101 Lab 6 photosynthesis Tutor template 2011.pdf

8/14/2019 101 Lab 6 photosynthesis Tutor template 2011.pdf

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Plants are important!!!

Nearly everything on the planet depends on energyproduced by photosynthesis

Produces the O 2 in theatmosphere

PhotoautotrophsProduce energy through photosynthesis (plants, algae,bacteria)


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Why leaves are green..is due to the interaction of light with thechloroplasts

The electromagnetic spectrum


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Photosynthesis equation

Reactants Products

6CO2 + 6H2O C6H12O6 + 6O2light

Photosynthesis is split into two distinct reactions

Light reactions photo

Dark reactions synthesis Calvin cycle

Tracking atoms through photosynthesis


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The location of photosynthesis

Chloroplasts

Leaf cross section

Overview of photosynthesis (1)H2O is oxidised


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Overview of photosynthesis (2)

Overview of photosynthesis (3)


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What molecule absorbs light?

Chlorophyll

Chlorophyll is

located in thethylakoidmembrane

Chlorophyll absorption spectrum

Evidence thatchloroplast

pigments areinvolved in

p o osyn es s


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How a photosystem harvests lightPrimaryelectronacceptor

Reactioncenterchlorophyll

eac onCenter

Electron transfer

Photosystem

Pigment molecules

Photosystems and electronsThere are two photosystems PSI and PSII

cyclic

Acyclic involves PSIIand PSI

Cyclic involves PSI only

PSII

PSIe -

e -

PSII

PSI


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How non-cyclic electron flow generates ATP and NADPH

5

Primary e - acceptor6

Fd

H2O

2 O2

r mary e - accep or

2e -1

Pq

Cytochromecomplex

Pc4e - flow provides P700

2e -

-

NADP+reductase

NADP+ NADPH

Photosystem II

P680

Light

energy orsynthesis of

ATP Photosystem I Light

Mechanical analogy..


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Cyclic electron flow just generates ATP

Primary e - acceptor

Fd

H2O

O2

r mary e - accep or

2e -

Pq

Cytochromecomplex

Pce - flow provides P700

2e -

2e -

NADP+reductase

NADP+ NADPH

Fd

Photosystem II

P680

Light

energy orsynthesis of

ATP Photosystem I Light

Todays lab.Measuring the initial velocity of acyclic electron flow

INSTEAD of NADP + as an electron acceptor we areusing the dye DCPIP (pg 6.1 & pg 6.2)

Use class results to determine the relationshipbetween electron flow and light intensity

Sharing specs again READ INSTRUCTIONS

Table on pg 6.3 unknown vol = 120ul


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Graphs1.

AbsDraw a line throughstee est art

Light exposure (mins)

2. From class averages

REMEMBER: n a

velocity ofe- flow

dec lamp dist

se pencThink about your units

AbsorbanceIn spectroscopy the absorbance A is defined as:

= -

I = transmitted light intensityintensity of light at a specified wavelength ( ) thathas passed through a sample

0 = nc en g n ens yintensity of the light before it enters the sample

EXPLAINED by the BEER-LAMBERT LAW


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Determining an absorption spectrum

Alternative learningstyle

...http://nz.youtube.com/watch?v=_IV-E68rh18 ...


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MASTER SLIDE

FINALCHECKLIST: Assignment - name; stream number;bench (#)

Clean Up instructions on

XXX xxxxxxxxxxxxxxxxxWash hands before leaving


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101 Lab 6 photosynthesis Tutor template 2011.pdf

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