Photosynthesis

How plants make energy

1. Mesophyll

1. Mesophyll

A layer of cells that contain & are responsible for most of the plant’s photosynthesis

chloroplastschloroplasts

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2. Stomata

Openings in plant leaves that allow for to occur

(CO2) passes in and (O2) passes out.

COCO22

OO22

gas exchange

Carbon Dioxide Oxygen

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Mesophyll Cell

Chloroplast

The site of Photosynthesis

Double-membrane bound organelle

Inner membrane

Outer membrane

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6. Stroma7. Thylakoid

8. Grana

8. Grana

resides in these membranes

Chlorophyll

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Bond Energy and Energy Storing Compounds

ATP, NADPH, FADH2, NADH

How is energy stored in organic compounds?

• When bonds are made by dehydration synthesis, energy is stored within the bonds of the compounds.

How is energy released?

• When bonds are broken by hydrolysis, energy is released from the bonds.

What are some examples of common energy storing

compounds? 1. ATP (Most important usable energy for

the cell.)

2. NADPH

3. FADH2

4. NADH

How is ATP made?

• ATP is made from the precursor AMP (Adenosine Mono-phosphate)

• If a phophate and energy is added to AMP, ADP is created.

• Furthermore, if another phosphate is added to ADP, ATP is created.

How ATP is Made

• AMP

• ADP

• ATP

A

A

A

P P

P P P

P

Equation for ATP synthesis

• ADP + P + energy ATP

How are NADPH, FADH2, and NADH made?

• NADP+ + H+ + electrons NADPH

• FAD+ + H+ + electrons FADH2

• NAD+ + H+ + electrons NADH

• Notice that high energy electrons and hydrogen ions are needed to create NADPH, FADH2 and NADH.

Draw and label the parts of the chloroplast

Photosynthesis (definition)

• The making of food in the form of _______________ (such as glucose) by autotrophic organisms by using sunlight, ____________ gas, and _________________.

What are the two main steps of photosynthesis?

1. ________________

2. ________________ Cycle

• In addition to the wave-like nature of light, light consists of discrete particles called

.

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The Nature of Light

photons

What happens in the light reaction?

• Green ______________ pigment embedded in the ________________________ captures the light energy ____________ from the sun.

• ____________(e-) are taken from __________, and are excited to a higher energy state by the light captured by the chlorophyll pigment.

What happens in the light reaction?

• A complex series of enzymatic reactions occur, and ____ molecules of oxygen gas (O2) are created as a waste product.

• Meanwhile, the energy from the excited electrons is used to create the compounds, __ __ __ and __ __ __ __ __.

• Both ATP and NADPH are high energy compounds used to fuel the ____________ Cycle.

Summary of the Light Reaction

+ ++ +

+ +

ATPATP

+++

+

++

++

+

+

+

++

+

+

+

+

+

+

++

2e-4e-

NADPHNADPH

What happens in the Calvin Cycle?

• The energy from the ATP and NADPH is released when their ___________ are broken.

• The energy released from ATP and NADPH starts another series of enzymatic reactions in the ______________, where __CO2 gas is captured and converted into monosaccharides such as glucose (_____________).

• Glucose serves as “food” or _________ energy for the plant.

PGAL

What is the overall chemical equation for photosynthesis?

• __H2O + __CO2 + sunlight C6H12O6 + __O2

• (water) (carbon dioxide gas) (glucose) + (oxygen gas)

• LR CC CC LR

• LR =

• CC =

Pathway of Photosynthesis

On your own, balance this equation:

CO2 + H2O + (Light) C6H12O6 + O2

Reactants must equal Products

1166 6666

Carbon

Hydrogen

Oxygen

Carbon

Hydrogen

Oxygen

66

1212

66

1212

1818 1818

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