Photosynthesis
Photosynthesis 2
This one is random
DNA replication
DNA replication 2
100
Where does photosynthesis occur?
Where do light reactions occur? Calvin cycle?
Photosynthesis occurs in the chloroplast of plant cells
Light reactions occur in the thylakoid membrane
Calvin cycle occurs in the stroma
100
Given the equation for photosynthesis:
6CO2 + 6H2O -> C6H12O6 + 6O2
What is the oxidation step? Reduction?
Which happens in the light reactions, and which happens in the Calvin cycle?
Oxidation: H2O->O2 ; Happens in the light reactions
Reduction: CO2->C6H12O6 ; Happens in the calvin cycle
100
How many DNA strands are used as templates in DNA replication?
2
100
When adding new nucleotides to a pre-existing strand, where would they be added?
The 3' end (ribose sugar end)
100
What are pieces of the lagging strand called?
Okazaki fragments
200
What is a photosystem?
A collection of pigments in the chloroplast that absorb photons
200
Given the equation for photosynthesis:
6CO2 + 6H2O -> C6H12O6 + 6O2
What is the oxidation step? Reduction?
Which happens in the light reactions, and which happens in the Calvin cycle?
6H2O->6O2 is oxidation, it happens first in the light reactions
6CO2 -> C6H12O6 is reduction and happens second in the Calvin Cycle
200
What does it mean for DNA replication to be "semi-conservative"?
Each new DNA molecule contains one daughter strand and one parental strand
200
The enzyme DNA polymerase III would add DNA nucleotides to the ___ end of the lagging strand and ___ end of the leading strand
3', 3'
200
What is the leading strand? What is the lagging strand?
How are each created?
-Leading strand: continuous strand, synthesizes the same direction as helicase moves
-Lagging strand: synthesizes the opposite direction helicase moves
300
There is a conversion of energy observed in photosynthesis.
____ energy is converted to ____ energy
Electromagnetic energy into chemical potential energy
300
What is made in the light reactions that is then used in the calvin cycle?
ATP and NADPH
300
In the chloroplast, there are molecules called pigments that absorb solar energy.
What are the 2 main pigments and what light colors do they reflect?
Chlorophylls: reflect green and yellow
Carotenoids: reflect yellow, orange, and red
300
What enzymes are involved with the formation of the replication bubble? What does each one do?
-Topoisomerase: break and rejoin single stranded DNA to relieve some tension of twisting
-Helicase: opens and unwinds double helix
-Single stranded binding proteins (SSBPs): stabilize single stranded DNA after strands have been separated
300
What enzymes are involved with the formation of the new daughter strand? What does each one do?
-Primase: Adds RNA primer at beginning of strand
-DNA polymerase III: adds DNA nucleotides on the 3' end to create new strands
-DNA polymerase I: removes RNA primer and replaces it with DNA nucleotides
-Ligase: Joins fragments of lagging strand into a continuous strand
400
What section of the electromagnetic spectrum are plant pigment molecules able to absorb?
Visible light, 400-700 nm
400
What is the primary function of light reactions? Calvin cycle?
Hint: think of the equation for photosynthesis and the REDOX reactions
Light reactions: oxidize water into O2 (oxygen)
Calvin cycle: Reduce CO2 into glucose (a simple sugar)
400
In the light reactions, there are collections of pigments called photosystems.
What are the names of these photosystems and what is the product made by each?
Photosystem 2: makes ATP via the electron transport chain and ATP synthase
Photosystem 1: makes NADPH by giving electrons to NADP+
400
Put these events in order:
1) RNA primer is added
2) DNA nucleotides are added by DNA polymerase III
3) RNA primer is removed by DNA polymerase I
4) Fragments are joined into a continuous strand by ligase
5) Helicase unwinds the double helix
5, 1, 2, 3, 4
400
If a mutation caused the enzyme primase to be nonfunctional, what would happen?
No new strands would be synthesized
500
When photons are absorbed by a photosystem, electrons enter an excited state by gaining energy.
Explain what 3 things can happen after the electron enters this excited state.
1) Resonance: Energy is transferred to a nearby pigment molecule
2) REDOX reaction: the electron is transferred to an electron carrier
3) Fluorescence: Light or heat is produced and the electron goes back to its original energy state
500
What are the 3 phases of the Calvin Cycle? Describe what happens in each.
1) Fixation: CO2 is incorporated and reacts with RuBP to make 3PGA
2) Reduction: 3PGA is used to make G3P using ATP and NADPH
3) Regeneration: G3P is used to regenerate RuBP
500
ATP synthase is an enzyme in membranes that is used to synthesize ATP using the energy from an electrochemical gradient.
Where in a plant cell would you expect to find ATP synthase?
Thylakoid membrane and the inner membrane of the chloroplast.
500
On this diagram, where would the leading strand be and in what direction would it be synthesized (towards or away from replication fork)?
Top strand, moving towards the replication fork
500
On this picture, where would the 5' and 3' end be of each parental strand?
Hint: looking at the leading and lagging strands
Top strand: left side 5'; right side 3'