1. What is respiration?
It is the process of breaking down (oxidation) of food to release energy.
Note: respiration may or may not need oxygen!
2. What is the type of energy released by respiration? What are their use?
(1) Chemical energy in form of ATP. ATP fuels all chemical reactions in the living body.
(2) Heat. Heat maintains body temperature. (Usually heat is in excess. So the organisms must release the excess heat.)
3. What is the chemical that is most frequently used as a respiratory substrate?
glucose
4. What is the role of ATP in metabolism?
As the carrier of energy to fuel chemical reactions inside the cell. Note that almost all reactions inside the body are chemical reactions.
5. What is phosphorylation?
The process of which ADP and phosphate(P) combines to form ATP.
6. What can ATP do?
What stated below are only examples. Almost all activities happening inside the living body requires ATP!
(1) active transport
(2) cell division
(3) muscle contraction
(4) synthesis of biomolecules
7. What are the two types of respiration?
(1) aerobic respiration
(2) anaerobic respiration
8. What are the location where respiration happens?
(1) cytoplasm (glycolysis and anaerobic respiration)
(2) mitochondria (Kreb cycle and oxidative phosphorylation in aerobic respiration)
9. What is the structures of mitochondria?
Outer membrane, inner membrane space, mitochondrial matrix, DNA.
10. What are the adaptive features of mitochondria? (require aerobic respiration)
(1) Highly folded inner membrane (provide a large surface area for more enzyme that are required in respiration to attach to.)
(2) There are enzymes required in respiration inside the mitochondrial matrix.
11. Which part of the cell contains enzymes that are required in respiration?
(1) cytoplasm
(2) inner membrane of mitochondria
(3) mitochondrial matrix
12. What are the three stages of aerobic respiration?
(1) glycolysis
(2) Kreb cycle
(3) oxidative phosphorylation
13. What are the two main stages of glycolysis?
(1) Breakdown of glucose into triose phosphate (ATP is comsumed).
(2) triose phosphate become pyruvate (ATP and NADH are produced).
14. In glycolysis, what is being given out from one molecule of glucose?
2 pyruvate
Net production of 2 ATP molecules
Net production of 2 NADH molecules
15. What molecule must be first converted to from triose phosphate before it enters the mitochondria to continue Kreb cycle?
Acetyl Coenzyme A
16. The Krebs cycle consists of two main chemicals, what are they?
4C compound
6C compound
17. What are the two major steps in the Krebs cycle?
(1) The combination of acetyl coenzyme A with 4 C compound (to form 6C compound).
(2) The regeneration of 4 C compound.
18. Which molecule is being released during the regeneration of 4C compound in the Krebs cycle?
(1) 2 carbon dioxide molecules
(2) 3 NADH
(3) 1 ATP
(4) 1 FADH
19. During the process of respiration, what are the three energy carriers? What is their comparative energy value?
Comparative energy value
NADH (~3ATP)
FAD (~2ATP)
ATP
20. Which energy carriers can be directly used in cells?
ATP
21. What is happening in oxidative phosphorylation?
NAD will be regenerated from NADH, releasing 3 ATP.
FAD will be regenerated from FADH, releasing 2 ATP.
NADH and FADH release H, which combines with oxygen and become water.
22. In the process of respiration, what is the final electron electron acceptor?
Oxygen
23. If there is no oxygen, which process will stop in aerobic respiration?
Oxidative phosphorylation
Krebs cycle
Note: If there is no process to accept the NADH and regenerate the NAD, glycolysis will also stop.
24. What substances can be used to test for the presence of NADH?
(1) hydrogen carbonate indicator
(2) lime water (turns milky is carbon dioxide is present)
25. What is the colour of hydrogen carbonate indicators at different concentration of carbon dioxide?
<0.03% purple
=0.03% (atmospheric carbon dioxide concentration)-red
>0.03% yellow
26. What is the meaning of alcoholic fermentation? What is the chemical formula?
The process of which glucose is turned into ethanol during anaerobic respiration.
Glucoseàpyruvateàethanol+carbon dioxide
During the process, the NADH produced in glycolysis will be used, and NAD will be regenerated from NADH so as to allow glycolysis to be continued.
27. What is the process of anaerobic respiration in skeletal muscle?
Glucoseàpyruvateàlactic acid (3C)
During the process, the NADH produced in glycolysis will be used, and NAD will be regenerated from NADH so as to allow glycolysis to be continued.
28. What is oxygen debt?
The extra amount of oxygen required to remove the lactic acid in the blood.
29. What is the industrial use for anaerobic respiration?
Alcoholic fermentation
(1) for making beer
(2) for making bread
Lactic acid fermentation
(1) for making yoghurt and cheese