Download Photosynthesis and Cellular Respiration

Chapter 8: Photosynthesis
8-1
ATP

Adenosine triphosphate (ATP) is the directly usable
form of energy for cellular processes
8-1
ATP

Energy in ATP is released when the bond between
the second and third phosphate group is broken
8-1
ATP

ADP can be “recharged” to ATP with the addition of
energy and a phosphate group
Energy
Adenosine diphosphate (ADP) + Phosphate
Partially
charged
battery
Energy
Adenosine triphosphate (ATP)
Fully
charged
battery
1.
Energy is released from ATP when
A. a phosphate group is added.
B. adenine bonds to ribose.
C. ATP is exposed to sunlight.
D. a phosphate group is removed.
8-2
Photosynthesis Overview

Method of using light energy to convert CO2 and
water into sugar (glucose) and oxygen

This is how carbon and energy enters the food chain
2.
A student is collecting the gas given off
from a plant in bright sunlight. The gas
being collected is probably
A. oxygen.
B. carbon dioxide
C. ATP.
D. water vapor.
8-2
Chloroplasts
8-2
Light-dependent Reactions



Occurs in thylakoids
Requires light to charge
electrons
– Energy from electrons
used to produce ATP and
NADPH
This energy powers the
second part of
photosynthesis, The
Calvin Cycle
8-3
Light-dependent Reactions

Take place within the thylakoid membrane
Hydrogen
Ion Movement
Photosystem II
ATP synthase
Inner
Thylakoid
Space
Thylakoid
Membrane
Stroma
Electron
Transport Chain
Photosystem I
ATP Formation
Light-dependent Reactions
8-3
3.
Which of the following is NOT involved in
the Light Dependent Reactions
A. oxygen.
B. carbon dioxide
C. ATP.
D. water
4.
Choose the correct pathway of energy,
A. Light  Electrons  ATP
B. Electrons  Light ATP
C. ATP Electrons  Oxygen
D. Water  Oxygen  ATP
Calvin Cycle (Light-independent
Reactions)


Powered by ATP and NADPH generated in
light reactions
Occurs in the stroma
The Calvin Cycle (light-independent reactions)

CO2 is carbon source for glucose (sugar)


And all other carbon compounds
This is how carbon enters the food chain
8-3
5.
What would happen if a plant was placed in
a room filled with nothing but oxygen?
A. It would grow faster
B. It would not be able to produce ATP
C. It would not be able to produce glucose
D. It would not require water
Chapter 9: Cellular Respiration
Using Chemical Energy


Plants and animals both use
glucose for metabolic fuel
Glucose is not directly usable
–
Must be converted into ATP
first
Cellular Respiration Overview



Converts glucose into ATP
Occurs in both plants and
animals
Cellular Respiration
Reaction:
–

C6H12O6 + 6O2 → 6CO2 + 6H2O
Opposite of photosynthesis
- 6CO2 + 6H2O → C6H12O6 + 6O2
6.
Which of the following is NOT a product of
cellular respiration?
A. Carbon Dioxide
B. Water
C. ATP
D. Oxygen
6.
How are cellular respiration and photosynthesis
almost opposite processes?
A. Photosynthesis releases energy and cellular
respiration stores energy.
B. Photosynthesis removes carbon dioxide from the
atmosphere and cellular respiration puts it back.
C. Photosynthesis removes oxygen from the
atmosphere, and cellular respiration puts it back.
D. All of the above
Glycolysis



Glucose  two pyruvic acid (a.k.a. pyruvate)
Occurs in the cytoplasm
Produces 2 ATP
Glucose
2 G3P
2 Pyruvate
to electron
transport chain
6.
Which substance is needed to begin the process
of glycolysis?
A. ATP
B. NADP
C. Carbon Dioxide
D. Pyruvic Acid
Aerobic Cellular Respiration


Oxygen required = aerobic
2 more sets of reactions which occur in a
specialized organelles called mitochondria
1. The Krebs Cycle
2. The Electron Transport Chain
The Krebs Cycle


A.K.A. The Citric Acid Cycle
Completes the breakdown of glucose
–

Carbon and oxygen atoms end up in CO2 and H2O,
respectively
Produces only 2 more ATP
–
but produces electron carriers NADH and FADH2
which move to the 3rd stage (E.T.C.)
The Krebs Cycle
Citric Acid
Production
The Krebs Cycle
Products (per glucose):
 6 CO2
 2 ATP
 8 NADH
to E.T.C.
 2 FADH2
6.
The Krebs Cycle takes place within the
A. Chloroplast
B. Mitochondrion
C. Nucleus
D. Cytoplasm
6.
During the Krebs Cycle
A. Hydrogen ions and oxygen form water
B. The cell releases a small amount of energy
through fermentation
C. Each glucose molecule is broken down into two
molecules of pyruvic acid
D. Pyruvic acid is broken down into carbon dioxide in
a series of reactions
Electron Transport Chain

Powered by electron carriers from the Kreb’s
Cycle
–


NADH and FADH2
Produces a total of 32 ATP
Oxygen is needed to accept electrons at the end
–
Produces water as a byproduct
The Electron Transport Chain
Hydrogen Ion Movement
Electron Transport
H+ Active Transport
H+ Diffusion
Intermembrane
Space
ATP synthase
Inner Membrane
Mitochondrial Matrix
ATP Production
Energy Tally

36 ATP for aerobic vs. 2 ATP for anaerobic
–
Glycolysis
2 ATP
–
Krebs
2 ATP
–
Electron Transport Chain
32 ATP
36 ATP
7.
Why do animals need to breathe in oxygen?
A. To convert glucose into pyruvate during glycolysis
B. To accept electrons in the electron transport
chain
C. To carry NADH and FADH2 to from the Krebs
Cycle to the E.T.C.
D.
To produce water
7.
Which of the following processes is NOT part of
aerobic cellular respiration?
A. The Krebs Cycle
B. The Electron Transport Chain
C. The Citric Acid Cycle
D. Glycolysis
Anaerobic Cellular Respiration


Also called fermentation
Some organisms thrive in environments with little or no
oxygen
–


No oxygen used = anaerobic
Results in no more ATP
–

Marshes, bogs, digestive tracts, sewage treatment tanks, etc.
The final steps in these pathways serve ONLY to regenerate
NAD+ so it can keep glycolysis running
End products such as ethanol and CO2 (yeast in
beer/bread) or lactic acid (muscle cells)
Fermentation Overview
Alcoholic Fermentation



Used by yeasts and other microorganisms
Produces carbon dioxide and ethanol
Used to make bread and alcoholic drinks (beer, wine,
etc.)
Lactic Acid Fermentation



Used by both unicellular and multicellular organisms
Lactic acid buildup in muscles causes a burning sensation
Used in the production of sour cream, cheese, yogurt, and
many other foods & beverages
Glucose
Pyruvic Acid
Lactic Acid
Fermentation Overview