Textbook learning: Mann & Lazier, Miller Flashcards
Brownian motion
Particles undergo random walk. Is one mechanism causing aggregation of particles.
Effect of turbulence on predator and prey interactions?
Increases rate of interaction between predator and prey
Gross versus net primary production?
Gross PP is total; net is total minus respiration. Net production is available to herbivores
Total carbon dioxide in all three forms in oceanic water? per liter
90 mg CO2 l-1
dominant pigments in phytoplankton
chlorphyll a. but chlorophylls b, c, and d plus accessory pigments (carotenes, xanthophylls, phycobilins) are also present. Note: accessory pigments often dominate over the green color of chlorophyll, resulting in brown, golden, or red
accessory pigments to chlorophyll used in photosynthesis
carotenes, xanthophylls, phycobilins
wavelength within which all photosynthetically active pigments absorb light
400-700 nm (PAR)
maximum absorption of chl.a occurs in which wavelengths (and color) ranges?
red (650-700 nm), and
blue-violet (450 nm)
light reactions - photosynthesis
pigments abosrb light
electron inthe pigments acquire a higher E level
e from electrons tranfered to rxns in which ADP is changed to ATP, forming NADPH2
dark reactions - photosynthesis
reduction of CO2 by NADPH2
requires ATP to prod the end prod of high E carbonhydrates - usaully polysaccharides - and org cmpound eg lipids
reduction of NO3 yeilds amino acids and proteins
calculation to measure primary prod using 14C incubation
and units
rate of prod = ((Rl-RD) * W)
(R x t)
units= new C mg fixed per m-3 per h-1
R = total radioactivity t = hrs RL is radioactive ount inthe "light" Rd is radioactive count in the "dark" W = weight of all forms of CO2 in the sample, mg C m-3 determined independently
Percentage breakdown of DIC allotment
And take home point
H2CO3: 1%
CO3: 10%
HCO3: 90%
ref: class notes (note - this is approximate, hence the 101%) take home point: RuBP requires CO2; hence CO2 can actually be limiting! Hence CCMs!
Average [CO2] in oceanic waters:
Total DIC and CO2
DIC: 2.3 mM
CO2: 20 µM
[H2CO3] aqueous CO2 concetration in seawater
CO2: 20 µM
[DIC]total in seawater
2.3 mM
Essential function of the CCM
speeds up equilibrium reaction:
CO2 HCO3
Maybe: photorespiration? BUT, possibly, photorespi could protect vs light-inflected damage to the cell.... (ref: class notes, p 17)
Intermediate products of dark reaction are photolabile, break down under intense light, and cannot be returned to the photosynthetic pathway. Incr of this process decreases overall rate of photosynth.
Michelis Mentin kinetics
V = (Vmax * S) / (Ks + S)
Ks = substrate quantity at which rate = 50% of max...? S = substrate
Observations on Michelis Mentin curve
1) more substrate = higher rate initially
2) then, flattens out at Vmax
rate of prod = ((Rl-RD) * W)
(R x t)
reaction that describes new C acquisition i.e. primary productivity! 14C incubations…
imagine the curve of the response of photosynthesis (P) to changes in light intensity. What is the point called where respiration (R) balances the amount of photosynthesis?
compensation point (occurs at "I sub c", Ic, light intensity)
compensation point (photosynthesis)
in the curve of the response of photosynthesis (P) to changes in light intensity. What is the point called where respiration (R) balances the amount of photosynthesis
average amount of light in the euphotic zone
ID = (I0/kD) x (1-e^-kD)
where I0 is surface radiation
k is extinction (of light) coefficient
D = depth over which the light is averaged
p 52 Miller text
Equation describing how the E of protons varies with pigments!
E = hc/v
Red = shorter wv
and higher E
Longer wavelengths have less E
