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Trapping EnergyHave you ever used a solar-powered calculator? No matter where you go, as long as you have a light source, the calculator works. You never have to put batteries in it.

Section 8-2

Interest Grabber

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Interest Grabber Answers

1. A solar-powered calculator uses solar cells that are found in rows along the top of the calculator. Into what kind of energy is the light energy converted so that the calculator works?

They convert light energy into electrical energy.

Section 8-2

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Interest Grabber Answers

2. Recall that plants use light energy from the sun to make food. Into what kind of energy is the light energy converted by plants?

Plants convert light energy into chemical energy.

Section 8-2

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Interest Grabber Answers

3. Most plants, no matter what size or shape they are, have some parts that are green. Which parts of a plant are usually green?

Leaves are green, as are some stems.

Section 8-2

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Interest Grabber Answers

4. What does the green color have to do with the plant’s ability to convert light energy into the energy found in the food it makes?

The green color is the pigment chlorophyll, which absorbs light energy from the sun and converts it to chemical energy in the process of photosynthesis.

Section 8-2

REACTIONS of PHOTOSYNTHESIS

8-2

http://vilenski.org/science/safari/cellstructure/chloroplasts.html

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

REMEMBER CELL BIO

Atoms are the basic unit of MATTER:

A NUCLEUS contains ______________ ______________

______________ orbit nucleus in

ENERGY LEVELS

PROTONS (+)NEUTRONS

ELECTRONS (-)

Atoms differ in numbers of protons, neutrons, &

electrons

Image from: http://www.uic.edu/classes/bios/bios100/summer2004/lect02.htm

Atoms that have gained or lost electrons have anelectric charge andare called__________

They are writtenwith a + or –next to theirsymbol

IONS Na+

Cl-

1.____________2.____________3.____________4.____________5.____________6.____________

Atoms/ions important for living things

Carbon - C

Oxygen - OHydrogen - HNitrogen - NSulfur - S

Phosphorus - P

ATOMS CAN JOIN TOGETHER TO MAKE MOLECULES

Ex: Joining 2 HYDROGEN

atoms with 1 OXYGEN atom makes ________

WATER

Image by: Riedell

A chemical formula tells what kind of molecules and how many are in a molecule

EX: ________H2O

________________ = kind of chemical reaction in which molecules are produced by joining smaller molecules together

2 H2 + O2 → 2 H20

SYNTHESIS

2 water molecules

Hydrogen molecule oxygen molecule

An chemical equation tells what happens in a chemical reaction when molecules interact.

NaOH + HCl → NaCl + H20

______________ _______________Molecules that react Molecules that are

produced

products→reactants

http://www.epa.gov/region5/superfund/ecology/images/fishcartoon.gif

Chemical reactions need help to get started

EX: A fire needs a match to get it started.

http://www.chuckwagondiner.com/art/matches.jpghttp://plato.acadiau.ca/COURSES/comm/g5/Fire_Animation.gif

IT’S LIKE PUSHING A SNOWBALL UP A HILL . . . Once you get it up there, it can roll down by itself

Energy required to get a chemical reaction started

= _________________ energy

Image from: Pearson Education Inc, publishing as Pearson Prentice Hall. All rights reserved

ACTIVATION

REACTANTSPRODUCTS

ACTIVATIONENERGY

CATALYSTS HELP CHEMICAL REACTIONS HAPPEN FASTER

Catalysts work by ____________ theactivation energy required to get a chemical reaction started.

Image from: Pearson Education Inc, publishing as Pearson Prentice Hall. All rights reserved

DECREASING

CATALYSTS in Living Things

In living systems PROTEINS called __________ act as catalysts to control chemical reactions.

Image from: http://www.hillstrath.on.ca/moffatt/bio3a/digestive/enzanim.htm

SEE ANIMATIONof AMYLASE

ENZYMES

Remember from

CELL BIO

http://www.newtonswindow.com/problem-solving.htmhttp://www.tvdsb.on.ca/saunders/courses/online/SBI3C/Cells/Protein-Structure03.jpgImage from: http://www.hillstrath.on.ca/moffatt/bio3a/digestive/enzanim.htm

ENZYMES are PROTEINS that make chemical reactions happen faster

PROTEINS ACT AS ENZYMES

ENZYMES fit together with _____________ (reactants) like a lock and key to form an____________________________.

