Understanding PhotosynthesisChapter 8

Academic Biology

http://www.science.siu.edu/plant-biology/PLB117/JPEGs%20CD/0076.JPG

Did you know

?

Research into PHOTOSYNTHESIS

began centuries ago with this

simple question:

When a tiny seed grows into a

huge plant, where does all the

“new plant” come from?http://www.nofretete-page.de/gemischtNeu/TN_plant_grow_w.JPG

EXPERIMENTS TO FIND OUT

Then he planted the seedling in the pot and watered

it regularly. At the end of 5 years the _____________

__________about 75 kg, but the mass of the _________ was almost ________________.

http://www2.nsta.org/Energy/find/primer/primer2_3.html

He decided the “increase in plant” had to come from the ________… that was the only thing he had added!

In 1643-a Belgian physician ___________________ determined the mass of a pot of dry soil and a small seedling.

Jan Van Helmont

seedling hadgained

soil unchanged

WATER

EXPERIMENTS TO FIND OUT

Plants use _______ and ______ dioxide to make ___________________

http://www2.nsta.org/Energy/find/primer/primer2_3.html

Van Helmont didn’t realize the major contribution to the mass of his tree was something hecouldn’t see…__________________ from the air.carbon dioxide

water carbonCarbohydrates

EXPERIMENTS TO FIND OUT1771- An English minister,

_________________________,

discovered that a flame burning

in a closed jar would die out.

If he placed a __________ in the

jar and allowed a few days to

pass, the candle could be lit again.

The plant produced something “required for burning” that the candle used up

http://www2.nsta.org/Energy/find/primer/primer2_7.htmlhttp://www2.nsta.org/Energy/find/primer/primer2_8.html

We now know it was …____________OXYGEN

Joseph Priestley

live plant

EXPERIMENTS TO FIND OUT

1779

Dutch scientist ________________________

showed Priestley’s plant experiment only

worked if the plant was exposed to _________________ !

http://www.rgg.og.schule-bw.de/Dokus/d-faech/Biologie/Klasse%208/Bilder/Fotosynthese/Ingenhousz-Netz.JPG

Jan Ingenhousz

light

EXPERIMENTS TO FIND OUT

1961- American chemist ________________________

received the Nobel prize for

figuring out the

chemical _______________

used by plants to make sugar

http://www.bookrags.com/Melvin_Calvin

Melvin Calvin

pathway

http://www.daviddarling.info/encyclopedia/C/Calvincycle.html

THE BIG PICTUREThese experiments led to work by later

scientists who finally discovered that in the

presence of light, plants transform CO2 and water

into carbohydrates and release oxygen.

_____________ + ____________ _______________ + ____________

Carbondioxide WATER Sugars Oxygen

6 CO2_____________ + ____________ _______________ + ____________6 H2O C6H12O6 6 O2→

In addition to water and carbon dioxide,

__________________

and

__________________

are needed for photosynthesis to happen.

chlorophyll

light energy

http://fig.cox.miami.edu/~cmallery/255/255phts/255phts.htm

____________________ involves a complex series of chemical reactions, in which the product of one reaction is _____________ by the next reaction.

Photosynthesis

consumed

Reaction 1 → Product → X

Reaction 2 → Product Y

A series of reactions linked in this way is referred to as a __________________________

biochemical pathway

See a video about PHOTOSYNTHESIS 8B

PHOTOSYNTHESISLIGHT ENERGY

6CO2 + 6H2O C6H12O6 + 6O2

Did you know

?

http://www.ology.amnh.org/einstein/lightmatterenergy/light.html

http://son.nasa.gov/tass/images/cont_emspec2.jpg

Visible light is made up of many different_______________of light

Your eyes “see”different sizes ofwaves as different ___________

http://www.simontucket.com/_Portfolio/PortLarge/L_Il_Prism.jpg

wavelengths

colors

Many people think that plants are green because they absorb and use green light in photosynthesis,

BUT . . . .

