UNIT 2.3 - ENERGY AND ATP

Why is ATP not a good long-term energy store? Why don't cells store large quantities of ATP?

Due to the instability of its phosphate bonds ATP is therefore the immediate energy source of a cell

Why is ATP a better immediate energy source than glucose?

Each ATP molecule releases less energy than each glucose molecule. The energy for reactions is therefore released in smaller, more manageable quantities rather than the much greater, and therefore less manageable, release of energy from a glucose molecule. The hydrolysis/break down of ATP to ADP is a single reaction that releases immediate energy whereas glucose is a long series of reaction and therefor energy release takes longer.

What is ATP a monomer of? What type of monomer is it?

Typically related to the monomer of RNA ATP is a nucleotide

What is used to convert ATP to ADP?

Water (H20)

Explain how ATP stores energy?

- The bonds between the phosphate groups are unstable - Therefore have low activation energy and are easily broken - When they break they release a considerable amount of energy

What type of molecule is ATP?

A Phosphorylated macromolecule

The conversion of ATP to ADP is a reversible reaction. What must be added to ADP to reform ATP What enzyme will catalyse this reaction? What type of reaction is this (BESIDES REVERSIBLE)?

A inorganic phosphate needs to be added to ADP to reform ATP Enzyme used - ATP synthase This is a condensation reaction as water is being removed

What are the main components of adenosine ?

Adenine Ribose

What are the main components of adenosine monophosphate? (AMP)

Adenine Ribose Phospate group

What are the main components of adenosine diphosphate ? (ADP)

Adenine Ribose x2 Phosphate groups

What three components make up ATP?

Adenine - a nitrogen containing organic base Ribose - a sugar molecule with a 5-carbon ring structure ( pentose sugar ) that acts as a backbone to which the other parts are attached Phosphates - a chain of three phosphate groups

What does ATP stand for?

Adenosine triphosphate

What is the equation for ATP converted to ADP ( word and symbol )? What type of reaction is this? What enzyme is used to catalyse this reaction?

Symbol Equation ATP + (H20) > ADP + Pi + E Word Equation Adenosine triphosphate + water > Adenosine diphosphate + inorganic phosphate + energy This is a hydrolysis reaction The enzyme used to catalyse this reaction is ATP hydrolase

Where does energy that organisms require initially come from?

The Sun

The synthesis of ATP from ADP involves the addition of a phosphate molecule to ADP. What are the 3 ways this can occur? ( Think plants or animals and plants+animals )

in chlorophyll containing plant cells during photosynthesis (photophosphorylation) in plant and animals during respiration ( oxidative phosphorylation ) in plant and animal cells when phosphate group are transferred from donor molecules to ADP ( substrate-level phosphorylation )

What are the main roles of ATP? (Build on your answer for each reason)

metabolic processes - ATP provides energy needed to build up macromolecules from their basic units. Movement - Muscle contraction Active Transport - Movement of ions across a concentration gradient. Secretion - ATP I needed to form Lysosomes necessary for secretion of cell products Activation of molecules - Hydrolysis of ATP is used to phosphorylate other compounds in order to make them more reaction.