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 7 Photosynthesis: Seven things to know

1 General chemical equation (7.3-7.4)

2 Part of the plant cell involved (7.2)

3 Photosynthesis is composed of 2 processes (7.5)

4 General description of light reaction (7.6-7.9)

5 General description of Calvin cycle (7.10)

6 Importance of ATP and NADPH (7.11)

7 Alternate pathways (7.12)

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

*Cellular Respiration

Photosynthetic Organisms are autotrophs/producers

What do plants need to survive?

What are the REACTANTS for

photosynthesis?

I General chemical equation

Photosynthesis: Sun energy to chemical energy

Is this process exergonic or endergonic?

II Parts of plant cell involved

 CO 2 enters leaf through stomata

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

 Mesophyll tissue

Tissue composed of cellsTissue composed of cells containing chloroplasts containing chloroplasts

Chloroplasts contain chlorophyllChloroplasts contain chlorophyll pigment

How about

H 2 O ?

Cell

Photosynthesis Overview

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

III Photosynthesis is composed of 2 processes

 Light Reaction:

Use light energy to split water; make NADPH and ATP

 Calvin Cycle Reaction:

Incorporate light reaction products; change CO2 to

G3P to make glucose

 Oxidation-reduction (redox) reactions:

 Both take place at same time

GER!

REDOX Reactions

Transfer of electron

IV General description of light reaction

1 Capture light energy in the form of a photon with

chlorophyll pigment and excite electron in

photosystem

2 Water splits to replace lost electrons

3 Transfer electron to electron transport chain (ETC)

4 Creation of H+ concentration gradient

5 NADP+ is reduced to NADPH

6 ATP generated with ATP Synthase

Chloroplast

Thylakoid

Absorbed light

Transmitted light

Reflected light

1 Capture light energy in the form of a photon by pigments

Chlorophyll molecule

e –

Stroma (low H + concentration)

Thylakoid space (high H + concentration)

ADP + P ATP

1 Capture light energy

2 Water splits and

What have we done so far?

V General description of Calvin Cycle (aka Dark

Reaction, Light Independent)

1 Carbon fixation of CO2 and cycling of various

carbon products

2 Use of light reaction products (NADPH & ATP)

3 Production of G3P (glyceraldehade-3-phosphate)

to make glucose

The Calvin Cycle:

Fixation of CO2

1 CO 2 fixation

2 Use of light reaction products

3 Make G3P  glucose

ATP RuBP

3-PGA

C ALVIN CYCLE

6

6

6 6 P

Step Reduction

2 2

G3P

3 3

G3P

Glucose and other compounds Output:

Step Release of one

3 ADP

NADP +

6 ADP +

Importance of Calvin Cycle

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

to many other molecules

General chemical equation

Reduced

Oxidized

H 2 O

NADP + ADP P

LIGHT REACTIONS (in thylakoids)

Light

Chloroplast

VI Importance of NADPH and ATP

H 2 O

ADP P

LIGHT REACTIONS (in thylakoids)

Light

Chloroplast

NADPH ATP

H 2 O

ADP P

LIGHT REACTIONS (in thylakoids)

Light

Chloroplast

NADPH ATP

O 2

CALVIN CYCLE (in stroma)

Sugar

CO 2

NADP +

VII Alternate pathways

 Photorespiration: A wasteful process that produces

no ATP or sugars

VII Alternate pathways to avoid photorespiration

 C4 plants

 Examples: corn, sugarcane

 Fix CO 2 with alternate carbon molecule in different types of cells

 Net productivity about 2-3 times C 3 plants

 Examples: cacti, jade plants, pineapple

 Partition carbon fixation by time of day

Chloroplast distribution in

C4 vs C3 Plants

CO2 Fixation in a

CAM Plant

You should now be able to

where each occurs

pathways

Copyright © 2009 Pearson Education, Inc.

to produce using

reduce NADP + to

are passed down

H2O is split

light-excited electrons of chlorophyll

CO2 is fixed to RuBP

transport

chain

NADPH

Splits to 3 C molecule

ATP O2 is

formed

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

Show Bioflix Ch 7 Photosynthesis