Photosynthesis and the Calvin Cycle

Key:

• Bold: Vocabulary;
• Underline: Knowledge Check;
• Italics: Important Knowledge or Fact Section
• Strikethrough: Notes that require extra knowledge

Background Knowledge: Atoms enter into these chemical reactions to satisfy the octet rule and to make energy for the plant.

Thylakoid: are green, stacked like structures inside of a chloroplast cell of a plant; also has a phospholipid bilayer that contains photosystems where the reactions take place.

Intermembrane space is space between the inner and outer membranes

The stroma is the space surrounding the Thylakoid.

2 stages in photosynthesis.

First Stage

Light energy from the sun is absorbed by the Thylakoids ( chlorophylls inside them) and water (H2O) is converted to oxygen O2. The electron from the two separate Hydrogen molecules is used in photosynthesis.

Calvin cycle occurs in Stroma. Energy Shuttle and electron shuttle are created, both shuttles go over to the calvin cycle.

ATP - energy (adenosine triphosphate)

NATDPH - carries electrons (nicotinamide adenine dinucleotide phosphate)

photosystems - proteins embedded in thylakoid membrane. chlorophyll location.

(Ground state to excited state when electrons absorb sunlight) (gain energy). Electron is then passed through the electron transport chain.

Which are more protein electrons in the membrane, each protein it passed through energy is released to create ATP

NADP+ takes another highly charged electron to make NADPH.

Second Phase: Calvin Cycle in the Stroma

Reactants: NADPH and ATP, CO2 (from air via stomata)

---->1 carbon atom is removed from the CO2 and added to 3 5-carbon molecules to make 3 6-cabon molecules

---->3 6-carbon molecules break up into 6 3-carbon molecules 3-PGA

---->ADP and NADPH is used to create G3P

----> some G3P is used but the rest is converted back to RuBP which is the 3 5-carbon molecules.

Product: Sugar C6H12O6, G3P to make glucose;

Note: Sugar is stored in the bonds of a sugar molecule during the process of photosynthesis

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Write full equation for Photosynthesis:

6CO2 + 6H2O --> C6H12O6 + 6O2

Explain steps in light-dependent reactions:

1. H2O is converted into 2 Hydrogen atoms to use their electrons

2. Light is absorbed by the chlorophylls and the electron goes from a ground state to an excited state.

Explain steps in Calvin Cycle:

1. 3 5-Carbon RuBP molecules take 1 carbon each from CO2 molecules and become 3 6-carbon molecules.

2.Energy is used to break those 3 6-carbon into 6 3carbon molecules called 3-PGA.

3. 3-PGA is then acted upon by ATP and NADPH to make G3P which is then converted to glucose for use or returned to a 3 5-carbon RuBP molecule to start the process again.

Where do light-dependent and Calvin cycle reactions occur:

Light dependent reactions occur in the thylakoid, more specifically the photosystem. Calvin Cycle takes place in the stroma.

what the are the reactants and products?

Light dependent reactants include H2O Products include: ATP and NADPH.

Calvin Cycle reactants include: CO2, ATP,NADPH and products include C6H12O6 and O2

explain the roles of light, h2o, photosystems, chlorophyll, electron transport chain, NADP+, NAPFH, ADP/ATP

Light is used as energy. H2O is used to receive its electron by breaking it down. photosystems are the proteins in the thylakoid membrane where this takes place. chlorophylls collect light energy. the electron transport chain help in create ATP by releasing energy every time the electron is passed through a protein. NADP+ is used as a carrier for a highly charged electron. ADP is used as energy. NADPH is the electron carrier and ATP is the final form of that energy.

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Course: human biology 1050

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