Overview of Photosynthesis

B-3.1Summarize the overall process by which photosynthesis converts solar energy into chemical energy and interpret the chemical equation for the process.

Overview of Photosynthesis

KEY CONCEPTThe overall process of photosynthesis produces sugars that store chemical energy.

Overview of Photosynthesis

Photosynthetic organisms are producers.

• Producers make their own source of chemical energy.

• Plants use photosynthesis and are producers.

• Photosynthesis captures energy from sunlight to make sugars.

Overview of Photosynthesis

• Chlorophyll is a molecule that absorbs light energy.

chloroplast

leaf cell

leaf

• In plants, chlorophyll is found in organelles called chloroplasts.

Overview of Photosynthesis

Photosynthesis in plants occurs in chloroplasts.

• Photosynthesis takes place in two parts of chloroplasts.– grana (thylakoids)– stroma

chloroplast

stroma

grana (thylakoids)

Overview of Photosynthesis

• The light-dependent reactions capture energy from sunlight.

– take place in thylakoids– water and sunlight are needed– chlorophyll absorbs energy– two energy storing molecules (ATP and NADPH) are

produced. – The solar energy is

used to split water

molecules which results

in the release of oxygen

as a waste product.

Overview of Photosynthesis

• The light-dependent reactions produce ATP.

– hydrogen ions flow through a channel in the thylakoid membrane

– ATP synthase attached to the channel makes ATP

Overview of Photosynthesis

Overview of Photosynthesis

• The light-independent reactions make sugars.

– take place in stroma– needs carbon dioxide from atmosphere– use energy to build a sugar in a cycle of chemical

reactions

Overview of Photosynthesis

Overview of Photosynthesis

• The equation for the overall process is:

6CO2 + 6H2O C6H12O6 + 6O2

C6H12O6

granum (stack of thylakoids)

thylakoid

sunlight

1 six-carbon sugar

6H2O

6CO2

6O2

chloroplastchloroplast1

2

43

energy

stroma (fluid outside the thylakoids)

Overview of Photosynthesis

Photosynthesis Quiz on Monday!!•Not open note!!•You must memorize the equation for photosynthesis.•Also includes 7 multiple choice questions.

Overview of Photosynthesis

CWComplete 4.1 in the Study Guide

HWComplete 4.2 in the Study Guide.