Shared Flashcard Set

Details

Botany metabolism
metabolism
67
Biology
Undergraduate 2
10/18/2006

Additional Biology Flashcards

 


 

Cards

Term
what is the generalized equation for photosynthesis?
Definition

6CO2 + 6H2O + light E = C6H12O6 + O2

Term
What is the disaccharide used for carb. transport in plants? what are the 2 sugars?
Definition
sucrose = glucose + fructose
Term
what vessels transport water in plants?
Definition
xylem
Term
what is the driving force for water movement? what causes it?
Definition
evapotranspiration
evaporation of H2O through stomates
Term
what is attraction between like molecules called?
Definition
cohesion
Term
which vessel is under tension? which under pressure?
Definition
xylem - tension
phloem - pressure
Term
name two carotenoids and colors associated with each
Definition
carotenes - yellow, orange, red
xanthophyll - pale yellow
Term
what is a bioassay?
Definition
use of living organisms to test for (detect and/or quantify) the presence/amount of a chemical
Term
what did Engleman's experiment with a prism and Spirogyra determine?
Definition
absorption peaks of chlorphylls coincide with action spectrum of photosynthesis. showed that chlorphyll plays a role in photosynthesis.
Term
what happens when isolated chlorphyll absorbs light? what happens to light absorbed by chlorophyll in membranes?
Definition
it fluoresces - gives off heat and red light
Energy trapped in chemical bonds
Term
what are the two reactions of photosynthesis? where do they take place?
Definition
1. Light reactions/light dependent reactions - thylakoid membrane
2. Calvin cycle/light independent reactions - stroma
Term
what are the products of the light dependent reactions?
Definition
ATP, NADPH, O2
Term
what does NADPH stand for?
Definition
nicotinamide adenine dinucleotide phosphate
Term
what are the inputs of the calvin cycle?
what is the product?
what is the substrate?
Definition
1. Energy from the light dep. rxtns. (ATP, NADPH) and Carbon from CO2
2. product = glucose
3. substrate = ribulose biphosphate (RuBP)
Term
what are stacks of thylakoids called?
Definition
granum
Term
what is the absorption peak for photosystem 1? photosystem II?
Definition
I - 700nm
II - 680nm
Term
How many turns of the calvin cycle does it take to get one glucose molecule?
Definition
six
Term
what fills the electron 'hole' in photosystem I? photosystem II?
Definition
ps1 electrons come from ps2
ps2 electrons come from oxygen evolving complex
Term
what is photolysis? what are the products of the Oxygen evolving complex?
Definition
1. splitting of H2O in presence of light
2. O2, H+, electrons
Term
what is the differece between noncyclic and cyclic photorespiration? what is the differene in products?
Definition
1. noncyclic - electrons travel from OEC to ps2 to Redox rxtns. to ps1 and become NADPH
O2, ATP, NADPH produced
2. cyclic - electrons travel from ps1 to Redox rxtns. and back to ps1.
products - ATP
Term
what are the two sources of H+ inside thylakoid?
Definition
1. H+ pulled across by Redox transport
2. H+ produced from oxygen evolution
Term
where do hydrogen ions pass from inside of thylakoid to outside? what product is formed and what is the process called?
Definition
ATP synthase (Coupling factor)
ATP formed for every 2 H+
Chemiosmosis
Term
what 3 carbon molecule is formed when RuBP combines with CO2 in the Calvin cycle? what 3C molecule is sent to glycolysis?
Definition
1. phosphoglyceric acid
2. glyceraldehyde 3-phosphate
Term
what are the three possible substrates of Rubisco?
Definition
Ribulose BiPhosphate (RuBP), oxygen, CO2
Term
what two types of respiration do plants perform? which one occurs only in the light and requires oxygen?
Definition
photorespiration (light only, O2) and aerobic respiration (day and night)
Term
what enzyme is partially coded by both chloroplast and nuclear dna? what activates this enzyme?
Definition
Rubisco, activated by light
Term
what type of respiration results in CO2 formation?
Definition
BOTH aerobic resp. and photoresp.
Term
what are the disadvantages of photorespiration?
Definition
1. no ATP production
2. Rubisco is occupied, less for carbon fixation (CO2)
Term
what is the percentage of oxygen in the air? what is the percetage CO2?
Definition
O2 - 20-21%
CO2 - 0.035%
Term