Myth:

Image from: http://oogletutorials.com/wp-content/uploads/2007/12/photoshop-lesson-green-leaf-design26.gif

BUT… We “see” reflected light

Light wavelengths that are ___________

off of objects bounce back to our eyes .

That is the ___________ we “see”

Image modified from: http://www.visibledreams.net/Web/color/color_3.html

REFLECTED

COLOR

This book “looks BLUE” because the dye in this cover _______________ of the wavelengths of light _________ blue.

_______ light is ____________ to your eyes and itlooks BLUE

http://www.michaelhyatt.com/fromwhereisit/bluebook.jpg

exceptabsorbs ALL

BLUEreflected

The dye in this T shirt absorbs all of thecolors __________________________

Red wavelengths are_________________ to your eyes and theshirt looks RED

http://jacksbear.com/shop/index.php?main_page=product_info&products_id=9

except red

reflectedGO CATS!

Objects “look BLACK” because blackdye ________________ of thewavelengths of light.

When wavelengths are absorbed so is the_____________ of the wave.

That is why wearing a blackT-shirt in the summer feelswarmer than wearing a white t-shirt.

http://www.eventsonline.ca/events/vowsa/black_shirt.jpg

http://www.hotstuffspas.com/pools_files/sunanim.gif

absorbs ALL

ENERGY

The dye in white objects _____________ of the wavelengths of light.

_______ energy is ABSORBED so wearing whiteclothing is “cooler”.

REFLECTS ALL

LITTLE

http://www.hotstuffspas.com/pools_files/sunanim.gifhttp://www.12stitch.com/shop/images/options/Blank-White-Shirt.jpg

Which wavelengths of light are these Flowers REFLECTING?

Images by: VanderWal

yellowPurple & yellow

green

Image by: VanderWal

Which wavelengths of light do these LEAVES reflect?

So green leaves____________ thegreen wavelength of light.

REFLECT

Plants gather the sun’s energy with light absorbing molecules called ___________.

pigments

By: VanderWal

The main energy absorbing moleculein green plants is___________________

_________________ are plant pigments too.(These look yellow, orange, and red)

CAROTENOIDS

http://www.russianflora.com/store/images/product/custom_green_plant_35.jpg

http://www.rnzih.org.nz/images/gardenimages/carrots_d.jpg

CHLOROPHYLL

GREEN leaves have BOTH chlorophyll AND carotenoids __________________but the huge amount of chlorophyll ______the other colors and leaves usually look green

ALL THE TIME

hides

In ______, chlorophyll production slows as the trees shut down and photosynthesis stops for winter.

FALL

http://sps.k12.ar.us/massengale/ecology_notes_bi.htm

Then we can see thecarotinoid colors that are usually _______ by chlorophyll

http://www.litzsinger.org/weblog/archives/email%20AutumnTrees5%20LREC%20102605.jpg

HIDDEN

red

Chlorophyll a

Chlorophyll b

Absorption of Light byChlorophyll a and Chlorophyll b

© Pearson Education, Inc. Publishing asPearson Prentice-Hall. All rights reserved.

There are two types of chlorophyll__________________ & ___________________

Chlorophyll a absorbs the_____ & ________wavelengths best.

It absorbs very little ______ light.

Chlorophyll a Chlorophyll b

red violet

Blue

red

Chlorophyll a

Chlorophyll b

Absorption of Light byChlorophyll a and Chlorophyll b

© Pearson Education, Inc. Publishing asPearson Prentice-Hall. All rights reserved.

There are two types of chlorophyll__________________ & ___________________

Chlorophyll babsorbs some ______light and even more_________ light.

Chlorophyll a Chlorophyll b

red

Blue-violet

red

Chlorophyll a

Chlorophyll b

Absorption of Light byChlorophyll a and Chlorophyll b

© Pearson Education, Inc. Publishing asPearson Prentice-Hall. All rights reserved.

