Download 4.1 Chemical Energy and ATP

4.1 Chemical Energy and ATP
Cells and Energy
Material on Midterm and Keystone Module A
4.1 Chemical Energy and ATP
ELIGIBLE CONTENT
• BIO.A.1.2.1 Compare cellular structures and their functions in
prokaryotic and eukaryotic cells.
• BIO.A.1.2.2 Describe and interpret relationships between structure
and function at various levels of biological organization.
• BIO.A.3.1.1 Describe the fundamental roles of chloroplasts and
mitochondria in energy transformations.
• BIO.A.3.2.1 Compare the basic transformation of energy during
photosynthesis and cellular respiration.
• BIO.A.3.2.2 Describe the role of ATP in biochemical reactions.
4.1 Chemical Energy and ATP
The chemical energy used for most cell processes is
carried by ATP.
• All cells need some kind of energy!
– The energy usually turns low-energy reactants into
high-energy products
4.1 Chemical Energy and ATP
The chemical energy used for most cell processes is
carried by ATP.
• All cells need some kind of energy!
– Adenosine trip phosphate (ATP) is the “currency of the
cell” for energy
adenosine
tri=3
triphosphate
4.1 Chemical Energy and ATP
• ATP transfers energy from the breakdown of food
molecules to cell functions.
– Energy is released when a phosphate group is
removed.
– ADP is changed into ATP when a phosphate group is
added.
Via DEHYDRATION SYNTHESIS
phosphate removed via HYDROLYSIS
4.1 Chemical Energy and ATP
• ATP transfers energy from the breakdown of food
molecules to cell functions.
– ATP can be thought of as a fully charged battery ready
to do work
– ADP can be thought of a battery that needs to be
recharged
4.1 Chemical Energy and ATP
Multiple choice question
Eligible Content: BIO.A.3.2.2 Describe the role of ATP in
biochemical reactions.
• Which comparison between ATP and ADP is correct?
A ATP stores less chemical energy than ADP and phosphate
B ATP stores more chemical energy than ADP and phosphate
C Less energy is used to form ATP than is released from ATP hydrolysis
D More energy is used to form ATP than is released from ATP hydrolysis
4.1 Chemical Energy and ATP
The chemical energy used for most cell processes is
carried by ATP.
• Molecules in food store chemical energy in their bonds.
– Called chemical energy
• This chemical energy can be converted into the chemical
energy of ATP
• Carbohydrates are the molecules most commonly broken
down to make ATP.
– 36 ATP/1 molecule glucose
• Fats store the most energy
– 146 ATP/molecule
• Proteins are not usually broken down for energy
4.1 Chemical Energy and ATP
A few types of organisms do not need sunlight and
photosynthesis as a source of energy.
• Some organisms live in places
that never get sunlight.
• In chemosynthesis, chemical
energy is used to build
carbon-based molecules.
– similar to photosynthesis
– uses chemical energy
instead of light energy
4.4 Overview of Cellular Respiration
KEY CONCEPT
The overall process of cellular respiration converts
sugar into ATP using oxygen.
4.4 Overview of Cellular Respiration
Cellular respiration makes ATP by breaking down sugars.
• The equation for the overall process is:
C6H12O6 + 6O2  6CO2 + 6H2O
Requires oxygen and fuel (glucose)
– Produces carbon dioxide and water,
and ATP (energy)
• Converts chemical energy from one form
(sugar) to another (ATP)
4.4 Overview of Cellular Respiration
Cellular respiration makes ATP by breaking down sugars.
• Cellular respiration is aerobic, or requires oxygen.
• There are three stages
– Glycolysis
– Citric Acid cycle / Kreb’s
Aerobic stages
– Electron transport chain
take place in
mitochondria.
mitochondrion
animal cell
4.4 Overview of Cellular Respiration
• Glycolysis must take place first.
– anaerobic process (does not require oxygen)
– takes place in cytoplasm
– splits glucose into two three-carbon molecules
– Literally means “sugar splitting”
– produces two NET ATP molecules
– 2 invested; 4 produced
pyruvic acid
4.4 Overview of Cellular Respiration
Cellular respiration is like a mirror image of
photosynthesis.
