5A- Photosynthesis, Respiration And ATP Flashcards
Why do biological processes need energy?
Plant and animal cells need energy for biological processes to occur.
Plants need energy for things like photosynthesis, active transport, DNA replication, cell division and protein synthesis.
Animals need energy for things like muscle contraction, maintenance of body temperature, active transport, DNA replication, cell division and protein synthesis.
How does photosynthesis store energy as glucose?
Energy from light is used to make glucose from H2O and CO2 (the light energy is converted to chemical energy).
6CO2 + 6H2O + Energy —> C6H12O2 + 6O2
Energy is stored in the glucose until plants release it by respiration.
How do animals obtain glucose?
By eating plants or other animals, then respite the glucose to release energy.
What is it called when plants and cells release energy from glucose?
Respiration
What is the energy used for in respiration?
To power all biological processes.
What are the two types of respiration?
Anaerobic
And
Aerobic
What does aerobic respiration produce?
CO2, H2O and energy.
C6H12O6 (glucose) + 6CO2 —> 6CO2 + 6H2O + Energy.
What does anaerobic respiration produce?
In plants and yeast it produces ethanol and CO2 and released energy.
In humans it produces lactate and released energy.
How is ATP the immediate source of energy in the cell?
A gel can’t get energy directly from glucose.
In respiration energy released from glucose is used to make ATP. It carries energy to cells where it is needed.
ATP is synthesised via condensation reactions between ADP + Pi. The energy is stored as chemical energy in the phosphate bond. ATP synthase catalysed this reaction.
ATP diffuses into cells where it’s hydrolysed back into ADP and Pi. ATP hydrolyse catalysed the reaction.
What specific properties does ATP have that make it a good energy source?
It stores and released only a small amount of energy, so no energy is wasted as heat.
It’s small and soluble so if can easily be transported around the cell.
It’s easily broken down so energy can easily released.
It can quickly be remade.
It can make other chemicals more reactive by transferring one of its phosphate groups to them in phosphorylation.
ATP can’t pass out of the cell, so the cell always has an immediate supply of energy.
What is a metabolic pathway?
A series of small reactions controlled by enzymes.
What is phosphorylation?
Adding phosphate to a molecule.
What is Photoionisation?
When light excites electrons in an atom giving them more energy and causing them to be released, causing the atom to become a positively charged ion.
What is photolysis?
The splitting of a molecule using light energy.
What is photophosphorylation?
Adding phosphate to a molecule using light.
