Transcript Chapter 8 - canesbio

Chapter 8
Photosynthesis
8-1 Energy and Life
I. Autotrophs
-make food using sunlight
II. Heterotrophs
- obtains energy from food they consume
III. Energy is the “currency” of the cell
A. ATP
1. Adenosine Triphosphate
2. Chemical compound cells use to store energy
3. PARTS:
a. Adenine
b. 3 phosphate groups
c. Ribose
(5 carbon sugar)
8-1 Continued
4. Analogy  Fully charged battery
B. ADP
1. Adenosine Diphosphate
2. Has 2 phosphate groups
3. Chemical compound that can be converted to ATP to store energy
4. HOW?
a. Bond 1 more phosphate group
b. Energy is in the
bond between
phosphate groups
5. Analogy:
Half charged battery
C. Releasing Energy
1. Break bond of second and third phosphate group and
energy is released
2. ATP  ADP + P + Energy
3. ATP is the preferred energy source to power the cell
activities
2 Phosphate groups
ADP
D. ATP and Glucose
1. Glucose stores 90X more energy than 1 ATP molecule
2. Cells use ATP for quick energy not long term energy
3. Cells only store enough ATP for a few seconds of activity
8-2 Photosynthesis
IV. Photosynthesis
A. Process in which chloroplast convert light energy from
CO2 and H2O into O2 and high energy carbohydrates
(glucose)
B. Photosynthesis Equation
light
6CO2 +
6H2O 
C6H12O6
+
6O2
carbon dioxide +
water 
glucose
+
oxygen
C. Light and Pigments
1. Chlorophyll
a. green pigment in chloroplast that absorbs wavelengths
of light
b. 2 types: chlorophyll a and chlorophyll b
1. Absorb most wavelengths
of light except green
(why plants are green)
c. In the fall, trees reabsorb chlorophyll and the other pigments
are visible
8-3 Reactions of Photosynthesis
V. Takes place inside the Chloroplast
A. Thylakoids = saclike membranes that contain chlorophyll to
capture light
Stroma
1. granum = stacks of thylakiods
B. Stroma = fluid filled space around thylakoids
Single
thylakoid
Granum
C. Two types of reactions
1. Light Dependent
Chloroplast
2. Light Independent / Calvin Cycle / Dark Reaction
PHOTOSYNTHESIS
p208
H2O
CO2
Light
NADP+
ADP + P
Lightdependent
reactions
O2
Calvin
cycle
Sugars
VI. Electron Carriers = Energy Carriers
A. NADP+ = transport electrons (aka: Taxi)
B. H+ = high energy electrons (aka: passengers)
C. NADP+ picks up H+ and brings them elsewhere and drops them
off
D. NADPH drops off H+ for electron transfer at proteins that
starts chemical reactions
VII. Light Dependent Reaction
A. Requires light to take place
B. Takes place in thylakoids
C. Uses light to split water for H; releases O2 gas
and makes high energy electrons & ATP
D. Light strikes thylakoid; electrons excited; go to
the ETC form NADPH and ATP, respectively.
E. Lost electrons are replaced by Hydrolysis (aka
photolysis (splitting of water)
VIII. Calvin Cycle/Light Independent/
Dark Reactions
A. Does not need light to take place
B. Takes place in stroma
C. Powered by NADPH and ATP and uses 6CO2
molecules to produce high energy sugar
(glucose)
D. Six turns of the Calvin Cycle makes 1 glucose
molecule
IX. Factors Affecting Photosynthesis
A. Water shortage
1. slow/stop photosynthesis
B. Temperature
1. enzymes cause photosynthesis to speed up
2. too hot = slow/ stop photosynthesis.
C. Light Intensity
1. increase light = speeds up photosynthesis
2. decrease light = slows down photosynthesis
Chapter 9
Cellular Respiration
9-1 Chemical Pathways
I. Cellular Respiration:
A. Process by which mitochondria breaks down
glucose to make ATP
B. Cellular Respiration Equation:
6O2
+ C6H12O6 
Oxygen +
Glucose
6CO2

+
6H2O
Carbon Dioxide +
Water
p222
Electrons carried in NADH
Pyruvic Acid
Glucose
Electrons carried in
NADH and FADH2
Glycolysis
Cytoplasm
Mitochondria
C. Three Stages:
1. Glycolysis:
a. anaerobic process = NO Oxygen is required
b. Occurs in Cytoplasm
c. Breaks down glucose into 2 molecules of pyruvic
acid and produces 2 net ATP molecules
1) Produces 4 ATP but uses 2 ATP’s to start glycolysis
d. Pyruvic Acid moves into the mitochondria
2 ATP
2 ADP
4 ADP
4 ATP
2 Pyruvic acid
2. Krebs Cycle (aka. Citric Acid Cycle)
a. Aerobic Respiration = Requires Oxygen
b. Produces 2 ATP
c. Releases CO2, NADH, and FADH2
d. NAD+ and FAD are “taxis”, take electrons to the ETC
3. Electron Transport Chain
a. Aerobic Respiration = Requires Oxygen
b. Oxygen is the Final Electron Acceptor
c. Produces 32 ATP molecules
D. ATP Produced:
1. 4 from Glycolysis
(2 are used to start therefore only 2 net)
2. 2 from Krebs Cycle
3. 32 from ETC
4. Total of 38 ATP molecules or 36 net ATP
II. In the absence of Oxygen: Fermentation
A. Anaerobic Respiration: (does NOT require O2)
1. Follows glycolysis= 2ATP
2. TWO TYPES:
a. Lactic Acid Fermentation
1) In animals
2) Pyruvic Acid used NADH to make 2 molecules of Lactic Acid
pyruvic acid + NADH → lactic acid + NAD+
3) Lactic acid build up in muscles results in muscle fatigue
b. Alcoholic Fermentation:
1) Used by yeast cells
pyruvic acid + NADH → alcohol + CO2 + NAD+
III. Comparing Photosynthesis
and
Cellular Respiration
A. Photosynthesis and cellular respiration take place
in opposite directions.
