Transcript Prentice Hall Biology - Teacher Pages: Teacher Pages

KREBS CYCLE
&
ELECTRON TRANSPORT
Chapter 9-2
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Chapter 9 Section 2
The Krebs Cycle and Electron
Transport
State Science Standards: S4C5PO1 Compare the processes of photosynthesis and
cellular respiration in terms of energy flow, reactants, and products
Objectives:
-Describe what happens during the Krebs
cycle
-Explain how high-energy electrons are used
by the electron transport chain
-Identify three pathways the body uses to
release energy during exercise
-Compare photosynthesis and cellular
respiration
REMEMBER:
The “fork in the road” happens following glycolysis.
OXYGEN
The presence or absence of _______________
decides which path it takes next.
Flowchart
Section 9-2
Cellular Respiration
Glucose
(C6H1206)
+
Oxygen
(02)
Glycolysis
Krebs
Cycle
We will next focus on the Krebs Cycle. This
is the path that is taken when oxygen is
present.
Image from BIOLOGY Miller and Levine; Prentice Hall Publishing
_______________
follows
KREBS CYCLE
glycolysis if oxygen is present
REMEMBER:
Glycolysis happens in
CYTOPLASM
the ________________
outside the mitochondria.
Krebs cycle happens in
_____________
MATRIX
inside the mitochondria
PYRUVIC ACID
_______________
(also called pyruvate)
enters the
MITOCHONDRION
_________________
Pyruvic acid joins
with _______________
COENZYME A
to form
ACETYL - CoA
________________
Diagram by Riedell
WHERE DO THESE GO?
Carbon dioxide is
released into the
________________
atmosphere
High energy electron
carriers move into the
ELECTRON
TRANSPORT
____________________
CHAIN
(We will come back to this later)
Citric Acid Formation:
Krebs Cycle Animation-(select #2)
2 carbon ACETYL-COA combines with a
4 carbon molecule to form a 6-carbon
citric acid
molecule called _______________
.
WHERE DO THESE GO?
Coenzyme A goes
back to pick up
another
Pyruvic acid
________________
Citric acid
completes the
____________
KREBS
CYCLE
KREBS
CYCLE
Krebs Cycle Animation-(select #3)
KREBS CYCLE
PRODUCES
3
____
1
____
1
____
4
____
WHERE DOES IT GO?
→
6 carbons in original glucose are lost
Carbon dioxide
as ________________
to atmosphere
WHERE DO THESE GO?
ATP can be used directly
energy
to supply __________
for the cell.
High energy electron
carriers move into the
ELECTRON
TRANSPORT
____________________
CHAIN
Flowchart
Section 9-2
Cellular Respiration
Glucose
(C6H1206)
+
Oxygen
(02)
Glycolysis
Krebs
Cycle
Electron
Transport
Chain
We will next focus on the Electron
Transport Chain.
WHERE DOES IT HAPPEN?
Glycolysis
KREBS
ET
Enzymes for ELECTRON TRANSPORT CHAIN
are located in the
Inner mitochondrial membrane (cristae)
___________________________
• See video 9E
• ELECTRON TRANSPORT
See video 9F
ET cont’d
ELECTRON TRANSPORT CHAIN
INTERMEMBRANE
SPACE
CRISTAE
MATRIX
Image from: BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006
Electron Transport Chain:
Electron Transport Chain Animation(select start, continue, and #1)
electrons
High-energy _____________
from __________
NADH and __________
FADH2
are passed along the electron transport
chain.
Energy from passing electrons is used
+)
Hydrogen
ions
(H
to transport _____________________
across the membrane.
Electron Transport Chain:
Electron Transport Chain Animation(select start, continue, and #3)
The pumping of H+ ions into the
INTERMEMBRANE SPACE represents
_______________________
potential energy that is harnessed to
make ATP.
As H+ ions escape through ion channels
ATP SYNTHASE
back into the matrix, ________________
spins and adds a phosphate to ADP to
ATP
form _______
Electron Transport Chain:
OXYGEN
________________
serves as the final
electron acceptor of the electron transport
chain.
At the end of the electron transport chain,
an enzyme combines the electrons with
the hydrogen ions and oxygen to form
______________
water (H2O)
Electron Transport Chain Animation-(#1 and #2)
NADH come in
High-energy electrons from ________
at beginning but electrons from _________
FADH2
come in farther down the chain.
SO:
→
FADH2 →
NADH
3 ATP’s
_____
2 ATP’s
_____
Figure 9–2 Cellular Respiration: An Overview
WHATS THE BIG PICTURE?
