Your Life

Depends on It!!!

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What do living organisms do with their energy?

(Create a verbal list with your table partner.)

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Energy is the ability to do work; work is a force on

something exerted over a certain distance.

So energy is often expressed as forces moving from place

to place which cause CHANGES which can sometimes be

noticed or measured.

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Energy is neither created or destroyed it

simply changes from one form to another.

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Wind to electricity

Chemical to mechanical

Food to mechanical

Solar to food

Nuclear to heat

Others? Yes lots!

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SUN

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What is a producer?

An example?

What is a consumer?

An example?

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PHOTOSYNTHESIS

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YOU DEFINE IT:

Photo means ___________.

Synthesis means _______________.

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*A quick word about these molecules. ATP is

the fundamental ENERGY molecule for almost

all cell functions. When your cell needs to do

ANYTHING requiring energy (or cell work) it

will ‘burn’ ATP molecules.

*Heres what they look like-------

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triphosphate adenosine

adenosine diphosphate

tri=3

di=2

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phosphate removed

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*When the last “P” is broken off, energy is transfered

which allow your cells to:

*> make molecules

*> transport molecules

*> send chemical signals

*> reproduce

*ATP is to your cells as is to your house.

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*When the last “P” is broken off, energy is released

which allow your cells to:

*> make molecules

*> transport molecules

*> send chemical signals

*> reproduce

*ATP is to your cells as electricity is to your house.

**Right NOW, I mean RIGHT NOW, your body is using

TRILLIONS of molecules of ATP for all your energy needs!!!

*Crazy, eh? Take a moment and give ‘em a pat on the

proverbial head

ATPs

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*You will notice ATP appearing often in this energy unit

in both photosynthesis and respiration.

*Keep in mind what it is used for; sometimes it is USED

for the cell to do things: ATP ADP

*Other times it is stored: ADP ATP

Okay, back to Photosynthesis:

What requirements do autotrophs have in order to feed themselves? You and your table

partner come up with the 3 main needs!

HOPEFULLY YOU SAID….

WATER Carbon Dioxide

SUNLIGHT

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And what kind of food do they makes? Eggs, waffles, steak? JUST KIDDING! Think of the BIG 4. Which macromolecule

might they produce?

DID YOU GUESS RIGHT…

CARBOHYDRATES! Specifically

sugar in the form of glucose.

Sugar is the molecule that starts the food

chain, for it is sugar that provides chemical

energy to the plants and to the organism

that eat the plants (heterotrophs) either

directly or indirectly.

Sugar is used by plants for chemical energy

and as a structural molecule………

SUGAR, OH HONEY HONEY

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CELLULOSE

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SUGAR

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2 2 3 6 3 2

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Roots are not exposed to sunlight,

therefore there is no use for chloroplasts to be

present in roots.

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GIVEN:

•Elodea plant is an aquatic plant

•Just like all plants it does

photosynthesis

•Bromothymol blue is an

indicator for Carbon Dioxide gas

How can we test the Elodea to

determine if photosynthesis is

taking place?

LET’S DO AN EXPERIMENT!

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LIGHT DEPENDENT REACTION

LIGHT INDEPENDENT REACTION

*Dependent

*Light energy is captured by the pigment “chlorophyll” and used to split water.

*When the water is “split” oxygen is given off as a waste product, and the energy from the light is transferred in to the hydrogen electrons to make two types of cellular energy know as ATP and NADPH.

*ATP and NADPH are energy molecules that are used to drive the second reaction.

*Dependent

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*Light energy is absorbed by the

chlorophyll and it is used to split

water

*O2 oxygen is released (as a waste

product)

*The energy from the sun is then

transferred into an ATP molecule by

using an excited H atom.

*Dependent

*OK fine, so WHERE’S THE

SUGAR??!!

.. It appears

in the next

step, Oh

curious one

*Independent

*Energy originally from the light reaction in the form of cell energy molecules ATP and NADPH combine with carbon dioxide from the air to make the 3-carbon sugar (C3H6O3.)

• Basically H + CO2 (with energy) = C3H6O3.

*Independent

*There are a series of complex chemical reactions that accomplish this process; taken together they are known as the Calvin Cycle named after the scientist that discovered these steps.

*The resulting 3-carbon sugar produced in the Calvin Cycle is then used by the plant to make other organic compounds such as the monosaccharide (glucose) or the polysaccharide (starch.)

*As before, find all these molecules in the next picture

*Independent

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*What do the building materials represent in the

photosynthesis equation?

*What do the generators represent?

*What do the carpenters represent?

*What do the finished homes represent?

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*Look for –

*Starting and ending molecules

* Interactions with atmosphere

*MAJOR product??

* carbohydrates

*By product??

*oxygen

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WORK ON THE PHOTOSYNTHESIS BREAKDOWN SHEET. REFER TO THE

DETAILED EXPLANATIONS IF YOU DO NOT KNOW THE ANSWERS.

KEEP THIS IN MIND- WHERE DOES EACH PART OF THE PHOTOSYNTHESIS

EQUATION COME FROM?

Carbon dioxide + Water + Light Energy Oxygen + Sugar

Given off in the

light dependent

reaction

From the light

independent

reaction and the

atmosphere From atmosphere (organisms) From the Sun

From rain or aquifer

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WHAT DO YOU THINK MIGHT AFFECT THE

RATE/SPEED AT WHICH PHOTOSYNTHESIS WILL

OCCUR?

HOW CAN WE TEST IT?

LET’S DO AN EXPERIMENT!

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SO WHAT IS NEXT?

After photosynthesis has

produced sugar and released

oxygen…the plants cells use

the sugar and oxygen in a

process called

________________________

which then provides energy

for the entire cell!

What cycle is this ?

(You just saw it recently!!)

CELLULAR RESPIRATION

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