Ap Bio Review Questions
Chapter 9 - Cellular Respiration
1. Define reduction & oxidation.
Reduction:the transfer of electrons between species in a chemical reaction, where there is a process of gaining electrons or a decrease in the oxidation state by an element
Oxidation:the process when an atom or an ion loses electrons
2. Where does glycolysis occur? Describe the process of glycolysis, include: reactant, products, energy investment phase & energy payoff phase.
-cytoplasm
-glucose is split into two molecules called pyruvate
-What comes out:
Pyruvate:2
Water:2
ATP:2 (2 ATP used and 4 produced)
NADH:2
H+:2
3. Does glycolysis need oxygen to occur?
-No
4. Describe the intermediate process that converts pyruvate to acetyl CoA
-You start with 2 pyruvate then lose one co2 which leaves the pyruvate molecules with 2 carbons instead of 3. Then NAD+ takes 2 hydrogens making NADH. The third thing that happens is the 2 carbon molecule attaches to coeznyme a and youre left with acetyl CoA
-the overall equation:
Pyruvate+CoA+NAD+ → Aceytl CoA+Co2+NADH
5. Describe the Citric Acid cycle.
-CAC Happens in the intermitochondrial matrix
-Net Products:
ATP:1
NADH:3 (4 including transition stage)
FADH2:1
6. Describe Oxidative Phosphorylation.
-happens on inner membrane
-passive transport-chemiosmosis
-active transport-ETC
-NADH and FADH2 transport electrons to the proteins giving the H+ ions enough energy to pass to the area of high concentration. This is because the electrons bounce through the proteins and release energy. (ETC)
-H+ ions diffuse down their concentration gradient through the enzyme ATP synthase because ATP synthase harnesses energy from the flow of protons to synthesize ATP from ADP and inorganic phosphate (chemiosmosis)
7. Where are the proteins of the ETC located?
-inner mitochondrial membrane
8. In cellular respiration, the energy for most ATP synthesis is supplied by what?
-etc and chemiosmosis
9. What is the primary role of oxygen in cellular respiration?
-acts as the end electron acceptor and create water
10. What is the pathway that electrons follow in a mitochondrion?
-etc —> citric acid cycle —> atp —> oxygen
11. Describe chemiosmosis.
-the movement of hydrogen ions across the membrane via ATP synthase. Chemiosmosis is recognized in the photosynthesis process in chloroplast and also in the cell membrane of prokaryotic cells that lack chloroplasts and mitochondria.
12. From one molecule of glucose, how many ATP are made from glycolysis?
Citric Acid Cycle? Oxidative phosphorylation?
-2, 2, 32-34
13. What is fermentation?
-Fermentation is a type of redox metabolism carried out in the absence of oxygen. During fermentation, organic molecules are catabolized and donate electrons to other organic molecules. In the process, ATP and organic end products are formed. Because oxygen is not required, it is an alternative to aerobic respiration.
14. Differentiate between lactic acid fermentation & alcohol fermentation.
-Alcoholic fermentation produces ethanol, carbon dioxide, and NAD+. Lactic acid fermentation produces lactic acid (lactate) and NAD+
15. Why is glycolysis considered to be one of the first metabolic pathways to
have evolved?
-Glycolysis is the first pathway used in the breakdown of glucose to extract energy. It takes place in the cytoplasm of both prokaryotic and eukaryotic cells. It was probably one of the earliest metabolic pathways to evolve since it is used by nearly all of the organisms on earth
16. What are the two energy-carrying molecules?
NADH and FADH+
17. What is the equation for cellular respiration
C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy
Ch.10 - Photosynthesis
1. What are the products of the light reaction?
-ATP, NADPH, O2
2. Differentiate between PSII and PSI.
-PS2 functions first and is best at absorbing the wavelength of 680nm whereas PS1 is second and is best at absorbing the wavelength of 700nm
3. Differentiate between linear and cyclic electron flow.
-Linear electron flow creates ATP and NADPH and uses both photosystems whereas cyclic electron flow only makes ATP and only uses PS11
4. Where is the ATP Synthase located in the chloroplast?
-thylakoid membrane
5. Where does the Calvin cycle take place?
-Stroma
6. Describe & draw the Calvin cycle
7. What is the flow of electrons in photosynthesis?
Light Absorption → Water Splitting → ETC → Proton Pumping → ATP and NADPH Formation
8. What is the equation of photosynthesis:
6 CO2+ 6 H2O+ Light Energy → C6H12O6 + 6 O2
Comparison of Photosynthesis & Cellular Respiration-
1. Compare Chemiosmosis in the mitochondria to the chloroplast.
1. Location of Proton Gradient:
- In chloroplasts, the proton gradient is created across the thylakoid membrane, with protons being pumped into the thylakoid lumen during the light-dependent reactions.
- In mitochondria, the proton gradient is established across the inner mitochondrial membrane, with protons being pumped into the intermembrane space during the electron transport chain.
2. Source of Energy:
- In chloroplasts, the energy to pump protons comes from light energy absorbed by chlorophyll during photosynthesis.
- In mitochondria, the energy comes from the oxidation of nutrients, such as glucose, during cellular respiration.
3. Final Electron Acceptors:
- In chloroplasts, the final electron acceptor is NADP+, which is reduced to NADPH.
- In mitochondria, the final electron acceptor is oxygen, which combines with electrons and protons to form water.
2. Compare the overall equations of photosynthesis to cellular respiration.
-Theyre the opposite
3. Compare the structure of the mitochondria to the chloroplast.