Electrons carried in NADH
Electrons
carried in
NADH and
FADH2
Pyruvic
acid
Glucose
Cytoplasm
Glycolysis
Electron
Transport
Chain
Krebs
Cycle
Mitochondrion
CELLULAR RESPIRATION
includes:
GLYCOLYSIS
______________________
KREBS CYCLE
______________________
ELECTRON TRANSPORT CHAIN
_______________________
GLYCOLYSIS
Happens in CYTOPLASM
______________
outside mitochondria
1 glucose
Breaks down ____________
into ________________
2 pyruvic acid (pyruvate)
Produces
2
_______
2
__________
KREBS CYCLE
MATRIX
happens in ________________
inside mitochondria
Breaks down _________________
2 pyruvic acid
Produces:
2
____
____
8____
____
2
6
ELECTRON TRANSPORT
cristae
Enzymes found in _____________
inner membrane of mitochondria
Uses high energy electrons and H+ ions
NADH
FADH2
donated by _______
and _______
32 (net) ATP
Makes ___________
OXYGEN acts a final
________
H2O
electron acceptor to produce ________
Image from BIOLOGY Miller and Levine; Prentice Hall Publishing
CELLULAR RESPIRATION
(aerobic/ with oxygen):
36 ATP
1 glucose → _______________
FERMENTATION
(anaerobic/ without oxygen):
2 ATP
1 glucose → ________________
Remember !
CARBOHYDRATES SUPPLY ENERGY
Cells burn GLUCOSE
for their energy needs
Images from: http://www.miranda.com/library.en/Images/Pictures/girls-runners.jpg
http://www.estrellamountain.edu/faculty/farabee/biobk/BioBookCHEM2.html
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EXERCISE and ENERGY
(Short term energy)
SMALL
Cells normally contain _________
amounts of ATP produced by
GLYCOLYSIS
_______________
&
__________________________
CELLULAR RESPIRATION
(only enough for a few seconds of activity)
LACTIC ACID
Once this ATP is used up_____________
fermentation can provide enough ATP
to last about ___________________.
90 seconds
EXERCISE and ENERGY
(Short term energy)
Lactic acid
Once race is over, _______________
must be broken down using oxygen.
trained
Well __________
athletes burn
lactic acid more
efficiently.
Image from:
http://www.miranda.com/library.en/Images/Pictures/girls-runners.jpg
EXERCISE and ENERGY
(LONGER term energy)
For exercise longer than 90 seconds
Cellular respiration
_____________________
is the only
way to make enough ATP.
Cellular respiration releases energy
more slowly than fermentation.
_____________
Well conditioned athletes must pace
themselves during a long race.
What happens in a long race
when the body’s glucose all
is used up?
REMEMBER
Animal cells store
GLUCOSE as
_____________
GLYCOGEN
to use later.
Image from: http://www.msu.edu/course/lbs/145/smith/s02/graphics/campbell_5.6.gif
EXERCISE and ENERGY
(LONGER term energy)
MUSCLES
________________
store glucose
as ________________
which can
glycogen
be broken down into glucose to
15-20 minutes
supply energy for_______________
of activity.
EXERCISE and ENERGY
(LONGER term energy)
After glycogen stores are
used up the body begins to
FAT
break down ________
That’s why aerobic exercise
must continue for longer than
20 minutes if you want to
lose weight!
Image from: http://blackmovie.us/movie/Fat.Albert/fat.albert.movie.jpg
ALL CELLS NEED ENERGY
Eukaryotes
All __________________
(including plant and animal cells) have
_______________
for cellular respiration
mitochondria
All __________________
(bacteria)
Prokaryotes
have their electron transport enzymes
attached to their
Cell membranes
_____________________
Remember: No membrane bound organelles!
Core High School Life Science
Performance Descriptors
High school students
performing at the
ADVANCED level:
analyze chemical reaction and chemical processes
involved in the Calvin Cycle and Krebs Cycle;
predict the function of a given structure;
High school students
performing at the
PROFICIENT level:
describe and give examples of chemical reactions
required to sustain life (…role of enzymes)
describe and give examples of chemical reactions
required to sustain life (hydrolysis, dehydration
synthesis, photosynthesis, cellular respiration, ADP/ATP,
role of enzymes);
describe the relationship between structure and function
High school students
performing at the
BASIC level
name chemical reactions required to sustain life
(… role of enzymes)
name chemical reactions required to sustain life
(hydrolysis, dehydration synthesis, photosynthesis,
cellular respiration, ADP/ATP, role of enzymes);
recognize that different structures perform different
functions;
Go Online
• Links from the authors on Creatine
• Share kimchi lab data
• Interactive test
• For links on cellular respiration, go to
www.SciLinks.org and enter the Web Code
as follows: cbn-3091.
• For links on the Krebs cycle, go to
www.SciLinks.org and enter the
Web Code as follows: cbn-3092.