Maintaining Dynamic Maintaining Dynamic EquilibriumEquilibrium

Photosynthesis Photosynthesis

and Respirationand Respiration

The Journey of a Carbon The Journey of a Carbon AtomAtom

Hi…I’m a Carbon Atom and I will be your Hi…I’m a Carbon Atom and I will be your guide through this unit on photosynthesis guide through this unit on photosynthesis and respiration. and respiration.

You will see that these two processes have You will see that these two processes have a lot to do with each other.a lot to do with each other.

PhotosynthesisPhotosynthesis

COCO22 + H + H22O + Sunlight CO + Sunlight C66HH1212OO66 + O + O22

RespirationRespiration

CC66HH1212OO6 6 + O+ O2 2 COCO22 + H + H22O + Energy O + Energy

Chemical EquationsChemical Equations

Enzymes

Enzymes

What do you notice about their two chemical equations?What do you notice about their two chemical equations?

My Story…My Story…

As you know, carbon molecules like me are As you know, carbon molecules like me are found in many different places. We are found in many different places. We are found in inorganic compounds like COfound in inorganic compounds like CO2 2

When I am with my friend the Hydrogen When I am with my friend the Hydrogen atom in a compound, it is known as atom in a compound, it is known as organic. For example when we appear organic. For example when we appear together in glucose Ctogether in glucose C66HH1212OO66..

One day I was happily floating around in One day I was happily floating around in the air as part of a carbon dioxide the air as part of a carbon dioxide molecule when I was sucked up into the molecule when I was sucked up into the leaf of a blueberry bush!leaf of a blueberry bush!

This was a little bit of a disappointment This was a little bit of a disappointment because I was enjoying floating around on because I was enjoying floating around on the breeze on a nice summer day!the breeze on a nice summer day!

The Leaf…The Leaf…is where I entered the plant. The stoma on the is where I entered the plant. The stoma on the

bottom side of the leaf are tiny holes. They bottom side of the leaf are tiny holes. They open and close with the help of guard cells to open and close with the help of guard cells to exchange gases and water with the outside exchange gases and water with the outside environment.environment.

Conveniently, the leaf is the part of the plant Conveniently, the leaf is the part of the plant where photosynthesis takes place.where photosynthesis takes place.

Into the Chloroplast!Into the Chloroplast! When I was sucked into the chloroplast I When I was sucked into the chloroplast I

knew I wouldn’t be part of carbon dioxide knew I wouldn’t be part of carbon dioxide for long!for long!

Light ReactionsLight Reactions You see, photosynthesis takes place in a specialized You see, photosynthesis takes place in a specialized

organelle found in plant cells called the chloroplast. organelle found in plant cells called the chloroplast.

The first phase takes place in the grana, where the The first phase takes place in the grana, where the pigment chlorophyll is stored. The sunlight shines on pigment chlorophyll is stored. The sunlight shines on the chlorophyll and this splits molecules of water right the chlorophyll and this splits molecules of water right in half!in half!

GranaGrana

Dark ReactionsDark Reactions

The hydrogen atoms from the water are carried The hydrogen atoms from the water are carried out of the grana into the stoma where I am out of the grana into the stoma where I am waiting with my oxygen friends. waiting with my oxygen friends.

StromaStroma

Sugar!!Sugar!!Hydrogen is attached to me and my friend Hydrogen is attached to me and my friend

oxygen and you know what that means… oxygen and you know what that means… sugar!sugar!

Voila…I have gone from inorganic COVoila…I have gone from inorganic CO22 to an to an organic carbohydrate!organic carbohydrate!

Glucose – CGlucose – C66HH1212OO66

That’s photosynthesis…let’s recap…That’s photosynthesis…let’s recap…

Photosynthesis EquationPhotosynthesis Equation

__CO__CO22 + __H + __H22O + Sunlight CO + Sunlight C66HH1212OO66 + __O + __O22

The blueberry bush will use dehydration synthesis to attach me The blueberry bush will use dehydration synthesis to attach me to many other glucose molecules for storage. Do you know to many other glucose molecules for storage. Do you know

what this polysaccharide is called??what this polysaccharide is called??

enzymes

I won’t stay for longI won’t stay for longSTARCHSTARCH

So here I sit, now I am part of a starch So here I sit, now I am part of a starch molecule that is stored in the blueberry molecule that is stored in the blueberry on this bush…on this bush…

This sounds lovely…BUT there is a deer This sounds lovely…BUT there is a deer sniffing at the bush and it looks like he sniffing at the bush and it looks like he just might take a bite!just might take a bite!

I’m in that berry…

Well here I go…Well here I go…

Turns out that deer was hungry and I am Turns out that deer was hungry and I am on the move again!on the move again!

He took a large bite and all of a sudden I He took a large bite and all of a sudden I am in the deer’s mouth!am in the deer’s mouth!

