How do these 2 species live together in perfect harmony?

Answer PhotosynthesisRespiration

This part of the module explores the relationship between photosynthesis and respiration. It looks at both processes in detail and the role played by ATP and coenzymes.

From your previous knowledge: What is photosynthesis?. The use of light energy to synthesise organic molecules. What is respiration? The process by which the energy in organic molecules is made available for other processes within an organism.

Both plants and animals breakdown these organic molecules to make ATP which is used as an energy source to carry out processes which are essential to life.

ATP stands for adenosine triphoshate. It is a small water soluble molecule that is easily transported around cells. ATP stores energy within the cell and releases it instantly for reactions that require energy. ATP breakdown (hydrolysis) is coupled with reactions which require ATP.

Is a phosphorylated nucleotide – sounds complicated but it is just a nucleotide with phosphate groups attached. You don’t need to learn the structure but it might be useful (particularly for extension):

It consists of: Adenine ( a base) Ribose (a sugar) PPP Now draw this at the top of page 4 of your booklet.

The formation of ATP requires energy. Formation of ATP is important to ensure a continuous supply of energy for the cell. Where does this energy come from? Light energy from the sun is converted by plants in to chemical energy during photosynthesis.

The organic molecules produced by photosynthesis are a store of chemical energy. This is converted into ATP in the cells during respiration.

The energy from respiration is used to convert ADP (adenosine diphosphate) and inorganic phosphate ….. into ATP Adenine ( a base) Ribose (a sugar) PP P ENERGY

i.e. ADP + P i + energy ATP

Breakdown of ATP involves releases energy. This can be used by energy- requiring reactions, but some energy is lost form the cell as heat energy.

The energy from respiration is released when ATP is hydrolysed to ADP (adenosine diphosphate) and P i Adenine ( a base) Ribose (a sugar) PPP ENERGY

Hydrolysis of ATP releases the stored energy: ATP ( + H 2 O) ADP + P i + energy e.g. for muscle contraction Why do you think this is known as hydrolysis?

Reversible reaction: ATP ADP PiPi HYDROLYSIS CONDENSATION Energy released for use by the cells Energy supplied from respiration

Uses of energy released by ATP Clue: Think about unit 1 – building molecules: ATP provides energy needed to build molecules up from basic units. E.g. polysaccharides from _________; polypeptides from __________; DNA / RNA from ____________.

Uses continued… Clue: Energy and exercise…. Energy from ATP allows protein muscle filaments to slide over each other to shorten the overall length of the muscle fibre allowing it to contract.

Uses continued…. Clue: Think about transport of substances across cell membranes. ATP provides energy to change the shape of the carrier protein, allowing substances to be transported against the concentration gradient.

Uses which are new to you.. ATP is needed to form lysosomes necessary for secretion of cell products.

Uses which are new to you.. When a phosphate molecule is transferred from ATP to another molecule it makes it more reactive and so lowers the activation energy of that molecule. This allows enzyme catalysed reactions to occur more readily.

Summary Questions 1.ATP is sometimes referred to as ‘an immediate energy source’. Explain why. 2.Explain how ATP can make an enzyme catalysed reaction take place more readily. 3.State three roles of ATP in plant cells.