1.5-1.7- ATP and water

What does ATP consist of?

organic base adenine, ribose sugar and three inorganic phosphate groups

how is ATP synthesised?

by addition of ADP to an inorganic phospjaye

condensation reaction catalysed by ATP synthase

phosphorylation

addition of phosphate molecule

what does ATP synthesis require?

input of energy from a metabolic process and occurs during respiration

some ATP made in photosynthesis

how is ATP hydrolysed?

inorganic phosphate removed, energy released and ATP becomes ADP

covalent bonds linking these phosphate groups is unstable and is easily broken by enzyme ATP hydrolase in a hydrolysis reaction

what is the role of ATP in active transport?

energy required to move substances against a conc. gradient using a carrier proteins in plasma membranes

these protein pumps are also ATP hydrolase enzymes, since they catalyse splitting of ATP to ADP and Pi and use the energy released to change shape and pump the molecule

what is the role of ATP in exocytosis?

energy required to make vesicles which are membrane bound spheres synthesised by the golgi body ans used to package large molecules prior to secretion from cells

energy also required to bring large molecules into cells (endocytosis)

what is the role of ATP in biosynthesis?

energy is required to make polymers from monomers e.g synthesis of proteins by condensation of amino acids, or new DNA molecules by condensation of nucleotides before cell division

What is the role of ATP in movement?

energy required to muscle contraction

what is the role of ATP in the activation of other molecules?

ATP can transfer its phosphate group to other molecules, phosphorylating them and making them more reactive e.g glucose requires phosphorylation at the start of the respiration to reduce the activation energy of the reaction

how is ATP useful in many biological processes?

hydrolysis of ATP releases energy in small manageable amounts

formed in single reaction, makes energy immediately available

can be reformed again

soluble- easily move inside cells

phosphorylates substances- makes them more reactive

what are the properties of water?

metabolite in condensation and hydrolysis reactions

solvent so metabolic reactions can occur + substances can be transported

high specific heat capacity- buffer changes in temp

large latent heat of vapourisation- cooling effect thru evaporation

strong cohesion between water molecules so supports columns of water in plants and provides surface tension supporting smaller organisms

role of iron ions?

binds with oxygen in haemoglobin, allows it to be transported around the body

how does H+ determine pH?

the more H+ present, the lower the pH- more acidic

enzyme controlled reactions affected by pH