Digestion…Digestion… That deer chewed me up nice and good and That deer chewed me up nice and good and

now I am on the way down his esophagus and now I am on the way down his esophagus and into the stomach. into the stomach.

You know since I am now part of a starch You know since I am now part of a starch molecule I am going to be broken down by molecule I am going to be broken down by amylase into one molecule of glucose again. amylase into one molecule of glucose again. Just like the good old days back in the leaf!Just like the good old days back in the leaf!

When I am digested water is added to break When I am digested water is added to break the starch molecule into it’s building blocks. the starch molecule into it’s building blocks. Do you remember the name of this process?Do you remember the name of this process?

HydrolysisHydrolysis

amylaseamylase

Starch + HStarch + H22O Glucose O Glucose

Transport…Transport…

Now that I am a single glucose molecule Now that I am a single glucose molecule I can be absorbed into the blood stream I can be absorbed into the blood stream of the deer. of the deer.

I will be carried to a cell that needs I will be carried to a cell that needs energy…this is the life process we call energy…this is the life process we call transport.transport.

TROUBLE!TROUBLE!

This deer has come in contact with a This deer has come in contact with a hunter!! He must run to get away!hunter!! He must run to get away!

Into a muscle cellInto a muscle cell

The glucose molecule I am part of is The glucose molecule I am part of is sucked up into a muscle cell! Glucose sucked up into a muscle cell! Glucose will be used to help this deer run faster will be used to help this deer run faster and escape the hunter!and escape the hunter!

The muscle cell will use the glucose The muscle cell will use the glucose molecule to create energy to keep up its molecule to create energy to keep up its hard work through the metabolic reaction hard work through the metabolic reaction called cellular respiration.called cellular respiration.

Cellular RespirationCellular Respiration

These muscle cells need a lot These muscle cells need a lot of energy to keep the deer of energy to keep the deer moving fast! moving fast!

They are loaded with They are loaded with mitochondria, the organelle mitochondria, the organelle where cellular respiration where cellular respiration takes place.takes place.

Respiration EquationRespiration Equation

CC66HH1212OO6 6 + __O+ __O2 2 ____ COCO22 + __H + __H22O + 36 ATPO + 36 ATPenzymes

Energy for cells to do work!!!ATP is like a mousetrap!

Step one: GlycolysisStep one: Glycolysis

Once my glucose molecule enters the cytoplasm of Once my glucose molecule enters the cytoplasm of the muscle cell, it is split apart during a process called the muscle cell, it is split apart during a process called glycolysis. This only makes 2 ATP molecules and glycolysis. This only makes 2 ATP molecules and makes me part of one of two pyruvic acid molecules.makes me part of one of two pyruvic acid molecules.

Step two: Krebs CycleStep two: Krebs Cycle

Now part of pyruvic acid I enter the Now part of pyruvic acid I enter the mighty mitochondria where I will really mighty mitochondria where I will really supply some energy! supply some energy!

Together with oxygen the deer has been Together with oxygen the deer has been breathing in from the atmosphere we will breathing in from the atmosphere we will make 34 more ATP molecules to keep make 34 more ATP molecules to keep his legs going!his legs going!

COCO22 Again! Again!

Once the ATP molecules Once the ATP molecules are made I become part of a are made I become part of a waste product carbon waste product carbon dioxide!dioxide!

I am together with oxygen I am together with oxygen once again as COonce again as CO22! !

Amazing how fast I have Amazing how fast I have come full circle!come full circle!

Out into the atmosphere!Out into the atmosphere!

The deer has no use for carbon dioxide The deer has no use for carbon dioxide so the carbon dioxide molecule is carried so the carbon dioxide molecule is carried by the blood to the lungs and whoosh! I by the blood to the lungs and whoosh! I am exhaled out into the summer breeze am exhaled out into the summer breeze once again…just in time to see the deer once again…just in time to see the deer escape the hunter!escape the hunter!

I am glad I could help!I am glad I could help!

Busy Day!Busy Day!

So as you can see carbon atoms have a So as you can see carbon atoms have a very important job and we are constantly very important job and we are constantly changing form!changing form!

A Cycle…A Cycle…

I started the day as a gas in the air (COI started the day as a gas in the air (CO22)) I was sucked up into a leaf and during I was sucked up into a leaf and during

photosynthesis became part of glucose photosynthesis became part of glucose (C(C66HH1212OO66))

A deer ate me and used me for energy to A deer ate me and used me for energy to escape a hunter! During this process of escape a hunter! During this process of cellular respiration I was converted back into cellular respiration I was converted back into COCO22

This will all happen to me again before the day This will all happen to me again before the day is through!is through!

A Cycle…A Cycle…Oxygen and Glucose

Carbon Dioxide and Water

Energy IN

ATP

Energy OUT