Transcript Unit 4- Cells and Energy ATP, Photosynthesis and Cellular

UNIT 4- CELLS AND
ENERGY
ATP, PHOTOSYNTHESIS
AND CELLULAR
RESPIRATION
WHAT MAKES THESE CELLS SO
IMPORTANT TO MANY OTHER
ORGANISMS?????????

These diatoms are single
celled algae that use the
process of photosynthesis
to store chemical energy in
sugars. Animals eat
photosynthetic organisms
such as plants and algae
to get this chemical
energy. They also produce
oxygen that is required to
release much of the
chemical energy in sugars.
READ THE CAPTION ABOVE OR ON THE
POWERPOINT. WHAT THREE THINGS
MENTIONED ARE CRITICAL TO YOUR LIFE?
Energy
 Sugar
 Oxygen

WHAT IS ANOTHER NAME FOR
CARBON FIXATION?

Photosynthesis
WHY DOES CARBON NEED TO BE FIXED?

Organisms can’t live off of carbon dioxide. We
would die. Therefore photosynthetic plants /
organisms turn the CO2 into organic
compounds like carbohydrates. The plants
process the CO2 and give us glucose!!!!!
WHAT TYPES OF CARBON BASED MOLECULES
OR ORGANIC MOLECULES ARE NECESSARY FOR
ALL LIFE TO EXIST ON EARTH?
Proteins
 Carbohydrates
 Lipids
 Nucleic Acids

HOW DOES A WHALE USE THE ORGANIC
MOLECULES IT GETS FROM FEEDING ON
DIATOMS?
 Breaks them down for materials and energy
needed to maintain life.
ENERGY…………
•Energy for living things comes from food.
Originally, the energy in food comes from the
sun.
WHO ARE THESE PEOPLE???????????
Organisms that use light and energy from the
sun to make their own food are called
autotrophs or producers. For example, plants
and algae.
 Organisms that rely on other for food are called
heterotrophs or consumers. For example, you,
fish, whales, bears, etc….

AUTOTROPHS
HETEROTROPHS
CHEMOSYNTHESIS
Some animals don’t need sunlight &
photosynthesis as a source of energy.
 Chemosynthesis- process by which organisms
use chemical energy to make their food.
 Example- Deep Ocean Hydrothermal Vents.

https://www.youtube.com/watch?v=XotF9fzo
4Vo
HOW DOES THE FOOD GO FROM OUR MOUTHS
TO GIVING OUR BODY ENERGY?
ATP- Adenosine triphosphate
 Main energy currency
 ATP- molecule that transfers energy from the
breakdown of food molecules to cell processes.
 Cells use ATP for building molecules and moving
materials through active transport.
 ATP is made up of the sugar ribose, adenine, and
three phosphates.
 file:///D:/data/nsmedia/visualconcepts/60028.
htm

HOW DOES ATP WORK EXACTLY?????
Step 1- The energy carried by ATP is released when
a phosphate group is removed from the molecule.
The third bond is unstable and is easily broken.
 Step 2- Reaction takes place and the energy is
released for cell functions, meaning the third
phosphate fell off.
 Step 3- ATP (high energy) then becomes ADP
(lower energy molecule) because it just lost a
phosphate.
 Step 4-The molecules get broken down and energy
gets added.
 Step 5- Phosphate is added and it’s back to ATP!

phosphate removed
WHY IS THIS IMPORTANT?
The foods that you eat don’t contain ATP.
 The food needs to be digested and broken down
 Everything that you eat has a different calorie
amount (measures of energy) therefore different
foods produce different amounts of ATP.
 The number of ATP produced depends on what
you eat- Carbohydrate, protein, or lipid.

CARBOHYDRATES
Carbohydrates are not stored in large amounts
in your body because they are the most
commonly broken down molecule.
 The breakdown of glucose yields 36 ATP.
 Carbohydrates DO NOT provide the body with
the most ATP. Lipids do!

LIPIDS
Store the most energy, about 80% of the energy
in your body.
 When they are broken down they yield the most
ATP, 146 ATP

PROTEINS
Store about the same amount of energy as
carbohydrates, but they are less likely to be
broken down to make ATP.
 The amino acids that cells can break down to
make ATP are needed and used to build new
proteins.

FUN VIDEO

https://www.youtube.com/watch?v=V_xZuCPIH
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PHOTOSYNTHESIS
Defined as the process that captures energy
from sunlight to make sugars that store chemical
energy.
 Location- Chloroplast of plant cells.
 Chlorophyll- the molecule in the chloroplast that
absorbs the energy from the sunlight. Two main
types chlorophyll a and b that absorb mostly red
and blue light. Other pigments absorb the green.
 Green color in plants comes from the reflection
of light’s green wavelengths by chlorophyll.

