Chapter 6 & 7 Chapter 6 & 7 Photosynthesis and Photosynthesis and RespirationRespiration

I. ENERGY: The ability to do I. ENERGY: The ability to do workwork

A. Why do cells need energy?A. Why do cells need energy?1) Active Transport1) Active Transport2) Cell division, growth and 2) Cell division, growth and

developmentdevelopment3) To make macromolecules- 3) To make macromolecules-

proteins, carbohydrates, etc.proteins, carbohydrates, etc.4) To build cell parts-extra cellular 4) To build cell parts-extra cellular

membranes membranes

B. Two classifications of organisms based B. Two classifications of organisms based

upon how they obtain energy:upon how they obtain energy:

1) Autotrophs: (producers) organisms 1) Autotrophs: (producers) organisms that can make their own food( glucose); that can make their own food( glucose); example plantsexample plants

AutotrophsAutotrophs

2) Heterotrophs: (consumers) organisms 2) Heterotrophs: (consumers) organisms that obtain food from other sources; that obtain food from other sources; example: animals and fungiexample: animals and fungi

HeterotrophsHeterotrophs

C. Pathway of Energy: C. Pathway of Energy:

photosynthesis photosynthesis cellular respirationcellular respiration

SunSun autotrophs autotrophs food(glucose) food(glucose) heterotrophs heterotrophs ATP ATP

D. Cellular Energy = ATP: Adenosine D. Cellular Energy = ATP: Adenosine TriphosphateTriphosphate

Removes phosphate Removes phosphateRemoves phosphate Removes phosphate

Release energy Release energyRelease energy Release energy

ATP is like a rechargeable batteryATP is like a rechargeable battery

ATP ADP AMP

Overview of photosynthesis and Overview of photosynthesis and respirationrespiration

PHOTOSYNTHESISPHOTOSYNTHESIS CELLCELLACTIVITIESACTIVITIES

RESPIRATIONRESPIRATION

SUNSUN

RADIANT RADIANT ENERGYENERGY

GLUCOSEGLUCOSE ATP(ENERGY)ATP(ENERGY)

E. Photosynthesis: 2 E. Photosynthesis: 2 RXNSRXNS

Light-Dependent Light-Dependent ReactionsReactions

Light-Independent Light-Independent ReactionsReactions

II. PHOTOSYNTHESIS: II. PHOTOSYNTHESIS: PHOTO = light SYNTHESIS = to makePHOTO = light SYNTHESIS = to make

Process by which solar energy is converted to Process by which solar energy is converted to cellular energy (ATP) and stored food (glucose)cellular energy (ATP) and stored food (glucose)

Overall Reaction: Overall Reaction: sunlightsunlight

6 CO6 CO22 + 6 H + 6 H220 0 C C66HH1212OO6 6 + 6 O + 6 O22

chlorophyllchlorophyll

Occurs in the chloroplasts of plant cellsOccurs in the chloroplasts of plant cells Solar E is converted by the use of pigment, Solar E is converted by the use of pigment,

molecules that absorb certain wavelengths of molecules that absorb certain wavelengths of light and reflect (what we see) others.light and reflect (what we see) others.

Chlorophyll: main photosynthetic Chlorophyll: main photosynthetic pigment, absorbs red & blue light, reflects pigment, absorbs red & blue light, reflects greengreen

Accessory pigments: Accessory pigments: Carotenes: absorb blue & green, reflect Carotenes: absorb blue & green, reflect

yellow and orange.yellow and orange. In fall, chlorophyll is broken down so we In fall, chlorophyll is broken down so we

see the colors of the accessory pigments. see the colors of the accessory pigments.

Photosynthesis consists of two Photosynthesis consists of two phases:phases:

1) Light Reactions: the “photo” part1) Light Reactions: the “photo” part Solar energy converted to cellular energy Solar energy converted to cellular energy

(ATP)(ATP) Chlorophyll “captures” (absorbs) lightChlorophyll “captures” (absorbs) light Water is split, releasing oxygen gasWater is split, releasing oxygen gas Occurs in the thylakoid membranes of Occurs in the thylakoid membranes of

the chloroplast the chloroplast

2) Calvin Cycle: the “synthesis” part2) Calvin Cycle: the “synthesis” part Energy from light reactions used to “fix” Energy from light reactions used to “fix”

COCO22 into glucose (C into glucose (C66HH1212OO66))

Occurs in the stroma of the chloroplast.Occurs in the stroma of the chloroplast. Called Dark or light independent Called Dark or light independent

ReactionsReactions

In hot dry conditions plants loose water In hot dry conditions plants loose water through through stomatastomata which are small pores which are small pores usually located on the undersurface of usually located on the undersurface of leavesleaves

They close these to prevent water lossThey close these to prevent water loss

The rate of photosynthesis is affected The rate of photosynthesis is affected by:by:Light intensity, carbon dioxide levels, Light intensity, carbon dioxide levels, temperaturetemperature

E. Photosynthesis: 2 E. Photosynthesis: 2 RXNSRXNS

Light-Dependent Light-Dependent ReactionsReactions

Light-Independent Light-Independent ReactionsReactions

Link between Link between photosynthesis and photosynthesis and respirationrespiration

EQUATIONEQUATION FORFOR PHOTOSYNTHESISPHOTOSYNTHESIS

6CO6CO22 + + 6H6H22OO + +ENERGYENERGY CC66HH1212OO66 + + 6O6O22

CARBON CARBON DIOXIDEDIOXIDE

WATERWATER

GLUCOSEGLUCOSE

OXYGENOXYGEN

EQUATION FOREQUATION FOR RESPIRATIONRESPIRATION

CC66HH1212OO66 + +GLUCOSEGLUCOSE

6O6O22

OXYGENOXYGEN

6CO6CO22 ++

CARBON CARBON DIOXIDEDIOXIDE

6H6H22OO + +ENERGYENERGY

WATERWATER

ATPATP

III. CELLULAR RESPIRATIONIII. CELLULAR RESPIRATION

A series of chemical reactions that release A series of chemical reactions that release energy by breaking down glucose and making energy by breaking down glucose and making HH22O and COO and CO22..

Overall Reaction:Overall Reaction: CC66HH1212OO6 6 + 6 O + 6 O2 2 6 CO 6 CO22 + 6 H + 6 H220 0 Glucose is the primary source of energy at the Glucose is the primary source of energy at the

cellular level. The stored energy in its bonds cellular level. The stored energy in its bonds will be converted to cellular energy in the form will be converted to cellular energy in the form of ATP. of ATP.

Cellular respirationCellular respiration

Occurs in the mitochondriaOccurs in the mitochondria

GLUCOSE ATP

PATHWAYS OF GLYCOLYSIS PATHWAYS OF GLYCOLYSIS & RESPIRATION& RESPIRATION

DiagramDiagram