Please enable JavaScript.
Coggle requires JavaScript to display documents.
Chapter 10: Energy Metabolism (Photosynthesis), light dependent reactions…
Chapter 10: Energy Metabolism
(Photosynthesis)
Energy and Reducing Power
Reducing Power
Oxidation State: measure number of electrons added or removed from molecule during redox reaction
Reduced: electron added to an atom
Reduction Reaction: reduces the positive charge on an atom
Oxidation Reaction: increases the positive charge on an atom
Oxidized: an atom does not carry as many electrons as possible
Oxidized Compounds: often contain a lot of oxygen
Reduced Compounds: Contain Hydrogen
Redox Potential: tendency to accept or donate electrons
Oxidizing Agents: oxidize the material they react with
Reducing Power: force electrons onto compounds
Reducing Agents: an electron carrier w electrons
Other Electron Carriers
Plastoquiones: transport electrons over short distance within membrane
Plastocyanin: protein that carries electrons on metal atoms
Cytochromes: Small proteins that contain a cofactor, heme, holds metal atoms
Energy Carriers
Photosynthesis enters
Theories: energized pigments to endergonic reactions
allow one or several smaller intermediates
Easy control; smaller
ATP=intermediates
converted to ADP and phosphate by metabolic reactions
Created by ADP+Photosynthesis/Respiration
Three methods ADP phosphorylated ATP
Substrate-level phosphorylation
#
oxidative phosphorylation
#
occur in all part plant all times
Photophosphoryalation
#
light energy, photosynthesis
occurs only in chloroplasts in light
Guanosine Triphosphate
Enter pigment every reaction energy molecule
Large; difficult control
Photosynthesis
The Stroma Reactions
Calvin/Benson Cycle (C3 cycle)
convert carbon dioxide to carbohydrate
acceptor molecule react with carbon dioxide
two identical formed and contain 3 carbons (3 phosphoglycerate)
taken out of chloroplast
used to make fats, sugars, nucleic acids, amino acids
Anabolic Metabolism
The Synthesis of Polysaccharides
gluconeogenesis
dihydroxyacetone phosphate->fructose-1, 6-biphosphate->glucose-6phosphate
amylose and amylopectin
amylose- synthesize slowly
amylopectin- thousands of enzymes
3-phosphoglyceraldehyde
basis of all animal metabolism
rearranged in cytoplasm
"anabolism"
pathways of fats
storage forms of energy and carbon
pathways of polysaccharides
The Light-Dependent Reactions
Photosystem I
pair of chlorophylls called P700 bc absorb red light of 700 nm
Comes second, discovered first
Photosystem II
comes first
The Nature of Pigments
pigment
melanin
useful for attracting mates, hiding from predators
any material that absorbs wavelengths and therefore has distinctive color
Photosynthetic pigment
ideal would be black
Chlorophyll a absorbs only some red and some blue
#
fluorescence release of light by pigment
two most useful about photochemical process
action spectrum
which wavelengths are most effective at powering a photochemical process
absorption spectrum
graph that shows which wavelengths most strongly absorbed by a pigment
#
The Synthesis of ATP
chemiosmotic phosphorylation
The Nature of Light
Light is one small segment of the electromagnetic radiation spectrum
encompasses gamma rays, X-Rays, Ultraviolet light, infrared light, microwaves, radio waves, visible light
Radiation- physically particles quanta (quantum, singular), also called photons
short wavelengths
cosmic rays, gamma rays, and ultraviolet light
have large amount of energy in each quantum
Long wavelengths
have relatively little energy
infrared, microwave, radar, and radio waves
350-760nm, radiation animals see and plants use for photosynthesis
Environmental and Internal Factors
Water
greatly effect photosynthesis
C4
CAM
metabolic adaptations
Crassulacean Acid Metabolism
conserves water , permit photosynthesis
small amount carbon dioxide
first discovered in succulent leaves
Leaf Structure
temperate and tropical
above: palisade parenchyma
below: spongy mesophyll
excellent for absorb carbon dioxide
inefficient water for conserve
water loss reduced
small internal surface retard water vaper
low external surface w cylinder leaves
C4 metabolism
carbon dioxide conc. high and oxygen c. low
occur in Kranz anatomy leaves
Light
quantity
intensity/brightness
effected by several factors
weather
branch height
geographical location (equator)
rate-limiting factors
Light compensation point
due to technology of measuring, problem
duration
number of hours per day
12 hrs @ equator
longer toward each pole
quality
colors/wavelengths
#
sunlight contains 100 percent visible spectrum
blue light deflected upwards