• The aerobic portions take
place in the mitochondria
– 2 membranes
- Outer: separates mitochondrion
from rest of cell
- Inner: folded over (folds are
called cristae) to create high surface
area
· Reactions occur here
– Matrix
- Fluid inside
· Reactions occur here
4.4 Overview of Cellular Respiration
Constructed response question
Eligible Content: BIO.A.1.2.2 Describe and interpret relationships
between structure and function at various levels of biological
organization.
• Explain how the structure of the inner mitochondrial
membrane aids in the function of the mitochondrion.
4.4 Overview of Cellular Respiration
Cellular respiration is like a mirror image of
photosynthesis.
• The Citric Acid Cycle / Krebs cycle transfers energy to
an electron transport chain.
Krebs Cycle
1
mitochondrion
ATP
– takes place in matrix
matrix (area enclosed
and
by inner membrane) 6CO
2
– breaks down three-carbon
molecules from glycolysis
energy
– makes a small amount of
ATP
– releases carbon dioxide
– transfers energy-carrying
molecules
– Builds up H+ in matrix
2
3
energy from
glycolysis
and
6O2
inner membrane
ATP
and
6H2 O
4
4.4 Overview of Cellular Respiration
• The electron transport chain produces a large amount of
ATP.
– takes place in inner
membrane
– energy transferred to
electron transport
chain
– oxygen enters
process
– ATP produced due to
H+ flow and ATP
synthase protein
– water released as a
waste product
1
mitochondrion
matrix (area enclosed
by inner membrane)
ATP
and
6CO2
energy
2
3
energy from
glycolysis
inner membrane
and
6O2
ATP
and
6H2 O
4
Electron Transport
4.4 Overview of Cellular Respiration
Cellular respiration is like a mirror image of
photosynthesis.
• Each stage of aerobic respiration “wrings out” glucose to
produce a little more ATP
Stage
Description
Number of ATP
per glucose
1- Glycolysis
Glucose is broken down.
2
2- Citric Acid Cycle/
Kreb’s Cycle
Carbon compounds are converted
over to CO2.
2
3- Electron Transport
ATP synthase produces ATP
32-34
Total
36-38
4.4 Overview of Cellular Respiration
Cellular Respiration Review Chart
Glycolysis
What goes in
(reactant)?
What comes out
(product)?
Where does it
occur?
Citric acid
cycle/Kreb’s
Cycle
Electron
transport chain
4.4 Overview of Cellular Respiration
• The equation for the overall process is:
C6H12O6 + 6O2  6CO2 + 6H2O
• The reactants in cellular respiration are the same as the
products of photosynthesis.
4.6 Fermentation
Fermentation allows glycolysis to continue.
• 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
4.6 Fermentation
• Fermentation allows glycolysis to continue making ATP
when oxygen is unavailable.
– NAD+ is recycled to glycolysis
• Lactic acid fermentation occurs in muscle cells and some
bacteria.
– Pyruvic acid enters lactic acid fermentation
– Pyruvate is converted into lactic acid
– NAD+ created goes back to glycolysis
4.6 Fermentation
The muscle “burn”
– High intensity exercise demands more O2
– When the body is low on O2, it will switch to lactic acid
fermentation as a survival mechanism
– When your body tries to deal with the lactic acid, your
pH drops and causes the “burn”
4.6 Fermentation
Why do you get hot and sweaty?
– When exercising, you are
breaking bonds to release
energy
– During an energy
transformation, some
energy is ALWAYS lost to
heat
– When your body
temperature increases too
much, you sweat to
maintain homeostasis.
4.6 Fermentation
Fermentation and its products are important in several
ways.
• Alcoholic fermentation is similar to lactic acid
fermentation.
– Pyruvate enters alcoholic fermentation
– Pyruvic acid is split into alcohol and CO2
– Created NAD+ goes back to glycolysis
4.6 Fermentation
Fermentation is used for food production
Alcoholic
Lactic
acid
4.6 Fermentation
Multiple choice question
Eligible Content: BIO.A.3.2.2 Describe the role of ATP in
biochemical reactions.
• Which types of respiration are useful in increasing the
amount of gas bubbles most in a food product?
