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occurs in ...2 types ......
Definition ......
Equation? Equation?
Reactants Products Reactants Products
Extra Bonus Marks – Interestingly .....
• Define cellular respiration• Identify the energy source in cells and within
a molecule of ATP• Understand the link of ATP between
catabolic and anabolic reactions• Explain the process of phosphrylation• Potential for LO3
Cellular Respiration
Definition – Biochemical process by which energy-rich substrate molecules (foodstuff) are progressively broken down in enzymatic pathways to form adenosine triphosphate (ATP, high energy compound)
Foodstuff is usually glucose. Glucose is broken down in a series of enzyme controlled steps.
Hydrogen and high energy electrons are removed by dehydrogenase enzymes and used to yield ATP.
What is ATP?
Adenosine Triphosphate is a molecule composed of:
•1 x Adenosine (adenosine)•3 x inorganic phosphate (Pi)
Pi Pi PiAdenosine
Bonds contain energy 3 Inorganic Phosphate Groups
Guess what it would be called
with only 2 phosphates? 1
phosphate?
How could it release energy?
Energy Release & ADP
Adenosine Diphosphate
A Pi Pi Pi
Adenosine Molecule2 (di-) Inorganic
Phosphate molecules
1 Free Inorganic Phosphate Molecule
Energy released when bond breaks
When the terminal bond is broken energyenergy is released.
1 phosphate – adenosine monophosphate
Adenosine Triphosphate
Inorganic Phosphate molecules
Adenosine triphosphate (ATP)
• Main energy carrier molecule in the body (and all living things).
• ATP is used to transfer (links) the energy released (catabolic) from cellular respiration to synthetic pathways (anabolic) and other cellular processes where energy is required
Carbon dioxide and water
Glucose and oxygen
ATP
ADP +Pi
Amino acids
Protein
CELLULAR RESPIRATION
ENERGYTRANSFER
SYNTHETICPATHWAY
energy
energy
energy
energy
Which cells/processes need energy?
Uses of ATP in cells are:
Image source: http://www.dkimages.com
Sperm cell
Image source: http://www.sccollege.edu
Liver cell
Muscle cell
Image source: http://www.agen.ufl.edu
Nerve cellImage source: http://www.dkimages.com
• Muscle contraction• Driving chemical reactions• Active transport• Synthesis of e.g. protein• Transmission of nerve
impulses
Bioluminescence Demonstration - Luminescence is emission of light by a substance not resulting from heat; it is thus a form of cold body radiation
ADD ATP
Fluoro Fish
http://lem.ch.unito.it/didattica/infochimica/2008_GFP/Fish.html
Fluoro FishTaiwan's leading fluorescent fish industry has developed fluorescent fish that only glow from their blood vessels, takes so much ATP unable to have enough energy to reproduce.This technology could be used in the future to detect tumours in otherspecies.The Fluoro Fish are available at pet stores in all the US states, except California. They are marketed as GloFish and are available in Star-fire Red, Sunburst Orange, and Electric Green. They cost between $5-10.
The fluorescent zebra fish are created by microinjecting a fluorescent gene construct into fertilized zebra fish embryos. Australia, Canada, New Zealand and Europe prohibit the sale of genetically modified organisms, such as GloFish and they can not be purchased there.
Is it morally right to produce glowing fish for fish tanks?
Predict what would happen after 10 minutes? Why?
Demonstrate Questions
1. Calculate the percentage decrease
2. Why is it necessary to use percentage decrease in length in the comparison of the results?
3. What would be a good control for the experiment?
4. Muscle cells use energy for contraction. State one other cell activity that uses energy.
ATP
• 2 million molecules of ATP per second is needed to satisfy energy requirements for an active cell (such as liver/muscle etc)!
• How and where is it stored?
Other metabolic pathways (eg. stored as glycogen)
• Not stored! Rapid turnover of ATP molecules occurs continuously in a cell.
• Remains quite constant as the same amount is made that is used up (~50g)
• Cell conserves resources by only producing ATP when needed – it is another example of feedback inhibition .
• ATP and citric acid inhibit phosphofructikinaseGlucose (6C)
Intermediate 1
Intermediate 2
Intermediate 3
ATP
ADP+ Pi
ATP
ADP+ Pi
Phosphorylation at step 1
Phosphorylation at step 3 catalysed by phosphofructokinase
Irreversible step
AT
P
Citric Acid Cycle & Electron Transport Chain
ATP & citric acid inhibit phosphofructikinase! So go back to intermediate 2
Phosphorylation
• Phosphorylation is process which is enzyme controlled where a phosphate group (Pi) is added to a molecule.
ATP
ADP +Pi
Build-up energy required
Breakdown energy released
Phosphorylation
• Not only making ATP is called phophorylation (remember post translational modifiction of proteins), also when Pi from ATP given to another molecule in a metabolic pathway it makes them more reactive. For example glucose in glycolysis ......
• The phosphorylation of molecules to alter their reactivity.
ATP ADP +Pi
Glucose-6-phosphate (high energy)
Glucose
Effect of phosphorylase on phosphorylated substrate
• Investigation p100• Controls?• 3 minute intervals or 10 as shown below
Advantages of ATP
Instant source of energy in the cell
Universal energy carrier and can be used in many different chemical reactions
It is mobile and transports chemical energy to where it is needed IN the cell
Releases energy in small amounts as needed
Complete your exit slip before you go
ATP Exit cards
Draw/label ATP
Complete the following equation:
ATP _____ + ________ + _______
The process name of adding a phosphate?
What happens to the molecules then?
Name 3 process that need ATP;
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