__________are released and enzyme is free to help again

http://www.biologie.uni-hamburg.de/b-online/library/cat-removed/enzyme_.gif

SUBSTRATES

ENZYME-SUBSTRATE COMPLEX

PRODUCTS

See a video about enzyme reactions

Video 4Enzymatic Reactions 2D

Many enzyme NAMES end in _____and the beginning of the name tells what it doesDNA Polymerase= “polymerizes” joins monomers to make DNA

Protease= breaks down proteins

ATP synthase= synthesizes ATP

-ASE

Go to Section:

8–2 Photosynthesis: An Overview

A. Investigating Photosynthesis

1. Van Helmont’s Experiment

2. Priestley’s Experiment

3. Jan Ingenhousz

B. The Photosynthesis Equation

C. Light Pigments

Section 8-2

Section Outline

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

THE BIG PICTURE

These 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

Go to Section:

See a video clip about PHOTOSYNTHESIS(8B)

PHOTOSYNTHESIS

Light-Dependent Reaction

Light-Independent Reactions

Light & Water

oxygen

ATP

NADPH

Carbon Dioxide (CH2O)n

Calvin Cycle

PHOTOSYNTHESIS: Reactants & Products

LIGHT ENERGY

CO2 + H2O SUGARS + O2

Sunlight is made upof many different_______________of light

Your eyes “see”different wavelengths asdifferent ___________

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

wavelengths

colors

Sizes of Wavelengths

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

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

pigments

By: VanderWal

The main energy absorbing moleculein green plants is___________________

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

CAROTENOIDS

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

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

CHLOROPHYLL

Carotenoids are what you see when chlorophyll disappears in the fall

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

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 ________wavelengths, buteven more____________light.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 ______light and even more_________ light

Chlorophyll a Chlorophyll b

red

Blue-violet

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

BUT . . . .

Myth:

Chlorophyll b

Chlorophyll a

Absorption of Light byChlorophyll a and Chlorophyll b

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

Chlorophyll a & b______________absorb_______________wavelengths oflight

do NOT

green

Why are plants green?BECAUSE…Chlorophyll _____________light very well in the __________________regions and _________ lightin the green regions of spectrum.

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

absorbs

blue-violet and red

reflects

We “see” reflected light

Light wavelengths that are reflected

bounce back to your eyes . . .

so leaves “LOOK” green.

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

___________________________________

When you see a plant with yellow flowers and green leaves, the plant is reflecting ____________________________wavelengths of light

yellow and green

By: VanderWal

When you ______ a plant with yellow and purple flowers, the plant is _____________ yellow and purplewavelengths of light

By: VanderWal

reflecting

see

Plants ________________ mainly___________________________ wavelengths of lightfor photosynthesis.

red and blue-violet

By: VanderWal

absorb and use

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

SOUTH DAKOTA SCIENCE STANDARDS

Chapter 8 - Photosynthesis: The students will be able to:• explain the biochemical processes that a plant

uses in photosynthesis• explain the role ADP-ATP cycle has within the

chloroplast of the cell (9-12.L.1.1)• explain the light reaction (9-12.L.1.1)• explain the steps of photophosphorylation and

the Calvin Cycle (9-12.L.1.1)

SOUTH DAKOTA CORE SCIENCE STANDARDS

9-12.L.1.1. Students are able to relate cellular functions and processes to specialized structures within cells.

• Photosynthesis and respirationATP-ADP energy cycle Role of enzymesMitochondriaChloroplasts

LIFE SCIENCE:Indicator 1: Understand the fundamental structures, functions, classifications, and mechanisms found in living things

Core High School Life SciencePerformance Descriptors

High school students performing at the

ADVANCED level:

explain the steps of photophosphorylation and the Calvin Cycle;

analyze chemical reaction and chemical processes involved in the Calvin Cycle and Krebs Cycle;

predict the function of a given structure;

High school students performing at the

PROFICIENT level:

describe and give examples of chemical reactions required to sustain life (…role of enzymes)

describe and give examples of chemical reactions required to sustain life (hydrolysis, dehydration synthesis, photosynthesis, cellular respiration, ADP/ATP, role of enzymes);

describe the relationship between structure and function

High school students performing at the

BASIC level

name chemical reactions required to sustain life (… role of enzymes)

name chemical reactions required to sustain life (hydrolysis, dehydration synthesis, photosynthesis, cellular respiration, ADP/ATP, role of enzymes);

recognize that different structures perform different functions;

SOUTH DAKOTA ADVANCED SCIENCE STANDARDS

9-12.L.1.1A. Students are able to explain the physical and chemical processes of photosynthesis and cell respiration and their importance to plant and animal life. (SYNTHESIS)

Examples: photosystems, photophosphorylation, Calvin Cycle and Krebs Cycle

LIFE SCIENCE:Indicator 1: Understand the fundamental structures, functions, classifications, and mechanisms found in living things.