A Lactic acid fermentation
B Alcoholic fermentation
C Aerobic respiration and lactic acid fermentation
D Aerobic respiration and alcoholic fermentation
4.6 Fermentation
Respiration Flow Chart
4.2 Overview of Photosynthesis
Photosynthetic organisms are producers.
• Producers make their own
source of chemical energy.
• We can also call them
autotrophs
• Photosynthesis transfers light
(solar energy) into chemical
energy
4.2 Overview of Photosynthesis
• Chlorophyll is a molecule
that absorbs light energy.
chloroplast
• In plants, chlorophyll is
found in organelles called
chloroplasts.
leaf cell
leaf
4.2 Overview of Photosynthesis
• The equation for the overall process is:
6CO2 + 6H2O –—— C6H12O6 + 6O2
granum (stack of thylakoids)
1
chloroplast
6H2O
thylakoid
6CO2
3
6O2
2
energy
(fluid outside
stroma the thylakoids)
1 six-carbon sugar
4
C6H12O6
4.2 Overview of Photosynthesis
• How do materials get in the leaves?
– Little openings on the underside of a leaf called
stoma (stomata pl.)
– Specialized guard cells open and close for gas
exchange for photosynthesis to occur
4.2 Overview of Photosynthesis
Constructed response question
Eligible Content: BIO.A.1.2.2 Describe and interpret relationships
between structure and function at various levels of biological
organization.
• When temperatures become too warm, leaves close their
stomata to conserve water. How will high temperature
most likely affect the rate of photosynthesis?
4.2 Overview of Photosynthesis
Photosynthesis in plants occurs in chloroplasts.
• Photosynthesis takes place in two parts of chloroplasts.
– Thylakoids
- Membranes where chlorophyll
is
- Stack is called a granum
grana (thylakoids)
chloroplast
– Stroma
- Fluid surrounding grana
stroma
4.2 Overview of Photosynthesis
4.2 Overview of Photosynthesis
• The light-dependent reactions capture energy from
sunlight.
–
–
–
–
take place in thylakoids
water and sunlight are needed
chlorophyll absorbs energy
energy is transferred along thylakoid membrane then to
light-independent reactions
– oxygen is released
by splitting water
– “photolysis”
4.2 Overview of Photosynthesis
• The light-independent reactions make sugars.
Aka Calvin
Cycle
– take place in stroma
– needs carbon dioxide from atmosphere
– use energy from light-dependent reactions to build a
sugar in a cycle of chemical reactions
– Uses Hydrogen atoms and electrons from water in first
stage
4.2 Overview of Photosynthesis
Constructed response question
Eligible Content: BIO.A.3.2.1 Compare the basic transformation
of energy during photosynthesis and cellular respiration.
• Scientists supply plants with special water molecules
containing a heavier-than-usual oxygen isotope, oxygen18. Which of the products of photosynthesis would
contain the isotope? Explain.
4.2 Overview of Photosynthesis
Photosynthesis Review Chart
Light-dependent
reactions
Light-independent
reactions
What goes in
(reactant)?
Water
(light energy)
Carbon dioxide
What comes out
(product)?
Oxygen
Glucose
Where does it occur?
Thylakoid membrane of Stroma of chloroplast
chloroplast
Where does it get its
energy?
From light
From the light reactions
4.2 Overview of Photosynthesis
Photosynthesis Review Chart
Light-dependent
reactions
Light-independent
reactions
What goes in
(reactant)?
Water
(light energy)
Carbon dioxide
What comes out
(product)?
Oxygen
Glucose
Where does it occur?
Thylakoid membrane of Stroma of chloroplast
chloroplast
Where does it get its
energy?
From light
From the light reactions
4.2 Overview of Photosynthesis
• The equation for the overall process is:
• The reactants in photosynthesis are the same as the
products of cellular respiration.
4.2 Overview of Photosynthesis
Multiple choice question
Eligible Content: BIO.A.3.2.1 Compare the basic transformation
of energy during photosynthesis and cellular respiration.
• Which of the following best explains the relationship
between photosynthesis and cellular respiration?
A Both produce carbon dioxide and oxygen.
B Both require energy from sunlight to occur.
C The products of one are the reactants of the other.
D A plant can carry out either one process or the other, not both