Homeworks - PP Exam 2 Flashcards
What is the correct order for the reactions of assimilation in nitrogen plants?
nitrate -> nitrite -> ammonium -> glutamine -> glutamate
What is the main form of nitrogen in the phloem of plants in a nitrogen-rich & light-lacking environment?
asparagine
What oxygen concentration can nitrogenase function in?
low oxygen concentration
What protein is synthesized in the root cells of a plant infected by Rhizobia?
leghemoglobin
“Plants can synthesize all 20 amino acids present in proteins”
True or False?
true
In plants, what are aromatic acids synthesized from?
phosphoenolpyruvate
What does glyphosate inhibit?
inhibits an enzyme in the shikimate pathway
What are nodulation factors produced by?
Rhizobia
How are nodulation factors synthesized?
they are synthesized in response to chemical signals secreted by the roots of legumes.
What does GOGAT stand for?
“Glutamine Oxoglutarate Aminotransferase”, but it is also known as ‘Glutamate synthase’, because it is involved in synthesizing glutamate from glutamine.
Where is GOGAT present?
present in plastids
What is GOGAT involved in?
involved in the synthesis of glutamate from glutamine.
What does a light-harvesting complex contain?
chlorophyll a, chlorophyll b, carotenoids, and proteins
What is the correct order of non-cyclic ETC on the thylakoid membrane?
water -> chlorophyll a in PSII (P680) -> plastoquinone -> cytochrome b6f -> plastocyanin -> chlorophyll b in PSI (P700) -> ferredoxin -> NADP+
What is the most DIRECT form of energy for ATP synthesis on thylakoid membrane?
pH gradient on thylakoid membrane (the sun is the main form but DIRECT is the pH gradient, it is ON the thylakoid membrane)
How many photosystems fo purple photosynthetic bacteria have?
one, and it’s similar to PSII
How many CO2 (carbon dioxide) molecules need to be fixed in the Calvin cycle to make a sucrose molecule?
12, (4 triosphosphates x 3 carbons each)
Why is photorespiration considered a wasteful process?
it doesn’t fix carbon dioxide and it consumes ATP
When are C3 plants more efficient than C4 plants?
in high concentration of carbon dioxide in the atmosphere
What type of plant reaches photosynthetic saturation at lower light intensity?
C3
What is the light compensation point?
when the amount of carbon dioxide fixed by plant equals the amount of carbon dioxide produced through respiration, 0 on the x-axis
Where is sucrose synthesized?
the cytosol/cytoplasm
Can sucrose be synthesized at night?
YES, from hexose-P by starch degradation
What is starch made of?
glucose molecules
Where is starch synthesized?
the chloroplast/plastids
Which of the following is not stored in the vacuole (malate, sucrose, starch, fructans)?
starch (stored in plastids)
Are phloem sieve elements live cells? What is different about them?
YES, they are modified to lack a lot of common organelles
