Tiếng Anh 6 - Unit 1 Part B-1

Capture light energy in the form of a photon with Capture light energy in the form of a photon with chlorophyll pigment4. chlorophyll pigment and excite electron in and excite electro[r]

Chapter Photosynthesis: Seven things to know Chapter Photosynthesis: Seven things to know

1 General chemical equation (7.3-7.4) General chemical equation (7.3-7.4)

2 Part of the plant cell involved (7.2) Part of the plant cell involved (7.2)

3

3 Photosynthesis is composed of processes (7.5)Photosynthesis is composed of processes (7.5)

4 General description of light reaction (7.6-7.9)General description of light reaction (7.6-7.9)

5 General description of Calvin cycle (7.10)General description of Calvin cycle (7.10)

6 Importance of ATP and NADPH (7.11)Importance of ATP and NADPH (7.11)

Common theme in biology: Energy processing

Acquiring energy and transforming it to a form useful for the organism

Energy: the ability to do Work

*Photosynthesis

Photosynthetic Organisms are autotrophs/producers

What plants need to survive? What are the REACTANTS for

I General chemical equation I General chemical equation

Photosynthesis: Sun energy to chemical energy

Photosynthesis: Sun energy to chemical energy

II Parts of plant cell involved II Parts of plant cell involved

 COCO22 enters leaf through stomata enters leaf through stomata

 LightLight is absorbed through the green portions of plants is absorbed through the green portions of plants  leaves leaves

Mesophyll tissueMesophyll tissue

Tissue composed of Tissue composed of cellscells containing containing chloroplastschloroplasts Chloroplasts contain Chloroplasts contain chlorophyllchlorophyll pigment pigment

Place the following terms in the correct order from BIGGEST to SMALLEST

 Thlakoid  Cell

 Chloroplast

III Photosynthesis is composed of processes III Photosynthesis is composed of processes

 Light Reaction: Light Reaction:

Use

Use light energylight energy to split water; make NADPH and to split water; make NADPH and ATP

ATP

 Calvin Cycle Reaction:Calvin Cycle Reaction:

Incorporate light reaction products; change CO

Incorporate light reaction products; change CO22 to to

G

Oxidation-Reduction Oxidation-Reduction

 Oxidation-reduction (redox)Oxidation-reduction (redox) reactions: reactions:

““LEO says GER”LEO says GER”

LLose ose EElectrons = lectrons = OOxidationxidation GGain ain EElectrons = lectrons = RReductioneduction

 Both take place at same timeBoth take place at same time

One molecule accepts the electron given up by the otherOne molecule accepts the electron given up by the other

REDOX Reactions Transfer of electron Na Sodium atom Is oxidized Cl Chlorine atom Is reduced Na+ Sodium ion Cl– Chloride ion

Na Cl Na Cl

+ –

–

–

NADPH

•Nicotinamide Adenine Dinucleotide Phosphate

•Electron Carrier

•Coenzyme

IV General description of light reaction IV General description of light reaction

1

1 Capture light energy in the form of a photon with Capture light energy in the form of a photon with chlorophyll pigment

chlorophyll pigment and excite electron in and excite electron in

photosystem photosystem

2 Water splits to replace lost electronsWater splits to replace lost electrons

3 Transfer electron to electron transport chain (ETC) Transfer electron to electron transport chain (ETC)

4 Creation of H+ concentration gradient Creation of H+ concentration gradient

5

5 NADP+ is reduced to NADPHNADP+ is reduced to NADPH

Light

Chloroplast Thylakoid

Absorbed light

Transmitted light

1.

Chlorophyll molecule

Excited state

Ground state Heat

Photon

Photon

(fluorescence)

+

O2 H2O

1



2 H

+

NADP+ H+ NADPH

+ 2

H+

H+

H+ H+

H+ H+ H+ H+ H+ H+ H+ H+

H+ H+

ATP synthase Light

Light

Stroma (low H+

concentration)

Thylakoid space

(high H+ concentration)

ADP + P ATP

1 Capture light energy

2 Water splits and releases electron

3 Pass electron down ETC

4 Create H+ gradient

5 NADPH produced

6 ATP produced

Is H2O oxidized or reduced?