explain the additional pathway available to C4 plants for fixing CO2? what enzyme responsible?
Definition
PEP(3C) + CO2 = oxaloacetic acid (4C)
enzyme - PEP carboxylase
Term
what is typical C4 plant environment? what are some common C4 plants?
Definition
1. tropical/subtropical
2. corn, sorgum, sugar cane, crabgrass, pigweed
Term
what are the four characteristics of Kranz anatomy in C4 plants?
Definition
1. enlarged bundle sheath cells
2. stomates on top and bottom of leaves
3. uniform mesophyll - no distinction between palisades and spongy mesophyll
Term
where is each carbon fixing enzyme found in C4 plants?
Definition
Rubisco in bundle sheath cells
PEP carboxylase in mesophyll
Term
explain the path of CO2 to get to calvin cycle in C4 cells?
Definition
1. atmospheric CO2 trapped by PEP carboxylase
2. PEP(3C) converted to oxaloacetic acid(4C)
3. OAA converted to malic acid(4C)
4. Malic acid coverted to pyruvic acid(3C) + CO2 5. Rubisco traps CO2, enters Calvin cycle
Term
What is the main advantage of the Kranz anatomy?
Definition
By being sequestered in bundle sheath cells, Rubisco is not exposed to O2 so isn't wasted on photorespiration. Gets pure CO2 from malic acid-pyruvic acid conversion
Term
where does calvin cylce occur in C4 plants? where do the light dependent reactions take place?
Definition
1. Calvin cycle - chloroplasts of bundle sheath cells
2. Light dep.rxtns. - chloroplasts of mesophyll
Term
where would you find starch in C3 plants? C4? why?
Definition
C3 - mesophyll
C4 - bundle sheath
why?- starch associated with calvin cycle
Term
what is the major disadvantage of C4 pathway?
Definition
requires extra energy input
Term
what adaptation allows C4 plants to do well in hot climates?
Definition
able to partially close stomates, allowing H2O conservation but still allowing CO2 input.
Term
what does CAM stand for? what common families use this pathway?
Definition
Crassulacean Acid Metabolism
Crassulaceae (jade, mother of thousands)
Cactaceae (cacti)
Bromeliacieae (bromeliads, pineapple)
Term
what is the CAM strategy?
Definition
Stomates open at night.
CO2 fixed at night by PEP carboxylase
CO2 stored as malic acid(4C) in vacuoles
CO2 released to Rubisco during the day
Because stomates closed during the day, Rubisco not exposed to O2 (no photorespiration)
Term
which hormone affects tropisms?
Definition
auxin
Term
what kind of hormone is indoleacetic acid?
Definition
auxin
Term
where is IAA produced?
Definition
apical meristems and young, developing leaves
Term
which hormone inhibits lateral bud growth?
Definition
auxin
Term
which hormone inhibits root growth?
Definition
auxin
Term
which hormone promotes root initiation?
Definition
auxin
Term
what two hormones involved in 2,4 D and 2,4,5 T herbicides?
Definition
auxin + ethylene
Term
what hormone triggers fruit development and flowering?
Definition
auxin, gibberellins
Term
what hormone inhibits fruit and leaf abscission?
Definition
auxin
Term
which hormone will cause root initiation in tissue culture?
Definition
auxin
Term
which hormone causes shoot initiation in tissue culture?
Definition
cytokinen
Term
what hormone exhibits polar transport?
Definition
auxin
Term
what hormone will break dormancy of seeds and buds?
Definition
gibberellins
Term
which hormone promotes fruit formation and development but with parthenocarpic fruits?
Definition
gebberellins
Term
what hormones promote cell division?
Definition
auxin, cytokinen
Term
what hormone produced in roots?
Definition
cytokinens
Term
what hormone promotes growth of lateral buds?
Definition
cytokinens
Term
what hormone promotes leaf abscission?
Definition
ethylene
Term
what hormone can both promote and inhibit flowering depending on species?
Definition
ethylene
Term
what hormone promotes leaf and flower aging?
Definition
ethylene
Term
what hormone causes epinasty?
Definition
ethylene
Term
what hormone causes root and stem thickening?
Definition
ethylene
Term
what hormone causes buds to become dormant?
Definition
abscisic acid (ABA)
Term
what hormone causes stomates to close?
Definition
abscisic acid (ABA)
Term
what hormone promotes the growht of bud scales?
Definition
abscisic acid (ABA)
Term
what hormone sometimes called dormin?
Definition
abscisic acid
Supporting users have an ad free experience!