Chapter 8, Photosynthesis Flashcards
Photosynthesis is the conversion of ______ energy to _______ energy
light, chemical
Heterotrophs
organisms which cannot make own food from simple carbon compounds
Autotrophs
organisms which can make own food from simple carbon compounds
Parts/Structures of Photosynthesis
- Plants parts
- basic reactants and products
- light
- pigments
- photosystems
Reactants of photosynthesis
carbon dioxide, water, light (energy)
Products of photosynthesis
Food (carbohydrates), oxygen
Formula for photosynthesis
H2O+CO2–> C6H12O6 + O2
Water diffuses into plant through _____, travels up stem to the leaves, through the ______ in the vascular bundles
roots, Xylem
CO2 enters plants through microscopic pores called
stomata
Stomata located
on underside of leaves
Carbon dioxide and water enters plants through
diffusion
Light comes in particles termed _______
photons
Light also travels in ______
waves
Wavelength is
the distance from one wave peak to the next
Electromagnetic Radiation is
all forms of radiant energy, including visible light
Relationship between wavelength and energy is
inverse
the _______ wavelengths have _____ energy
longer, less shorter, more
Visible light spectrum ranges from
400-700 nm
White light composed of…
all the visible light, all colors
Pigments are
molecules that can absorb some wavelength but nor others
How to pigments how color
Wavelength that are not absorbed are reflected (transmitted) so they can be seen
An action spectrum is
a graph for entire plant, plotting photosynthetic activity (action) vs wavelength
One can determine which of many pigments in a plant are the major ones for photosynthesis by
comparing absorption spectrum of each pigment with action spectrum
Plant does __________ with the light absorbed
photosynthesis
Chlorophyll is hydro________
hydrophobic
___________ tail insert chlorophyll into the __________ membrane
hydrocarbon, thylakoid
The head of chlorophyll has alternating ______ and _____ bonds
double, single
These double and single bonds useful for
picking up and giving off extra electrons
Chlorophyll a and b only differ in
one functional group
There is a _____ group in chlorophyll a, and a _______ group in chlorophyll b
Carboxyl (COH) in a, and a Methyl (CH3) in b
Photosystems are
clusters of pigments
Photosystems contain the pigments
chlorophyll a and b, and some xanthophyll and carotene
Photosystems can have ____-____ pigments
250-400
Photosystems arranged so that light energy is passed from pigments that absorb ____ wavelength to those that absorb ______ wavelengths
shorter to longer
There is a special pair of Chlorophyll ___ molecules the ultimately…
chlorophyll A, receive the energy/electrons from all other pigments, pass the actual electrons not just energy
Photosystem I, chlorophyll a is _____
P700
Photosystem II, chlorophyll a is ____
P680
The numbers P700/P680 refers to
optimal absorption
Chlorophyll a in Photosystems 1 and 2 pass high energy electrons to…
molecules outside the photosystem
2 types of photosynthetic reactions
- energy-transduction reaction
- carbon-fixation reactions
Energy transduction reactions are also called…..and they are involved with…
light reactions/light dependent reactions
energy transfer
carbon fixed reaction are also called…involved with…
dark reactions/light independent reactions
CO2 fixed, enzymatically combined with, covalently bonded to RuBP
Photolysis is when
water molecules get split, produces 2 electrons, 2H+, and 1/2 H2O
Step 1 on light dependent reaction
noncyclic Photophosphorylation
energy/electron transfer –> NADPH
Step 2 in light dependent reaction
Photolysis
splitting water
Step 3 in light dependent reaction
chemiosmosis
making ATP
Step 4 in light dependent reaction
Cyclic Photophosphorylation
energy/electron transfer
**study steps in photosystem 1
