The BasicsThe Basics

PhotosynthesPhotosynthesis is

and and Cell Cell

RespirationRespiration

Sunlight Powers LifeSunlight Powers Life

• Certain organisms convert Certain organisms convert energy energy from sunfrom sun to to chemical energy in foodchemical energy in food……– Some make food themselvesSome make food themselves

• AUTOtrophsAUTOtrophs producers (photosynthesis) producers (photosynthesis)

– Some rely on others for foodSome rely on others for food• HETEROtrophsHETEROtrophs consumers consumers

ALWAYS starts with the sunALWAYS starts with the sun

Regardless of Regardless of PhotosynthesisPhotosynthesis or or RespirationRespiration

Working TogetherWorking Together• The productsproducts of

photosynthesis are the chemical ingredientsingredients for cellular respiration

• The productsproducts of cellular respiration are the chemical ingredientsingredients for photosynthesis

ATP is ENERGY!ATP is ENERGY!• Adenosine Tri Phosphate

ATP = Adenosine Tri-Phosphate-Energy needed for cellular work

• ATP ADP + P + energy • Energy released used in metabolic activity

P PP

DiDi

ENERGY

ATP CycleATP Cycle• ATP continuously converted to ATP continuously converted to

ADP as cells do work… ADP as cells do work… but cant but cant useuse ADP… ADP…

• Recycles!Recycles! • Page 144

PhotosynthesisPhotosynthesisDirect from the sunDirect from the sun

The stages of PhotosynthesisThe stages of PhotosynthesisThe Light Dependent The Light Dependent

ReactionReaction• 3 stages

Stage 1: Energy is Stage 1: Energy is captured from sunlightcaptured from sunlight• Done by leaves

– Contain chloroplasts, chlorophyllchlorophyll (green pigment)

» Absorbs blue and red, reflects yellow and green

• Stage 2Stage 2Light energy converted into Light energy converted into

chemical energychemical energy• Stored in ATP and NADPH (e- carrier)

Light NRG

ADP

ATP

NADP+

NADPH

Chemical NRG

The stages of The stages of PhotosynthesisPhotosynthesis

The Light Dependent The Light Dependent ReactionReaction

Stages of Stages of Photosynthesis: Photosynthesis:

Light Independent ReactionLight Independent Reaction–Step 3

• NRG stored in ATP and NADPH powers formation of organic compounds (sugars) by using CO2

End products of End products of photosynthesis ARE:photosynthesis ARE:

Sugar (organic compound) and Oxygen

ATPOxygen

Light Reaction and Calvin Cycle

Reflection Reflection ActivityActivity

why plants grown in shaded areas produce

larger leaves than those grown in direct sunlight?

Why Do Leaves Turn Autumn Colors?

• Tree and plant leaves contain pigments that give them their color.color.

Three pigments are involved in fall color:· • Chlorophyll (a & b)Chlorophyll (a & b) — gives leaves their green color. • CarotenoidsCarotenoids —yellow, orange, brown colors• AnthocyaninsAnthocyanins — give the red and purple colors.

During the growing season, most tree leaves are green because they are full of chlorophyll.

Leaves turn different colors in the fall because chlorophyll a & b are not being made!

As these pigments dissipate out of the leaves the accessory pigments (other colors)accessory pigments (other colors) become

visible.visible.

So…Why do leaves changechange colors in the fallfall?

Leaves turn different colors in the fall because chlorophyll a & b are not being made!

As these pigments dissipate out of the leaves the accessory pigments (other accessory pigments (other colors)colors) become visible.visible.

Photosynthesis Photosynthesis ReviewReview

1. Is it direct or indirect?

2. What is “Stage 1”a) Where is this happening?

b) What pigment absorbs the light energy?

3. What is “Stage 2”a) What is the name of the chemical energy?

b) What is “carrying” the electrons?

4. What is “Stage 3”a) What 2 things power the formation of sugar?

b) What is the name of the final sugar made?

c) What else is made at the end besides sugar?