Chapter 10 Questions Flashcards
What are the reactants and products of photosynthesis?
6CO2 + 6H2O + Light energy —> C6H12O6 + 6O2
How does photosynthesis relate to cellular respiration? (see figure 9.2)
the net reaction for photosynthesis is essentially the reverse of the net reaction for cellular respiration
What cellular location does photosynthesis take place?
Leaves - chloroplasts
Which types of organisms undergo photosynthesis?
plants, algae, and some bacteria
Does photosynthesis rely on redox reactions? If so, what is being oxidized and what is being reduced in the overall equation for photosynthesis?
Yes
oxidation of H2O and the reduction of CO2
How does CO2 enter and O2 exit from plant leaves?
through microscopic pores called stomata
What are the two major locations inside chloroplasts?
Stroma and thylakoids
What are the two reactions that carry out photosynthesis?
Light Reactions and Calvin cycle
What is the wavelength range for visible light?
380-750 nm wavelengths
If chlorophyll appears green, which colors of the visible spectrum are being absorbed and which are being transmitted?
chlorophyll reflects and transmits green light
Which colors of the visible spectrum are mainly being used to fuel photosynthesis?
violet-blue and red light
Which colors of the visible spectrum are not being used for photosynthesis?
Green
What is the primary photosynthetic pigment in green plants?
chlorophyll a
What are the accessory pigments we talked about during class?
chlorophyll b and carotenoids
What is the purpose of having accessory pigments?
to broaden the amount of light that can be harnessed to fuel photosynthesis
Know how to read an absorption spectrum to determine which colors are being absorbed and which are being transmitted
An absorption spectrum is a graph plotting a pigment’s light absorption versus wavelength
How does the action spectrum for photosynthesis compare to the absorption spectrum for photosynthesis?
An action spectrum profiles the relative effectiveness of different wavelengths of radiation in driving a process (figure b)
What happens to the electrons in a solution of chlorophyll (i.e. chlorophyll that is outside of a cell) when they are excited by UV radiation?
When excited electrons fall back to the ground state, photons are given off, an afterglow called fluorescence
What happens to the electrons in chlorophyll that are found in intact plant cells once they become excited? (i.e. would chlorophyll molecules that are found in living cells fluorescence when exposed to UV radiation?)
If illuminated, an isolated solution of chlorophyll will fluoresce, giving off light and heat
Which specific location do light reactions take place?
in the thylakoids of chloroplasts
What are the requirements for light reactions?
Photosystems II and I H2O Light energy ADP and 3 Pi NADP+ NADP+ reductase
What are the products of light reactions?
O2
ATP
NADPH
What is the basic structure of photosystems?
consists of a reaction-center complex (a type of protein complex) surrounded by light-harvesting complexes
What are the two photosystems used during the light reactions?
Photosystem II
Photosystem I