NEITHER KIND OF CHLOROPHYLL IS VERY GOOD AT ABSORBING _________ LIGHT!GREEN

That’s why leaves LOOK GREEN…..

Chlorophyll doesn’t absorb…. it ___________ GREEN light!

http://www.russianflora.com/store/images/product/custom_green_plant_35.jpg

REFLECTS

That’s why plant have other pigments (like carotenoids). They help _________ some wavelengths chlorophyll _______;

so the plant can __________ of the sun’s energy.

http://members.aol.com/diaspore/vhouse/biology/projects/photosynthesis/woida/meaning_of_light.html#question_1

USE MORE

ABSORB

DOESN’T

Chlorophyll a

Chlorophyll b

Absorption of Light byChlorophyll a and Chlorophyll b

© Pearson Education, Inc. Publishing asPearson Prentice-Hall. All rights reserved.

SO WHAT WAVELENGTHS ARE BEST FOR PHOTOSYNTHESIS?

THE ONESCHLOROPHYLLABSORBS THE BEST________ and_______________

red

Blue-violet

Pearson Education Inc, Pusblishing as Pearson Prentice Hall

Because light is a form of ___________, any molecule that absorbs light also ___________the energy from the light.

ENERGY

ABSORBS

ENERGY & ELECTRONS

When chlorophyll absorbs light, the energy is transferredto electrons in the chlorophyll molecule.

http://www.mhhe.com/biosci/pae/botany/uno/graphics/uno01pob/vrl/images/0160.gif

http://www.wjcc.k12.va.us/ROBB/Atom%20Animation%20Resources_files/image003.gif

HIGH ENERGY ____________make photosynthesis work!

ELECTRONS

Any Questions

?

Where does Photosynthesis

happen?

PHOTOSYNTHESIS HAPPENS IN CHLOROPLASTS

= sac-like

photosynthetic = stack of thylakoids

membranes

inside chloroplast

THYLAKOIDSGRANUM (pl. grana)

Image from BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006

SPACESTHYLAKOIDSPACE

STROMA

cytoplasm

http://www.science.siu.edu/plant-biology/PLB117/JPEGs%20CD/0076.JPG

Gel-filled spaceInside the thylakoid

sac

Gel-filled space inside

chloroplast surrounding

thylakoid sac

Gel-filled space OUTSIDE chloroplast but inside the cell membrane

PHOTOSYNTHESIS HAPPENS IN CHLOROPLASTS

Proteins that are part of the thylakoid

membrane organize

________________________________ into clusters called _____________________PHOTOSYSTEMS

http://www.science.siu.edu/plant-biology/PLB117/JPEGs%20CD/0076.JPG

Light absorbing PIGMENTS

LIVING THINGS NEED ENERGY CARRIERS

Molecule that carries

= _______

Molecule that carries HIGH ENERGY ELECTRONS

= ___________

ATP

NADP+

Images by Riedell

________ + _____ + _____ → ____________

HIGH ENERGY ELECTRONS require a special carrier, too

____________ is one

of the carriers that

cells use to transport

high energy electrons.

NADP+

2 e- H+

_______= nicotinamide adenine dinucleotide phosphate

Frying pan image from: BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006

PHOTOSYNTHESIS

Light-Dependent Reaction

Light-Independent

Reactions

Light & Water

Oxygen

ATP

NADPH

LIGHT-DEPENDENT REACTIONS

PHOTOSYSTEM II

ATP SYNTHASE

↓

↓

PHOTOSYSTEM I

ELECTRON TRANSPORTSYSTEM

↓INSIDE THYLAKOID SPACE

OUTSIDE THYLAKOID IN STROMA

Image modified from: Pearson Education Inc; Publishing as Pearson Prentice Hall

PHOTOSYSTEM II

It was discovered and named 1st

↓

↓

PHOTOSYSTEM I

WHY DOES PHOTOSYSTEM II COME BEFORE PHOTOSYSTEM I?

