the universal energy currency?

Answer 6

It’s used for energy transfer in all cells of all living things

Question 7

How does ATP release energy? (intro)

Answer 7

• Energy is needed to break bonds + is released when bonds are broken
• Small amount of energy is needed to break the weak bond holding the last phosphate group in ATP
• A large amount of energy is released when the liberated phosphate undergoes other reactions in bond formation

Question 8

Why is energy release from ATP a hydrolysis reaction?

Answer 8

Water is involved in removal of phosphate group

Question 9

What is ATP hydrolysed into?

Answer 9

ADP, adenosine diphosphate, and a phosphate ion, releasing energy

Question 10

Why is ATP not a good long term store? What’s the better alternative?

Answer 10

1. ATP has unstable phosphate bonds

2. Fats and carbs

Question 11

Where does the energy to produce ATP come from?

Answer 11

The breakdown of fats and carbs through cellular respiration

Question 12

How is ATP produced from the break down of fats and carbohydrates?

Answer 12

By reattaching a phosphate group to an ADP molecule, through phosphorylation

Question 13

How is phosphorylation an example of a condensation reaction?

Answer 13

Water is removed

Question 14

Why is ATP a good immediate energy store?

Answer 14

Interconversion of ATP and ADP is constantly happening in all living cells, so cells don’t need a large store of ATP

Question 15

What are the 5 properties of ATP?

Answer 15

1. Small
2. Water soluble
3. Contains bonds ebtween phosphates with intermediate energy
4. Releases energy in small quantities
5. Easily regenerated

Question 16

Why is it an adaptation for ATP to be small?

Answer 16

ATP can easily move into, out of and within cells

Question 17

Why is ATP being water soluble an adaptation?

Answer 17

Energy-requiring processes happen in aqueous environments

Question 18

Why does ATP containing bonds between phosphates with intermediate energy an advantage?

Answer 18

Large enough to be useful for cellular reactions but not so large that energy is wasted as heat

Question 19

ATP releases energy in small amounts: Why is this an adaptation?

Answer 19

1. Quantities are enough for most cellular needs

2. So energy isn’t wasted as heat

Question 20

ATP can easily regenerate: Why is this an advantage?

Answer 20

ATP can be recharged with energy