Chloroplast
Leaf Cell
Leaf
Fall Foliage
CHLOROPLAST
 Two
main parts are:
Grana-
stacks of coined shaped
membranes.
Thylakoid- Inside the grana and they are
the little disks. They contain chlorophyll
and other light absorbing pigments.
Stroma- Fluid that surrounds the grana
inside the chloroplast.
Calvin
Cycle
LIGHT DEPENDENT REACTIONS
Rely / dependent on energy from the sun.
 Take place within and across the thylakoid
membrane.
 Water and sunlight are needed here.

LIGHT INDEPENDENT REACTIONS
Uses the energy transferred from the light
dependent reactions to make sugars.
 Reactions occur in the stroma
 Carbon dioxide is absorbed and used at this stage.
 Calvin Cycle- metabolic pathway found in the
stroma of the chloroplast in which carbon enters in
the form of CO2 and leaves in the form of sugar.
 ATP is produced as a final step and the enzyme
ATP synthase is responsible for making ATP by
adding phosphate groups to ADP.

THE WHOLE PROCESS……….
 Step
1- Chlorophyll absorbs energy from sunlight.
Energy is transferred along the thylakoid
membrane, water molecules are broken down, and
oxygen is released.
 Step 2- Energy carried along the thylakoid is
transferred to molecules that carry energy, like ATP
 Step 3- CO2 is added and larger molecules are
built.
 Step 4- A molecule of simple sugar (glucose) is
formed.
EQUATION FOR PHOTOSYNTHESIS
Carbon
Dioxide
Water
http://www.youtube.com/watch?v=lDwUVpO
EoE4
Glucose
Oxygen
QUESTIONS TO REVIEW
1. Where do light- dependent reactions occur?
 2. Where do the light independent reactions
occur?
 3. What two reactants are shown entering the
chloroplast?
 4. What two products are shown leaving the
chloroplast?
 5. What does the Calvin Cycle produce?

ANSWERS
1. thylakoid membrane
 2. Stroma
 3. water and carbon dioxide
 4. oxygen and sugar
 5. sugar- converts CO2 into sugar

Light Dependent Reactions
– Requires sunlight
– take place in thylakoids
– water and sunlight are
needed
– chlorophyll absorbs
energy
– energy is transferred
along thylakoid
membrane then to lightindependent reactions
– oxygen is released
Light Independent
Reactions
– Makes sugars
– takes place in stroma
– needs carbon dioxide
from atmosphere
– use energy to build a
sugar in a cycle of
chemical reactions
STAGE 1 IN DETAIL

Photosystems->Molecules that capture and
transfer energy in the thylakoid.
LIGHT DEPENDENT REACTIONS





Sugars are not made yet
Main function: capture and transfer energy
Water molecules are broken down into hydrogen ions,
electrons, and oxygen gas. Oxygen is a waste product
and sugars are not made at this point.
Energy is transferred to electrons.
Electrons are used for energy during photosynthesis
not for the cells general energy needs.
LIGHT DEPENDENT CONT.




Like a special ticket at an amusement park that can
only be used for a specific rollercoaster.
Energy-> electrons->ATP and NADPH (transferred to
the later stages)
Arrows represent energy and enzymes!
NADP= coenzyme that can accept hydrogen and acts
as an enzyme
http://www.biologyonline.org/dictionary/Nicotinamide_adenine_dinucleotide_phosp
hate
LETS PUT IT ALL TOGETHER

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
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Step 1-> Energy is absorbed from sunlight
Step 2-> Water molecules breakdown, electrons
enter, and oxygen is released as waste.
Step 3-> Hydrogen ions are transported across
the thylakoid membrane
Step 4-> Chlorophyll absorbs energy from
sunlight
Step 5-> NADPH is produced when electrons are
added to NADP+
STEPS 6 AND 7!!!
Step 6-> Hydrogen ions diffuse through a
protein channel
 Step 7-> ADP is changed into ATP when
hydrogen ions flow through ATP synthase
(enzyme).

CALVIN CYCLE
Does not need sunlight
 Produces sugars
 Energy sources are ATP and NADPH
 Energy that is needed for a series of chemical
reaction is called the Calvin Cycle, named after
a scientists- Melvin Calvin.

