ATP Flashcards
What does ATP stand for?
Adenosine triphosphate
What is the law of conservation of energy?
Energy can’t be created or destroyed but may be converted from one form to another
What is energy?
The capacity to do ‘work’
What major processes require energy?
Muscle Contraction
Active transport
Synthesis of organic molecules
nerve transmission
In which molecules internal membranes is ATP produced?
Mitochondria and Chloroplasts
What enzyme is needed to hydrolyse ATP?
ATP synthase
When ATP is hydrolysed what is produced?
ADP + Pi
What does ATP allow active transport to do?
enable movement of specific ions or molecules across protein pumps
In Chemiosmotic theory electrons flow through a series of carriers what are they called?
The Electron Transport Chain
What is pumped into the intermembrane space? via what?
Protons via proton pumps
how do protons flow across the membranes?
down a concentration gradient through stalked particles
what is chemiosmosis?
the movement of an ion through a semi-permeable membrane
What type of reaction is the formation of ADP + Pi from ATP?
Exothermic
Why is ATP not stored?
a highly active cell may use 2 million per second, so no need to store it
Compare ATP structure with that of a DNA nucleotide
ATP is triphosphate (has 3 phosphates) DNA nucleotide only 1
ATP has base Adenine, DNA nucleotide can have bases Adenine, Thymine, Cytosine, or Guanine
ATP has sugar ribose, DNA nucleotide has sugar Deoxyribose
What is ADP?
Adenosine Diphosphate
How much energy is released when a phosphoanhydride bond is broken?
30.6 KJ mol/bond
What is Pi?
Inorganic Phosphate
What is AMP?
Adenosine Monophosphate
What happens in cell respiration?
ADP and Pi are recombined to form ATP
What type of reaction is the recombination of ADP and Pi? What bond is formed?
endothermic, requires energy to form phosphoanhydride bond
What is the addition of phosphate to a molecule called?
Phosphorylation
What makes up a hydrogen atom?
a single proton and electron
How does hydrogen contribute to ATP production?
energy released from H+ and e- moving goes to make ATP
Where is ATP produced?
across the internal membranes of both mitochondria and chloroplasts
Compare Photosynthesis and Respiration
Both produce ATP
Respiration converts Glucose and Oxygen into Carbon Dioxide and Water and ATP
Photosynthesis converts Carbon dioxide and Water into Glucose and Oxygen and ATP
In photosynthesis ATP is generated through light energy to form organic molecules
In respiration ATP is obtained through the breakdown of organic molecules
Compare breakdown of ATP to glucose
Hydrolysis of ATP to ADP involves a single reaction
Breakdown of glucose involves several steps
Only one enzyme is needed to hydrolyse ATP (ATP synthase)
Many enzymes needed to break down glucose
Compare energy release from ATP with glucose
ATP releases small ‘packets’ of energy, where and when needed
glucose releases large amounts of energy, some of which may be lost as heat
ATP provides a common source of energy for all chemical reactions in all cells, for all living organisms
Compare glucose and ATP’s ability to pass through a membrane
ATP is soluble and can pass between cell organelles.
Glucose requires an intrinsic protein
What are the roles of ATP?
synthesis of polymers
active transport
muscle contraction
nerve transmission
exocytosis
What does active transport enable?
movement of specific ions or molecules across protein pumps
How is ATP involved in nerve transmission?
Provides energy for active transport of ions across the nerve cell membrane via Na+/K+ pump
What is ATP production in mitochondria called?
Oxidative Phosphorylation
What is ATP production in chloroplasts called?
Photophosphorylation
Describe the 5 steps in the chemiosmotic theory of ATP synthesis
- electrons flow through the electron transport chain (carriers in membrane
- energy released is used to pump protons (H+) into the intermembrane space (via proton pumps)
- this raises the proton concentration in the intermembrane space
- protons flow across the membranes down a concentration gradient through the enzyme ATP synthetase (stalked particles)
- energy released is used to synthesise ATP from ADP & Pi