Image modified from: Pearson Education Inc; Publishing as Pearson Prentice Hall

See a video clip about the LIGHT-DEPENDENT REACTION

(Part 2) 8D

Molecules moveautomatically from“where there’s high

[ ]” to “where there’s low [

]”

Animatioin from: http://www.biologycorner.com/resources/diffusion-animated.gif

REMEMBER

REMEMBER Diffusion happens anytime

there is a difference in concentration in one place compared to another

= ________________________CONCENTRATION GRADIENT

REMEMBER

…as long as membrane will let molecule through

Diffusion can happen across membranes TOO

LIGHT-DEPENDENT REACTIONS

See an animation about the ELECTRON TRANSPORT CHAIN

SEE A MOVIEATP SYNTHASEIN ACTION

http://www.stolaf.edu/people/giannini/flashanimat/metabolism/atpsyn1.sw

http://www.stolaf.edu/people/giannini/flashanimat/metabolism/photosynthesis.swf

LIGHT DEPENDENT REACTIONRequires ______________

Molecules are part of ________________

Made up of __________________

connected by ______________________

& ___________________

Uses light energy to change

ADP + P → _______

NADP+ + 2e- + H + → _________

Breaks apart ______ molecules and releases _____________

LIGHT

ATP

THYLAKOID membranes

PHOTOSYSTEMS II & I ELECTRON TRANSPORT CHAIN

NADPHH20

oxygen

ATP SYNTHASE

PHOTOSYNTHESIS

Light-Dependent Reaction

Light-IndependentReactions

CALVIN CYCLE

Light & Water

Oxygen

ATP

NADPH

Carbon Dioxide C6H12O6

PHOTOSYNTHESIS OVERVIEW

Pearson Education Inc; Publishing as Prentice Hall

CO2 Enters the Cycle

Energy Input

5-CarbonMoleculesRegenerated

Sugars and other compounds

6-Carbon SugarProduced

Calvin Cycle

See Calvin cycleanimation

CALVIN CYCLE (also called _________________________)

____________ require ____________

Happens in _________ between thylakoidsNADPH donates _______________

ATP donates _________________

CO2 donates ______________ to make __________

LIGHT

LIGHT INDEPENDENT

ENERGY

STROMAHydrogen + electrons

Carbon & oxygenGLUCOSE

http://www.estrellamountain.edu/faculty/farabee/biobk/BioBookCHEM2.html

DOES NOT

Factors that Affect Photosynthesis____________________

Water is one of the raw materials needed, so

A shortage of water can ________________

photosynthesis

AMOUNT OF WATER

http://www.hononegah.org/departments/Anderson/cactus.JPG

Desert plants and conifers that live in dry conditions have a waxy coating on their leaves to prevent water loss.

slow or stop

Factors that Affect Photosynthesis

Photosynthesis enzymes function best between 0° C - 35° C

At temperatures above or below

this range, photosynthesis will slow or stop

Conifers in winter may carry outphotosynthesis only occasionally

TEMPERATURE

Factors that Affect Photosynthesis

____________________

More light increases rate of photosynthesis

up to a certain level until plant reaches its

maximum rate of photosynthesis

LIGHT INTENSITY

THE BIG PICTUREPHOTOSYNTHESIS provides

the _____________ we breathe

and the __________

heterotrophs (like us)

consume to survive

_____________ + ____________ _______________ + ____________

Carbondioxide WATER Sugars Oxygen

OXYGEN

sugars

Photosynthesis

includes

of

take place intakes place in uses

to produce to produce

use

Concept Map

Photosynthesis

includes

of

take place intakes place in uses

to produce to produce

use

Light-dependentreactions

Calvin cycle

Thylakoidmembranes Stroma NADPHATPEnergy from

sunlight

ATP NADPH O2 Chloroplasts High-energysugars

Section 8-3

Concept Map