Biology
Photosynthesis in Plants
1,492 Questions
Photosynthesis is the biological process by which plants convert light energy into chemical energy. This page contains practice questions covering essential topics like chlorophyll, light reactions, and the pathways specific to plants. This material is crucial for medical entrance exams and academic assessments.
Chlorophyll and pigmentsLight reactionsCalvin cycleCAM plantsElectron transportPhotosynthesis factors
Photosynthesis in Plants Questions
-
Strobilus
-
Calyptra
-
Cotyledons
-
Integuments
-
Locules
C
Correct answer
Explanation
Two large green hemispherical structures which enclose the embryonic axis are called as the cotyledons. The cotyledons may be one or two in number depending on the type of plant. The cotyledons are important becausetheyt give nutrients during the early development of the plant before starting the process of photosynthesis.
-
phycourobilin
-
phycoerythrobilin
-
phycoerythrin
-
phycocyanobilin
-
phycocyanin
D
Correct answer
Explanation
Phycocyanobilin is a blue phycobilin, i.e. a tetrapyrrole chromophore found in cyanobacteria and in the chloroplasts of red algae, glaucophytes and some cryptomonads. Phycocyanobilin is present only in the phycobiliproteins allophycocyanin and phycocyanin, of which it is the terminal acceptor of energy.
-
Chlorophyll b
-
Chlorophyll a
-
Pheophytin
-
Carotenes
-
Xanthophylls
C
Correct answer
Explanation
Pheophytin is a chemical compound that serves as the first electron carrier intermediate in the electron transfer pathway of photosystem II (PS II) in plants and the photosynthetic reaction center (RC P870) found in purple bacteria.
B
Correct answer
Explanation
Plants absorve carbon dioxide from atmosphere.
-
Emerson and Arnold - Existence of light and dark reactions in photosynthesis
-
Engelmann - Chloroplasts as the site of photosynthesis
-
Hatch and Slack - C3 pathway for CO2 fixation
-
Ruben and Kamen - Oxygen comes from water in photosynthesis
-
Peter Mitchell - Chemiosmotic hypothesis of ATP synthesis in light reaction
C
Correct answer
Explanation
In 1966, Hatch and Slack reported the C4 pathway for CO2 fixation in certain tropical plants.
In 1954, Melvin Calvin traced the path of carbon in photosynthesis and gave the C3 cycle (now known as Calvin cycle).
-
Both P and Q
-
Both P and S
-
Both Q and R
-
Both R and S
-
Both Q and S
D
Correct answer
Explanation
Dark reaction occurs in stroma of chloroplast.
Statement Q is true, but statement S is false.
-
'Chlorophyll a'
-
'Chlorophyll b'
-
Carotenoids
-
Anthocyanins
C
Correct answer
Explanation
Carotenoids are very long-chain water-repelling pigments that are synthesized in the plastids of plant cells. These pigments primarily absorb the blue wavelengths, allowing the longer wavelengths to be scattered and producing the yellow colour.
-
photosynthesis
-
photoreceptors
-
photolysis
-
photons
C
Correct answer
Explanation
Photolysis is the light-driven decomposition of water into hydrogen and oxygen, occurring during photosynthesis' light-dependent reactions. Chlorophyll absorbs light energy to split water molecules, releasing electrons for the electron transport chain and oxygen as a byproduct.
-
first
-
second
-
third
-
all of these
-
stroma
-
thylakoids
-
leaves
-
none of the above
A
Correct answer
Explanation
The light-independent reactions, also known as the Calvin cycle, occur in the stroma of the chloroplast. The stroma is the fluid-filled space surrounding the thylakoids where CO2 fixation and sugar synthesis take place. Light-dependent reactions occur in the thylakoid membranes.
-
collenchyma
-
chlorenchyma
-
sclerenchyma
-
aerenchyma
-
gross primary production
-
net primary production
-
biomass
-
a pyramid of energy
A
Correct answer
Explanation
The total amount of energy that plants assimilate by photosynthesis is called gross primary production.
-
nitrogen cycle.
-
hydraulic cycle.
-
petrological cycle.
-
food chain cycle.
D
Correct answer
Explanation
During photosynthesis process, solar energy is being transferred through the food chain. It is being transformed from one chemical form to another. In this process, much of the food energy is lost as metabolic heat.
-
75 - 80%
-
25 - 30%
-
10 - 15%
-
1 - 2%
D
Correct answer
Explanation
Only about 1-2% of the water absorbed by plant roots is actually used in photosynthesis to produce carbohydrates. The remaining 98-99% is lost through transpiration. This water loss is necessary to create the transpiration pull that drives water and mineral absorption from soil, making it essential despite the inefficiency.