Is NADP+ oxidized or

V General description of Calvin Cycle (aka Dark V General description of Calvin Cycle (aka Dark

Reaction, Light Independent) Reaction, Light Independent)

1

1 Carbon fixation of COCarbon fixation of CO22 and cycling of various and cycling of various

carbon products carbon products

2 Use of light reaction products (NADPH & ATP)Use of light reaction products (NADPH & ATP)

3 Production of G3P (glyceraldehade-3-phosphate) Production of G3P (glyceraldehade-3-phosphate) to make glucose

The Calvin Cycle: Fixation of CO2

1 CO2 fixation

2 Use of light reaction products

NADPH ATP RuBP 3 P G3P P Input: CO2 1 Rubisco 3 P Step Carbon fixation

3-PGA 6 P CALVIN CYCLE 6 6 6 6 P Step Reduction

2 2 G3P 5 P 3 3 G3P 1 P Glucose and other compounds Output:

Step Release of one molecule of G3P

1

Step Regeneration of RuBP4

4

ATP 3

3 ADP

NADP+

Importance of Calvin Cycle Importance of Calvin Cycle

 G3P (glyceraldehyde-3-phosphate) can be converted G3P (glyceraldehyde-3-phosphate) can be converted

to many other molecules to many other molecules

Glucose phosphate (simple sugar)Glucose phosphate (simple sugar)

Fatty acids and glycerol to make plant oilsFatty acids and glycerol to make plant oils Fructose (which with glucose = sucrose)Fructose (which with glucose = sucrose) Starch and celluloseStarch and cellulose

General chemical equation General chemical equation

6CO

6CO22 + 6H + 6H22OOSolar energySolar energy CC66HH1212OO66 + 6O + 6O2 (+686 kcal/mol)2 (+686 kcal/mol)

Reduced



H2O

NADP+

ADP P LIGHT

REACTIONS (in thylakoids) Light

Chloroplast

H2O

ADP P LIGHT

REACTIONS (in thylakoids) Light

Chloroplast

NADPH ATP

O2



NADP+

VII Alternate pathways VII Alternate pathways

 PhotorespirationPhotorespiration: A wasteful process that produces : A wasteful process that produces

no ATP or sugars no ATP or sugars

Occurs in hot, dry climatesOccurs in hot, dry climates

VII Alternate pathways to avoid photorespiration VII Alternate pathways to avoid photorespiration

 CC44 plants plants

Examples: corn, sugarcaneExamples: corn, sugarcane

Fix COFix CO22 with alternate carbon molecule in different types of with alternate carbon molecule in different types of

cells

cells

Net productivity about 2-3 times CNet productivity about 2-3 times C33 plants plants

 Crassulacean-Acid Metabolism (CAM)Crassulacean-Acid Metabolism (CAM)

You should now be able to

1

1 Explain the general chemical equationExplain the general chemical equation

1

1 Recognize and define reduction and oxidation equationsRecognize and define reduction and oxidation equations

2

2 Identify the parts of the plant cell involvedIdentify the parts of the plant cell involved

3

3 Identify the processes/stages of photosynthesis and Identify the processes/stages of photosynthesis and where each occurs

where each occurs

4 Generally describe the events of the Light ReactionGenerally describe the events of the Light Reaction

5

5 Generally describe the events of the Calvin cycleGenerally describe the events of the Calvin cycle

6

6 Explain the importance of ATP and NADPHExplain the importance of ATP and NADPH

7

7 Describe photorespiration and the need for alternate Describe photorespiration and the need for alternate pathways

pathways

Photosynthesis (a) (b) (c) (d) (h) (e) (f) (g) chemiosmosis sugar (G3P) by C6H12O6

to produce using

reduce NADP+ to

are passed down

and and then H2O is split

light-excited electrons of chlorophyll

CO2 is fixed to RuBP in which in which to chemical energy converts includes both producing Sun

energy ReactionLight Calvin Cycle The electron transport chain NADPH

Splits to C molecule

ATP O2 is

http://www.youtube.com/watch?v=Q_1mxZdF2T Y&feature=related