chloroplast CHAPTER 8 Photosynthesis leaf cell leaf Key

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chloroplast CHAPTER 8 Photosynthesis: leaf cell leaf

chloroplast CHAPTER 8 Photosynthesis: leaf cell leaf

Key Concept Questions: § Where do plants get the energy they need to §

Key Concept Questions: § Where do plants get the energy they need to § § produce food? What is the role of ATP in cellular activities? What is the overall equation for photosynthesis? What is the role of light and chlorophyll in photosynthesis? What is the function of stomates and guard cells?

§ http: //www. pearsonsuccessnet. com/sn § papp/learn/navigate. IDP. do? method=sc o. Viewer&internal. Id=301310100000498 http:

§ http: //www. pearsonsuccessnet. com/sn § papp/learn/navigate. IDP. do? method=sc o. Viewer&internal. Id=301310100000498 http: //www. pearsonsuccessnet. com/sn papp/learn/navigate. IDP. do? method=sc o. Viewer&internal. Id=301310100000499

Energy needs of life § All life needs a constant input of energy u

Energy needs of life § All life needs a constant input of energy u Animals = Heterotrophs § get their energy from “eating others” weat food = other organisms = organic molecules § make energy through respiration

u Plants = Autotrophs § get their energy from “self” wget their energy from

u Plants = Autotrophs § get their energy from “self” wget their energy from sunlight wbuild organic molecules (food) from CO 2 § make energy through photosynthesis

Photosynthesis carbon + water + energy glucose + oxygen dioxide 6 CO 2 +

Photosynthesis carbon + water + energy glucose + oxygen dioxide 6 CO 2 + 6 H 2 O + light �C 6 H 12 O 6 + 6 O 2 energy This is the equation you should get used to seeing, but this is not the whole story…

What is the main chemical fuel that most living organisms use to store energy?

What is the main chemical fuel that most living organisms use to store energy? § ATP – adenosine triphosphate P T A What does an ATP molecule consist of? Adenine, ribose, and three phosphate groups What do the lines between the parts of the molecule represent? Chemical bonds

WHAT IS THE ROLE OF ATP IN CELLULAR ACTIVITIES? § The characteristics of ATP

WHAT IS THE ROLE OF ATP IN CELLULAR ACTIVITIES? § The characteristics of ATP make it an exceptionally useful molecule that is used by all types of cells as their basic energy source

§ Even though ATP is very efficient at § § transferring energy, it is

§ Even though ATP is very efficient at § § transferring energy, it is not very good for storing energy over the long term. Living organisms store large amounts of energy in the form of glucose (90 times more energy than ATP) Cells can break apart glucose and make ATP molecules very easily to release the energy slowly

How do plants live? § Photosynthesis u Energy building reactions § collect sun energy

How do plants live? § Photosynthesis u Energy building reactions § collect sun energy § use CO 2 as carbon for new sugars w glucose, cellulose, starch § build all other organic molecules w proteins, lipids, carbohydrates, DNA § store energy for future use or to be eaten w starch in seeds & roots

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

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

Putting it all together CO 2 + H 2 O + light C 6

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

WHAT IS THE ROLE OF CHLOROPHYLL IN PHOTOSYNTHESIS? § In addition to water and

WHAT IS THE ROLE OF CHLOROPHYLL IN PHOTOSYNTHESIS? § In addition to water and carbon dioxide, § photosynthesis requires light and chlorophyll, a molecule in chloroplasts Sunlight, which your eyes perceive as “white” light, is actually a mixture of different wavelengths of light of various colors

Any compound that absorbs light also absorbs energy from that light. When chlorophyll absorbs

Any compound that absorbs light also absorbs energy from that light. When chlorophyll absorbs light, much of the energy is transferred directly to electrons in the chlorophyll molecule, raising the energy levels of these electrons. These highenergy electrons make photosynthesis work HOW WELL WOULD A PLANT GROW UNDER PURE YELLOW LIGHT? The plant would not grow well because neither chlorophyll a nor b absorbs much light in the yellow region of visible light

Factors that can affect photosynthesis § water § temperature § intensity of light

Factors that can affect photosynthesis § water § temperature § intensity of light

So what does a plant need? § Bring In leaves CO 2 u H

So what does a plant need? § Bring In leaves CO 2 u H 2 O u light u shoot § Let Out u O 2 § Move Around u roots sugars 6 CO 2 + 6 H 2 O + light C 6 H 12 O 6 + 6 O 2 energy

Leaf Structure cuticle epidermis xylem (water) phloem (sugar) palisades layer spongy layer O 2

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

Stomates § Function of stomates u u CO 2 in O 2 out guard

Stomates § Function of stomates u u CO 2 in O 2 out guard H 2 O out Prevents dehydration cell stomate

Xylem carry water up from roots

Xylem carry water up from roots

Phloem: food-conducting cells § carry sugars around the plant wherever they are needed t

Phloem: food-conducting cells § carry sugars around the plant wherever they are needed t new leaves t fruit t seeds

Putting it all together § Making a living… u sunlight § leaves = solar

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

How are they connected? Respiration glucose + oxygen carbon + water + energy dioxide

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

Energy cycle sun Photosynthesis plants CO 2 glucose H 2 O animals, plants Cellular

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

Key Concept Questions: § Where do plants get the energy they need to produce

Key Concept Questions: § Where do plants get the energy they need to produce food? u Sunlight § What is the role of ATP in cellular activities? u It is used by all types of cells as their basic energy source § What is the overall equation for photosynthesis? 6 CO 2 + 6 H 2 O + light �C 6 H 12 O 6 + 6 O 2 energy

Key Concept Questions: § What is the role of light and chlorophyll in photosynthesis?

Key Concept Questions: § What is the role of light and chlorophyll in photosynthesis? u Chlorophyll absorbs light and this energy is used to drive photosynthesis § What is the function of stomates and guard cells? Guard cells control the size of the stomate. u Stomates allow CO 2 to enter the leaf and H 2 O and O 2 to leave the leaf u