Text of Energy in the cell photosynthesis - cellular respiration
1.Energy in a Cell
Cells need energy to do a variety of work:
Making new molecules.
Building membranes and organelles.
Moving molecules in and out of the cell.
Food is broken down to a form the cell can use.
Extra energy is stored in an ATP molecule, a nucleotide.
ATP adenosine triphosphate is a molecule made up of an adenine, ribose, and 3 phosphate groups.
Adenine Ribose phosphate groups 5.
Energy is stored in the bond between the second and third phosphate group.
When the bond is broken, energy is released and ADP is formed.
Adenine Ribose 6.
Within a cell, formation of ATP from ADP and phosphate occurs over and over, storing energy each time.
As the cell uses energy, ATP breaks down repeatedly to release energy and form ADP and phosphate.
Cells make energy in two ways:
Photosynthesis takes place in the chloroplasts.
Respiration takes place in the mitochondria.
Autotrophs make their own food by trapping light energy and converting it to chemical energy (carbohydrates).
Using light from the sun, plants combine water and carbon dioxide to make sugar .
6CO 2+ 6H 2 O + energyC 6 H 12 O 6+ 6O 2
Light Reactions Light energy is converted to chemical energy to split hydrogen from water.
Takes place in the grana of the chloroplasts (the coin-like stacks of sacs).
Byproducts are oxygen, NADPH, and ATP.
Calvin Cycle ATP and NADPH from the light reactions are used along with CO 2to form a simple sugar (glucose).
Takes place in the stroma of the chloroplasts (the liquid filling).
Byproducts are C 6 H 12 O 6(glucose), ADP, and NADP +(which return to the light reactions).
13. Sunlight NADP + ADP NADPH CO 2 H 2 O O 2 CHLOROPLAST Calvin cycle ATP Glucose Photosystem I & II 14.
Some autotrophs can convert inorganic substances to energy.
Most are adapted to live in conditions where there is no oxygen.
Digestive tracts of mammals.
Deep in the ocean.
The process of breaking down food molecules to release energy.
Occurs in the mitochondria.
Aerobic requires oxygen.
Anaerobic requires an absence of oxygen.
Two types of anaerobic respiration:
Fermentation occurs when bacteria break down plants (vegetables and fruit) and release alcohol or vinegar.
Lactic Acid Fermentation occurs in muscles a buildup of lactic acid causes soreness.
Krebs Cycle (or Citric Acid Cycle)
Electron Transport Chain
Glycolysis glucose is split to form pyruvate.
Takes place in the cytoplasm of the cell.
ATP is a byproduct.
Krebs Cycle pyruvate is used to build citric acid (a carbon compound), which is broken down to release ATP.
Takes place in the cristae (the folded membrane in the mitochondrion).
CO 2is released, and NADH carries hydrogen ions to the electron transport chain.
Electron Transport Chain hydrogen ions are stripped of their energy, and large amounts of ATP are formed.
Takes place in the inner membrane of the mitochondrion.
The used ions are combined with oxygen to form H 2 O.
22. MITOCHONDRION CO 2 H 2 O O 2 ATP NADH Heat Electron Transport System ATP NAD + citric acid cycle Pyruvate Glucose ATP 23. Sunlight Photo- System I Photo- system II NADP + ADP NADPH ATP Calvin CO 2 H 2 O O 2 ATP ATP NAD + NADH Electron Transport System Cycle Krebs Heat CHLOROPLAST MITOCHONDRION Glucose Pyruvate Cycle ATP Glycolysis 24. Sunlight Photo- System I Photo- system II NADP + ADP NADPH ATP Cycle Calvin CO 2 H 2 O O 2 ATP ATP NAD + NADH Electron Transport System Cycle Krebs Heat CHLOROPLAST MITOCHONDRION Glucose ATP Pyruvate Glycolysis