Photosynthesis
Cellular Respiration
B. Photosynthesis vs. Respiration
1. Food Made
1. Food break down
2. Carbon Dioxide In
2. Carbon Dioxide Out
3. Oxygen Out
3. Oxygen In
4. Makes Glucose
4. Breaks down Glucose
5. Happens in Light
5. Day and Night
6. Only with chlorophyll
6. All living cells
7. Takes place in Chloroplast 7. Takes place in mitochondria
8-1
Organisms that make their own food are called
A. autotrophs.
B. heterotrophs.
C. decomposers.
D. consumers.
8-1
Most autotrophs obtain their energy from
A. chemicals in the environment.
B. sunlight.
C. carbon dioxide in the air.
D. other producers.
8-1
How is energy released from ATP?
A. A phosphate is added.
B. An adenine is added.
C. A phosphate is removed.
D. A ribose is removed.
8-1
How is it possible for most cells to function with
only a small amount of ATP?
A. Cells do not require ATP for energy.
B. ATP can be quickly regenerated from ADP
and P.
C. Cells use very small amounts of energy.
D. ATP stores large amounts of energy.
8-1
Compared to the energy stored in a molecule of
glucose, ATP stores
A. much more energy.
B. much less energy.
C. about the same amount of energy.
D. more energy sometimes and less at others.
8-2
The raw materials required for plants to
carry out photosynthesis are
A. carbon dioxide and oxygen.
B. oxygen and sugars.
C. carbon dioxide and water.
D. oxygen and water.
8-2
The principal pigment in plants is
A. chloroplast.
B. chlorophyll.
C. carotene.
D. carbohydrate.
8-2
The colors of light that are absorbed by
chlorophylls are
A. green and yellow.
B. green, blue, and violet.
C. blue, violet, and red.
D. red and yellow.
8-3
In plants, photosynthesis takes place
inside the
a. thylakoids.
b. chloroplasts.
c. photosystems.
d. chlorophyll.
8-3
Energy to make ATP in the chloroplast comes most
directly from
a. hydrogen ions flowing through an enzyme in the
thylakoid membrane.
b. transfer of a phosphate from ADP.
c. electrons moving through the electron transport
chain.
d. electrons transferred directly from NADPH.
8-3
NADPH is produced in light-dependent
reactions and carries energy in the form of
a. ATP.
b. high-energy electrons.
c. low-energy electrons.
d. ADP
8-3
What is another name for the Calvin cycle?
a. light-dependent reactions
b. light-independent reactions
c. electron transport chain
d. photosynthesis
8-3
Which of the following factors does NOT
directly affect photosynthesis?
a. wind
b. water supply
c. temperature
d. light intensity
9-1
The raw materials required for cellular
respiration are
a. carbon dioxide and oxygen.
b. glucose and water.
c. glucose and oxygen.
d. carbon dioxide and water.
9-1
Glycolysis occurs in the
a. mitochondria.
b. cytoplasm.
c. nucleus.
d. chloroplasts.
9-1
The net gain of ATP molecules after
glycolysis is
a. 3 ATP molecules.
b. 2 ATP molecules.
c. 3 pyruvic acid molecules.
d. 4 pyruvic acid molecules
9-1
Fermentation releases energy from food
molecules in the absence of
a. oxygen.
b. glucose.
c. NADH.
d. alcohol.
9-1
The first step in fermentation is always
a. lactic acid production.
b. the Krebs cycle.
c. glycolysis.
d. alcohol production.
9-2
The Krebs cycle breaks pyruvic acid down
into
a. oxygen.
b. NADH.
c. carbon dioxide.
d. alcohol.
9-2
What role does the Krebs cycle play in the
cell?
a. It breaks down glucose and releases
its stored energy.
b. It releases energy from molecules
formed during glycolysis.
c. It combines carbon dioxide and water
into high-energy molecules.
d. It breaks down ATP and NADH,
releasing stored energy.
9-2
In eukaryotes, the electron transport chain
is located in the
a. cell membrane.
b. inner mitochondrial membrane.
c. cytoplasm.
d. outer mitochondrial membrane.
9-2
To generate energy over long periods, the
body must use
a. stored ATP.
b. lactic acid fermentation.
c. cellular respiration.
d. glycolysis.
9-2
Which statement correctly describes
photosynthesis and cellular respiration?
a. Photosynthesis releases energy, while
cellular respiration stores energy.
b. Photosynthesis and cellular respiration
use the same raw materials.
c. Cellular respiration releases energy,
while photosynthesis stores energy.
d. Cellular respiration and photosynthesis
produce the same products.