Photosynthesis and Energy Needs of Life

Slide1Regents Biology2006-2007

Slide2Regents Biology2006-2007 Photosynthesis: Life   from   Light  and   Air

Slide3Regents BiologyEnergy needs of life  All life needs a constant input of energy  Animals = Heterotrophs  get their energy from  “ eating others ”  eat food = other organisms =  organic molecules  make energy through  respiration  Plants = Autotrophs  get their energy from  “ self ”  get their energy from sunlight  build organic molecules (food) from CO 2  make energy through  photosynthesis

Slide4Regents Biology

Slide5Regents BiologyPhotosynthesis This is the equation you are used to seeing, but this is not the whole story… +  water  +  energy    glucose  +  oxygen carbon dioxide 6CO 2 6H 2 O C 6 H 12 O 6 6O 2 light energy   + + +

Slide6Regents BiologyHow do  plants  live?  Photosynthesis  Energy building reactions  collect  sun  energy  make ATP  Sugar building reactions  use ATP for energy  use CO 2  as carbon for new sugars  build sugars  glucose, cellulose, starch  build all other organic molecules  proteins, lipids, carbohydrates, DNA  store energy for future use  starch in seeds & roots

Slide7Regents BiologyPhotosynthesis  Actually 2 separate reactions  Energy building  use sunlight  make energy (ATP)  Sugar building  use ATP  use CO 2  make sugars (C 6 H 12 O 6 ) Energy building reactions Sugar building reactions sun ATP ADP CO 2 sugar

Slide8Regents BiologyCO 2 Chloroplasts Chloroplasts Leaf Leaf Chloroplast absorb sunlight & CO 2 make energy & sugar Chloroplasts contain Chlorophyll

Slide9Regents Biology

Slide10Regents BiologyEnergy Building Reactions O 2 H 2 O Energy Building Reactions sunlight ATP H 2 O ATP O 2 light energy  + +  makes ATP energy  releases oxygen as a waste product

Slide11Regents Biology

Slide12Regents BiologySugar Building Reactions sugars C 6 H 12 O 6 CO 2 Sugar Building Reactions ATP CO 2 C 6 H 12 O 6 ADP ATP  + + ADP  builds sugars  uses ATP  cycles ADP back to make more ATP

Slide13Regents BiologyPutting it all together sugars C 6 H 12 O 6 CO 2 ATP ADP H 2 O O 2 sunlight CO 2 H 2 O C 6 H 12 O 6 O 2 light energy  + + + Sugar Building Reactions Energy Building Reactions Plants make both:  ATP  sugars

Slide14Regents Biology Bring In  CO 2  H 2 O  light  Let Out  O 2  Move Around  sugars So what does a plant need? 6CO 2 6H 2 O C 6 H 12 O 6 6O 2 light energy  + + + roots shoot leaves

Slide15Regents Biology

Slide16Regents BiologyLeaf Structure H 2 O CO 2 CO 2 O 2 H 2 O phloem (sugar) xylem (water) stomate guard cell palisades layer spongy layer cuticle epidermis  gases in & out  water out  transpiration O 2

Slide17Regents BiologyStomates  Function of stomates  CO 2  in  O 2  out  H 2 O out guard cell stomate

Slide18Regents Biology

Slide19Regents Biology

Slide20Regents BiologyXylem carry water up from roots

Slide21Regents BiologyPhloem: food-conducting cells  carry sugars around the plant wherever they are needed  new leaves  fruit  seeds

Slide22Regents BiologyPutting it all together  Making a living…  sunlight  leaves = solar collectors  photosynthesis  gases: CO 2  in & O 2  out  stomates = gases in & out  H 2 O  roots take in water from soil  pulled up by leaf evaporation  nutrients  roots take in from soil

Slide23Regents Biology

Slide24Regents BiologyHow are they connected? glucose  +  oxygen    carbon  +  water  +  energy dioxide C 6 H 12 O 6 6O 2 6CO 2 6H 2 O ATP  + + + Respiration +  water  +  energy    glucose  +  oxygen carbon dioxide 6CO 2 6H 2 O C 6 H 12 O 6 6O 2 light energy  + + + Photosynthesis

Slide25Regents Biology

Slide26Regents BiologyH 2 O Energy cycle Photosynthesis Cellular Respiration sun The Great Circle of Life! Where ’ s Mufasa? glucose O 2 CO 2 plants animals ,  plants ATP

Slide27Regents Biology

Slide28Regents BiologyThe poetic perspective  All of the solid material of every  plant was built out of thin air  All of the solid material of every  animal was built from plant material Then all the cats, dogs, mice, people & elephants… are really strands of air woven together by sunlight! sun air