Bio 21 Cell Biology

List of Terms and Study Guide 3

for MiniExam 2 on 3/7

 

Princliples of Bioenergetics

1st Law of Thermodynamics

2nd Law of Thermodynamics

entropy

enthalpy

catabolic reactions

anabolic reactions

oxidation

reduction

free energy change

standard free energy change

exergonic

endergonic

exothermic

endothermic

 

Coupled reactions and Biosynthesis

coupled reactions

overall free energy change

net standard free energy change

activated carrier molecules

ATP

GTP

NADH

FADH2

NADPH

Acetyl CoA

Cell Metabolism

3 stages of cell metabolism in breakdown of food molecules

macromolecules --> subunits

outside cell --> cytosol

subunits --> acetyl CoA

cytosol (--> mitochondria)

complete oxidation

acetyl CoA --> CO2 and H2O

 

Glycolysis and Fermentation

glycolysis

anaerobic

(1) glucose --> (2) glyceradehyde 3-phosphate --> (2) pyruvate

-2ATPs + 4 ATPs = 2 ATPs net

substrate-level phosphorylation

2 NADH

fermentation

NADH --> NAD+

anaerobic

lactate

ethanol + CO2

 

Citric Acid Cycle

Krebs cycle/tricarboxylic acid cycle

mitochondrial matrix

oxidation of pyruvate

oxaloacetate

citrate

decarboxylation

major end products

CO2 and NADH

each turn of cycle: 3 NADH, 1 FADH2, 1 GTP (-->ATP)

one glucose => 2 pyruvate => 2 acetyl CoA

condensation rxns

oxidation vs reduction

 

Oxidative phosphorylation

electron transport chain

NAD+

electron acceptor

oxidizing agent

NADH

electron donor

reducing agent

redox rxns

mitochondrial inner membrane

cristae

plasma membrane of aerobic bacteria

prosthetic groups

ubiquinone

cytochromes

2 NADH + 2 H+ + 1 O2 --> 2 H2O + 2 NAD+

FADH2

chemiosmotic coupling

ATP synthase

H+ pump

H+ gradient

proton-motive force

10 H+ pumped per NADH molecule oxidized

3 H+ per ATP

1 H+ for ATP transport

 

You should be able to:

1. Explain, in your own words, the First and Second Law of Thermodynamics.

2. Distinguish between exergonic and endergonic reactions.

3. Describe the difference between free energy change (G) and standard free energy change (Go'), and how the ratio of reactants to products contributes to G. Be able to calculate G and determine whether or not an overall reaction will proceed spontaneously (given the appropriate data; e.g. G values for individual steps in a coupled reaction.)

4. Describe the function of ATP in the cell.

5. Describe the overall summary equation for cellular respiration.

6. Distinguish between substrate-level phosphorylation and oxidative phosphorylation.

7. Explain how exergonic oxidation of glucose is coupled to endergonic synthesis of ATP.

8. Define oxidation and reduction.

10. Explain how redox reactions are involved in energy exchanges.

11. Describe the role of ATP in coupled reactions.

12. Explain why ATP is required for the preparatory steps of glycolysis.

13. Write a summary equation for glycolysis and describe where it occurs in the cell.

14. Describe where pyruvate is oxidized to acetyl CoA, what molecules are produced and how it links glycolysis to the citric acid cycle.

15. Recognize the steps of the citric acid cycle and be able to describe what is happening in terms of "molecules in" and "molecules out".

16. Explain how the exergonic "fall" of electrons down the electron transport chain is coupled to the endergonic production of ATP by chemiosmosis.

17. Describe the process of chemiosmosis.

18. Explain how membrane structure is related to membrane function in chemiosmosis.

19. Summarize the net ATP yield from the oxidation of a glucose molecule by constructing an ATP ledger which includes electron carrier production (i.e., NADH, FADH2) during the different stages of glycolysis and cellular respiration.

20. Describe the fate of pyruvate in the absence of oxygen.

21. Explain why fermentation is necessary.

22. Distinguish between aerobic and anaerobic metabolism.

23. Describe evidence that the first prokaryotes produced ATP by glycolysis.