STEPS
1. CO2 is added to the 5 carbons that are already
there making a 6 carbon sugar
 2. ATP and NADPH is used from LDR to split the six
carbons into 2 groups of 3.
 3. Three carbon molecules exit. After they both exit
they bond together to form glucose.
 4. Three carbon molecules are recycled and changed
back to five carbon molecules by energy from ATP.

LIGHT INDEPENDENT / CALVIN CYCLE- INSERT
INTO NOTES

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
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Occur in the stroma
A molecule of glucose is
formed as it stores some of
the energy captured from
sunlight.
carbon dioxide molecules
enter the Calvin cycle
energy is added and carbon
molecules are rearranged
a high-energy three-carbon
molecule leaves the cycle
CALVIN CYCLE CONT.
A molecule of glucose is
formed as it stores some
of the energy captured
from sunlight
 Two three-carbon
molecules bond to form
a sugar
 Remaining molecules
stay in the cycle

VIDEOS
http://highered.mcgrawhill.com/sites/0072437316/student_view
0/chapter10/animations.html#
 http://dendro.cnre.vt.edu/forestbiology/p
hotosynthesis.swf

CELLULAR RESPIRATION!!
 Releases
chemical energy from
sugars and other carbon based
molecules to make ATP when oxygen
is present.
BY THE TIME YOU REACH 16
YOU HAVE TAKEN ABOUT 200
MILLION BREATHS
Breathe in oxygen and
the oxygen releases
energy in sugars and
other carbon based
molecules
ATP
 Animals
use cellular respiration
 Plants use photosynthesis
 Breakdown food-> ATP
 Aerobic-> Need Oxygen
 Anaerobic= no oxygen
 Takes place in the Mitochondria
 After
you eat and the food is broken
down into glucose then the glucose
needs to get broken down by
glycolysis (2-3 carbon chains, ATP),
which takes place in the cytoplasm
and is anaerobic.
GLYCOLYSIS- DRAW INTO
NOTES
2 STAGES
Stage
1= Krebs Cycle
Stage 2= Electron Transport
KREBS CYCLE
 Produces
molecules that
carry energy to
the second part.
 Occurs in the
matrix of
mitochondria
1
mitochondrion
ATP
matrix (area enclosed
by inner membrane)
and
6CO
2
energy
2
3
energy from
glycolysis
and
6O 2
inner membrane
ATP
and
6H 2O
4
STEP 1

2- 3 carbons from
glycolysis through
pyruvate enter the
cells matrix
 Pyruvate is broken down before the
Krebs cycle.
 carbon dioxide released
 NADH produced
 coenzyme A (CoA) bonds to
two-carbon molecule
STEP 2
 Energy
carrying molecules transfer
energy through the matrix.
STAGE 3
 Energy
is transferred to the
chain of proteins (electron
transport chain)
STAGE 4
Large
# ATP is made. Heat and
H2O are released as waste
products.
END RESULT

38 ATP molecules are made from 1 glucose
molecule-> 2 glycolysis and 34/36 come from
cellular respiration.
PRODUCT CREATED IN THE BODY VIA
METABOLISM AND IS THE END PRODUCT
OF GLYCOLYSIS

Pyruvate-> enzyme that speeds up the
phosphates
WHAT ENZYME IS DIRECTLY ASSOCIATED WITH
THE KREBS CYCLE?

Pyruvate and coenzyme a
WHAT GETS FORMED?

Citric acid
Photosynthesis
Cellular Respiration
Location
Chloroplast
Mitochondria
Reactants
CO2 and H2O
C6H12O6 and O2
Products
C6H12O6 and O2
CO2 and H2O
Electron
Transport
Chain
Proteins within the thylakoid
membrane
Proteins within the inner
mitochondrial membrane
Cycle of
chemical
reaction
Calvin cycle in the stroma of
chloroplasts builds sugar
molecules.
Krebs cycle in matrix of
mitochondria breaks down
carbon based molecules.
• Fermentation allows glycolysis to continue
making ATP when oxygen is unavailable.
 Fermentation is an anaerobic process.
 occurs when oxygen is not available for cellular
respiration
 does not produce ATP
• Lactic acid fermentation occurs in muscle cells.
– glycolysis splits glucose into two pyruvate molecules
– pyruvate and NADH enter fermentation
– energy from NADH converts pyruvate into lactic acid
– NADH is changed back into NAD+
 Alcoholic fermentation is similar to lactic acid
fermentation.
 glycolysis splits glucose and the products enter
fermentation
– energy from NADH is used to split pyruvate
into an alcohol and carbon dioxide
– NADH is changed back into NAD+
– NAD+ is recycled to glycolysis
Fermentation is used in food
production.
Yogurt
Cheese
Bread