Download Lecture 14: Study guide

Biology 102, Lecture 14 Study Guide
February 13, 2004
TOPIC: Cellular respiration (Glucose metabolism)
I.
Glucose metabolism (overview)
A. The formula
B. Major steps
C. Location of different reactions
D. Why focus on glucose?
II. Glycolysis: the first step in capturing energy in glucose
A. Two key steps
B. Net results (what is produced?)
C. What happens to the pyruvate formed in glycolysis
III. Cellular respiration: How additional energy is captured from glucose
A. The net result
B. Details
1. Transition from glycolysis to Kreb’s cycle
2. Kreb’s cycle
3. Electron transport system
Study questions
1.
Glycolysis is an exergonic (energy-releasing) pathway. Why is ATP required at the
beginning?
2.
Where in the cell does glycolysis take place?
3.
Briefly explain how you can get fat from eating carbohydrates.
4.
Name the two steps of glycolysis, and describe what happens in each step.
5.
During glycolysis, describe what happens with respect to:
a.
The six carbon chain of glucose

In which molecules do the carbons end up, and how many carbons are in that
molecule
b.
Electrons and protons stripped off during the reactions

Where are they at the end of glycolysis? (Associated with which molecules?)
c.
Energy released during the reaction.
6.
Is there net loss or gain of ATP during glycolysis?
7.
Is oxygen required for glycolysis?
8.
What happens to the pyruvate molecule formed in glycolysis
a.
In the absence of oxygen?
b.
In the presence of oxygen?
ADDITIONAL QUESTIONS ON REVERSE SIDE!
9.
What happens to the electrons and H+ carried by NADH and NADH2
a.
In the absence of oxygen?
b.
In the presence of oxygen?
10.
During which stages of cellular respiration is CO2 produced?
11.
During the Kreb’s cycle, what happens with respect to:
a.
ATP (formed or used?)
b.
C-C bonds (made, or split?)
c.
CO2 (consumed or produced?)
d.
Electrons and protons (added to carbon chain, or stripped off?)
e.
NADH and FADH2 (formed or broken down? Explain in conjunction with
electron/proton fate. You should also know the chemical formula for these carrier
molecules both with and without their associated electrons and protons.)
12.
Where does the Krebs cycle take place? Be as specific as possible.
13.
Where is the electron transport chain located? Be as specific as possible.
14.
Where does the energy come from to generate ATP in the electron transport chain?
a.
What molecules carry the electrons/energy to the chain?
b.
How is the electron transport chain linked to the production of ATP (HINT: Explain
role of H+ )
15.
During which stage of glucose metabolism (glycolysis, Kreb’s cycle, electron transport
chain) is most of the ATP generated?
16.
What is the ultimate fate (for cellular respiration) of the electrons and protons carried
temporarily by NADH and FADH2?
17.
How is oxygen utilized during cellular respiration (HINT: Very related to previous
question.)
18.
Make as many comparisons as you can between photosynthesis and cellular respiration.
Think about chemical formulas, role of electrons and electron carriers, method by which
ATP is produced, etc...
19.
Compare what happens during the Krebs cycle to what happens during the Calvin-Benson
cycle in photosynthesis, in terms of the key items in question 11.
a.
ATP (formed or used?)
b.
C-C bonds (made, or split?)
c.
CO2 (consumed or produced?)
d.
Electrons and protons (added to carbon chain, or stripped off?)
ADDITIONAL QUESTIONS ON REVERSE SIDE!
e.
NADH, NADPH, FADH2 (formed or broken down? Explain in conjunction with
electron/proton fate. You should also know the chemical formula for these carrier
molecules both with and without their associated electrons and protons.)
ADDITIONAL QUESTIONS ON REVERSE SIDE!