Ch. 10 Flashcards
Photoautotrophs use energy to..
Assimilate small inorganic molecules
How do heterotrophs get their energy?
They take in organic molecules and respire them for energy
Photosynthesis is a complex process by which..
Carbon dioxide is converted to carbohydrate
Light is converted to chemical energy as it is captured by ___.
Plant pigments
Energy carriers transfer energy from pigments to ___
Endergonic reactions
Photosynthetic reactions produce ___
ATP
ADP can be phosphorylated to ATP by 3 methods:
- Photophosphorylation - photosynthesis; chloroplasts only
- substrate-level phosphorylation- respiration; cystol
- oxidative phosphorylation - respiration; mitochondria
CO2 is the ___ form of carbon
Carbohydrate is the ___ form of carbon
Oxidized; reduced
Oxidized
Not carrying as many electrons as it could
Reduced
Electrons are added to an atom
To convert CO2 to carbohydrates a plant needs both ___ and ___
Energy and reducing power
___ and ___ are oxidizing agents
NAD+ and NADP+
___ and ___ are strong reducing agents
NADH and NADPH
The tendency to accept or donate elections varies greatly and is known as a molecules..
Redox potential
Cytochromes are..
Intrinsic membrane proteins
Cytochromes contain a cofactor, ___, which holds an iron atom
Heme
Plastiquinones, like cytochromes, transport..
Electrons over short distances within a membrane
Plastocyanin is..
A small protein that carries electrons on a copper atom
Electron source is ___, and energy source is ___
Water; light
Light-dependent reactions create __ and ___
ATP and NADPH
____ is where ATP and NADPH interact with CO2 to produce carbohydrate
Stroma reactions
___ is one small segment of the electromagnetic radiation spectrum
Light
___ wavelengths have ___ energy
Short; high
___ are any material that absorbed certain wavelengths
Pigments
___ is the wavelengths of light a pigment absorbs
Absorption spectrum
___ absorbs red light and blue light very well
Chlorophyll-a
___ shows which wavelengths are most effective at powering a photochemical process
Action spectrum
___ are molecules that strongly absorb wavelengths not absorbed by chlorophyll-a.
Accessory pigments
The most common accessory pigments in land plants are ___ and the ___.
Chlorophyll-b and the carotenoids
Absorbed energy passes to chlorophyll-a via ___
Resonance
___ are poor and seem more important in absorbing excess light then protecting the chlorophylls
Carotenoids
Units with little chlorophyll-b are ___.
Photosystem I
Units where chlorophyll-b is present at levels almost equal to chlorophyll-a are ___
Photosystem II
____ receives electrons from another carrier, Q, which in turn receives electrons from phaeophytin
Plastoquinone
___ obtains another electron when a chlorophyll-a molecule absorbs light and is activated
Phaeophytin
Chemiosmotic phosphorylation generates the ___
ATP
Thylakoid lumen
Two regions of the thylakoid membrane: stroma lamella and grana
Photoautotrophs gather energy directly from ___
Light
