Chapter 4: Cells and Energy pt. 1
All cells need chemical energy
ATP: A molecule that transfers energy so that cells can use it.
ATP uses energy from the breakdown of molecules.
ADP: Molecule that can be converted into ATP by adding a phosphate group.
Foods must be broken down into carbon-based molecules in order to create ATP for energy.
The type of food can affect how much ATP is produced.
Organisms like plants rely on sunlight to produce energy through photosynthesis
Organisms like animals rely on sunlight indirectly through eating plants.
Certain organisms do not require sunlight and find other energy sources.
Chemosynthesis: The process by which some organisms use chemical energy instead of light energy to make carbon-based molecules.
Chemosynthetic organisms make their own food like plants.
The overall process of photosynthesis produces sugars that store chemical energy
Producers are organisms that create a source of chemical energy for themselves and other organisms.
Plants are producers because the energy they create through photosynthesis is used when other organisms consume the plants.
Photosynthesis: A process that captures energy from sunlight to make sugars that store chemical energy.
The food chain usually begins with sunlight being the direct energy source for plants.
Plants absorb visible light for photosynthesis.
Chlorophyll: A molecule that absorbs energy in visible light.
Found in chloroplasts, an organelle in plant cells.
Chloroplasts need the grana and the stroma for photosynthesis.
Grana are stacks of thylakoids.
Thylakoids: Compartments in chloroplasts that contain chlorophyll and light-absorbing proteins.
The stroma is the fluid outside the thylakoids.
Light-dependent reactions: Reactions that capture energy from sunlight in or near the thylakoids.
Water and sunlight are needed for this.
Light-independent reactions: Reactions that use energy from the light-dependent reactions to make sugars.
Occur in the stroma of chloroplasts.
CO2 is needed for this.
Sugars that are formed from these reactions store the light energy that was captured.
Photosynthesis equation:
6CO2 + 6H2O → C6H12O6 + 6O2
Photosynthesis requires a series of chemical reactions.
Photosystems: Molecules that transfer captured energy.
Used during light-dependent reactions.
During light-dependent reactions, energy is captured and transferred to electrons.
Energy from electrons is used to make energy carriers (ATP and NADPH)
In photosystem II energy is absorbed from sunlight.
The energy is transferred to electrons.
Electron transport chain: Transports electrons after they leave the chlorophyll.
Electrons from broken down water molecules replace the electrons that left the chlorophyll.
Within the chain, the electrons’ energy is used to push hydrogen ions into the thylakoid.
In photosystem I , energy is absorbed from sunlight as well.
The energy is added to electrons which may be from photosystem II.
NADPH is produced with the new energy from the electrons
NADPH can be used to transfer energy for light-independent reactions.
ATP is produced with the hydrogen ions building in the thylakoid with the electrons’ help.
ATP synthase: An enzyme that completes the production of ATP
ATP synthase adds phosphate groups to ADP to make ATP.
Energy is captured from sunlight and produced into oxygen, NADPH, and ATP.
Energy from ATP and NADPH can be used to make sugars.
Light-independent reactions do not need sunlight but need energy from ATP and NADPH.
Calvin Cycle: Cycle that uses carbon dioxide and energy from ATP and NADPH to make simple sugars.
When carbon dioxide is added to the cycle, carbon molecules are formed and bonded into sugars.
Energy from ATP and NADPH and carbon dioxide enter the Calvin cycle.
Sugars are formed from carbon molecules and leftover products are recycled to be used again.
Photosynthesis is important for plants’ growth and development, for regulating the environment with oxygen, and for producing food for other organisms.
All cells need chemical energy
ATP: A molecule that transfers energy so that cells can use it.
ATP uses energy from the breakdown of molecules.
ADP: Molecule that can be converted into ATP by adding a phosphate group.
Foods must be broken down into carbon-based molecules in order to create ATP for energy.
The type of food can affect how much ATP is produced.
Organisms like plants rely on sunlight to produce energy through photosynthesis
Organisms like animals rely on sunlight indirectly through eating plants.
Certain organisms do not require sunlight and find other energy sources.
Chemosynthesis: The process by which some organisms use chemical energy instead of light energy to make carbon-based molecules.
Chemosynthetic organisms make their own food like plants.
The overall process of photosynthesis produces sugars that store chemical energy
Producers are organisms that create a source of chemical energy for themselves and other organisms.
Plants are producers because the energy they create through photosynthesis is used when other organisms consume the plants.
Photosynthesis: A process that captures energy from sunlight to make sugars that store chemical energy.
The food chain usually begins with sunlight being the direct energy source for plants.
Plants absorb visible light for photosynthesis.
Chlorophyll: A molecule that absorbs energy in visible light.
Found in chloroplasts, an organelle in plant cells.
Chloroplasts need the grana and the stroma for photosynthesis.
Grana are stacks of thylakoids.
Thylakoids: Compartments in chloroplasts that contain chlorophyll and light-absorbing proteins.
The stroma is the fluid outside the thylakoids.
Light-dependent reactions: Reactions that capture energy from sunlight in or near the thylakoids.
Water and sunlight are needed for this.
Light-independent reactions: Reactions that use energy from the light-dependent reactions to make sugars.
Occur in the stroma of chloroplasts.
CO2 is needed for this.
Sugars that are formed from these reactions store the light energy that was captured.
Photosynthesis equation:
6CO2 + 6H2O → C6H12O6 + 6O2
Photosynthesis requires a series of chemical reactions.
Photosystems: Molecules that transfer captured energy.
Used during light-dependent reactions.
During light-dependent reactions, energy is captured and transferred to electrons.
Energy from electrons is used to make energy carriers (ATP and NADPH)
In photosystem II energy is absorbed from sunlight.
The energy is transferred to electrons.
Electron transport chain: Transports electrons after they leave the chlorophyll.
Electrons from broken down water molecules replace the electrons that left the chlorophyll.
Within the chain, the electrons’ energy is used to push hydrogen ions into the thylakoid.
In photosystem I , energy is absorbed from sunlight as well.
The energy is added to electrons which may be from photosystem II.
NADPH is produced with the new energy from the electrons
NADPH can be used to transfer energy for light-independent reactions.
ATP is produced with the hydrogen ions building in the thylakoid with the electrons’ help.
ATP synthase: An enzyme that completes the production of ATP
ATP synthase adds phosphate groups to ADP to make ATP.
Energy is captured from sunlight and produced into oxygen, NADPH, and ATP.
Energy from ATP and NADPH can be used to make sugars.
Light-independent reactions do not need sunlight but need energy from ATP and NADPH.
Calvin Cycle: Cycle that uses carbon dioxide and energy from ATP and NADPH to make simple sugars.
When carbon dioxide is added to the cycle, carbon molecules are formed and bonded into sugars.
Energy from ATP and NADPH and carbon dioxide enter the Calvin cycle.
Sugars are formed from carbon molecules and leftover products are recycled to be used again.
Photosynthesis is important for plants’ growth and development, for regulating the environment with oxygen, and for producing food for other organisms.
