importance of ATP

Question 1

What is ATP known as and why

Answer 1

• the universal energy currency
• used in all cells to drive their reactions

Question 2

When is ATP made give examples

Answer 2

• when energy becomes available eg in respiration and light dependedent reactions of photosynthesis

Question 3

How is ATP used and for what

Answer 3

• it is broken down when the cell needs energy
• such as in biosynthesis, muscle contraction and powering the membrane, Na+/K+ pumps

Question 4

How is ATP suited to its role

Answer 4

• is inert
• can pass out of mitochondria into the cytoplasm
• releases energy efficiently
• releases energy in usable quantaties and little is wasterd a heat
• easily hydrolysed to release energy
• readily reformed by phosphorylation

Question 5

Describe the pathway of electrons derived from hydrogen atoms

Answer 5

• transferred from a donor molecule to a recipient
• then a sequence of reactions transfers the electrons from one molecule to the next along a chain
• each transfer is a redox reaction in which one molecule is oxidisedand the next in this sequence is reduced
• oxidation reactions make energy available and this energy is eventually used to synthesis ATP

Question 6

Describe the movement of protons dervied from hydrogen atoms

Answer 6

• energy released via oxidation pumps the protons from the hydrogen atoms across a membrane so that they are more concentratied on one side of the membrane than the other
• the difference in the concentration of protons and the charge on either side of the membrane induces and electrochemical gradient and is a source of potential energy
• protons flow back down this gradient ina process called chemiosmosis through the enzyme ATP synthetase
• the energy they releasse as they do is converted into the chemical energy ATP