Photosynthesis Flashcards
C6H12O6 + 6 O2 —> 6 CO2 + 6H2O + energy
Which statement describes the results of this reaction?
C6H12O6 is oxidized and O2 is reduced
The oxygen consumed during cellular respiration is involved directly in which process or event?
Accepting electrons at the end of the electron transport chain (becomes water)
The free energy for the oxidation of glucose to CO2 and water is -686 kcal/mole and the free energy for the reduction of NAD+ to NADH is +53 kcal/mole. Why are only 2 molecules of NADH formed during glycolysis when it appears that as many as a dozen could be formed?
Most of the free energy available from the oxidation of glucose remains in pyruvate, one of the products of glycolysis
How many carbon atoms are fed into the citric acid cycle as a result of the oxidation of 1 molecule of pyruvate?
2 carbon atoms
In chemiosmotic phosphorylation, what is the most direct source of energy that is used to convert ADP + Pi to ATP?
Energy released from movement of protons through ATP synthase
Carbon dioxide is released during which of the following stages of cellular respiration?
Oxidation of pyruvate to acetyl CoA and the citric acid cycle
Which of the following produces the most ATP when glucose (C6H12O6) is completely oxidized to carbon dioxide and water?
Oxidative phosphorylation (chemiosmosis)
Approximately how many molecules of ATP are produced from the complete oxidation of 1 molecule of glucose (C6H12O6) in cellular respiration?
38 or 36
Which of the following most accurately describes what is happening along this chain? (Electron transport chain)
Each electron carrier alternates between being reduced and being oxidized
In the absence of oxygen, yeast cells can obtain energy by fermentation, resulting in the production of:
ATP, CO2, and ethanol (ethyl alcohol)
When oxygen is released as a result of photosynthesis, it is a by-product of which of the following?
Splitting the water molecules
What did Engelmann conclude about the congregation of bacteria in the red and blue areas?
Bacteria congregated in these areas because these areas had the most oxygen being released
An outcome of the Engelmann experiment was to help determine:
The relationship between wavelengths of light and the oxygen released during photosynthesis
Figure 10.1 shows the absorption spectrum for chlorophyll a and the action spectrum for photosynthesis. Why are they different?
Other pigments (antenna pigments) absorb light in addition to chlorophyll a
Which statement describes the functioning of photosystem II?
The electron vacancies in P680 are filled by electrons derived from water (splitting water)
Which of the following statements best represents the relationships between the light reactions and the calvin cycle?
The light reactions provide ATP and NADPH to the calvin cycle
Cycle returns ADP, Pi, and NADP+ to the light reactions
What is the primary function of the calvin cycle?
Synthesize simple sugars from carbon dioxide
The pH of the inner thylakoid space has been measured, as have the pH of the stroma and of the cytosol of a particular plant cell. Which relationship would you expect to find?
The pH within the thylakoid is less than that of the stroma
CAM plants keep stomata closed in daytime, thus reducing loss of water. They can do this because they:
Fix CO2 into organic acids during the night
Endergonic =
Anabolic
Exergonic =
Catabolic
Define hydrolysis
Adding water to break bond and extract energy
Exergonic is _______ energy
Extracting
Endergonic _______ and ______ energy
Requires and absorbs
Catabolic processes are almost always…
Hydrolysis reactions
Anabolic process are almost always…
Dehydration syntheses
The ______ the concentration of enzyme, the ______ the rate of reaction
Higher/higher, lower/lower
A pH change in an enzyme can prevent…
A polyphenol reaction
How would you change the salinity in an enzyme?
Adding ions
If hydrophobic/hydrophilic, structure might break
Define an acid
They liberate hydronium ions in aqueous solution
Donate a proton
How do enzyme speed up the rate of reaction?
Lowering the activation energy that is required to drive reaction
What does + delta G mean?
Spontaneous in the opposite direction