2.1.2m ATP Flashcards
What is cell respiration
The controlled release of energy from organic compounds to produce ATP
What is the main organic compound used for cell respiration
Carbohydrates (glucose), although lipids & proteins can also be digested
2 types of cell respiration
- Anaerobic respiration
- Aerobic respiration
What is anaerobic respiration
Involves the partial breakdown of glucose in the cytosol for a small yield of ATP
What is aerobic respiration
Utilises oxygen to completely break down glucose in the mitochondria for a larger ATP yield
Word equation for respiration
Glucose + Oxygen –> CO2 + Water + Energy
Symbol equation for respiration
C6H12O6 + 6O2 –> 6CO2 + 6H2O + ATP
What is ATP
Adenosine triphosphate is the energy-carrying molecule that provides the energy to drive many processes inside living cells
Structure of ATP
- ATP is another type of nucleic acid & hence it is structurally very similar to the nucleotides that make up DNA & RNA
- One molecule of ATP contains 3 covalently linked phosphate groups - which store potential energy in their bonds
ATP and phosphate groups
Adenosine (a nucleotide) can be combined with 1, 2 or 3 phosphate groups:
- 1 phosphate group = Adenosine Monophosphate (AMP)
- 2 phosphate groups = Adenosine Diphosphate (ADP)
- 3 phosphate groups = Adenosine Triphosphate (ATP)
5 points
What do PLANTS need energy for
- Photosynthesis
- Active Transport (eg. to take in minerals via their roots)
- DNA replication
- Cell division
- Protein synthesis
6 points
What do ANIMALS need energy for
- Muscle contraction
- Maintenance of body temp
- Active Transport
- DNA replication
- Cell division
- Protein synthesis
How do plants get energy
Plants can’t get energy from glucose directly. It needs to be released from the glucose through respiration. This makes ATP
see slide 6-8 for dia of ATP
Functions of ATP
- ATP is the energy currency for the cell
- ATP stores energy for the cell & releases it when energy is needed
When does ATP break down
ATP breaks down when there is a demand for energy
Reaction for ATP
ADP + Pi + Energy <–> ATP
This reaction is reversible & is catalysed by the enzymes ATPase & ATP synthase
ATP is a…
…phosphorylated nucleotide
What happens when ATP is hydrolysed
When ATP is hydrolysed (to form ADP + Pi) the energy stored in the phosphate bond is released to be used by the cell
Cell respiration linked with ATP
Cell respiration uses energy stored in organic molecules to regenerate ATP from ADP + Pi (via oxidation)
see slide 11 for dia of ATP & ADP
BANGME
Uses of ATP
Biochemical processes that utilise ATP include:
- Biosynthesis of macromolecules (eg. polymer assembly)
- Active transport (eg. endocytosis/exocytosis)
- Nerve transmission (eg. propagation of action potentials)
- Growth & repair (eg. mitotic division)
- Movement (eg. muscle contraction)
- Emission of light (eg. bioluminescence)
6 Points
WHY is ATP a good energy source
- Stores or releases small amounts of energy at a time so no energy is wasted as heat
- Can transfer energy by transferring a phosphate group
- Small & soluble - easily transported around the cell
- Easily broken down so energy can be released easily/rapidly
- Can’t pass out of a cell so the cell always has a supply of energy
- It can be quickly re-made. ADP+Pi–>ATP
Formation of ATP
ATP is synthesised via a condensation reaction between:
- ADP (adenosine diphosphate)
- an inorganic phosphate (Pi)
The energy needed to create ATP from ADP can come from the breakdown of glucose in respiration (dia on slide 14,16)
How does ATP work
- ATP diffuses to the part of the cell that needs energy
- Here, it is hydrolysed back into ADP & inorganic phosphate (Pi). Chemical energy is released from the phosphate bond & used by the cell. ATP hydrolase catalyses this reaction
- The ADP & inorganic phosphate are recycled & the process starts again
When does ATP form
ATP forms when chemical reactions release sufficient energy to bond a third phosphate group to ADP
(slide 20)
