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The correct OPTION is (b) False

To explain I would say: The C4 pathway uses 5 ATP and 2 NADPH MOLECULES as its energy SOURCE. This is higher than the energy requirement in Calvin CYCLE but C4 can be effective under HOT and less water content.

The correct answer is (a) True

The EXPLANATION is: Carotenoids function as secondary light absorbers during PHOTOSYNTHESIS and DRAW excess AWAY from excited CHLOROPHYLL molecules (to prevent the formation of singlet oxygen) to dissipate it as heat.

Correct option is (b) C4H4O5

Explanation: The oxaloacetic ACID is formed when PHOSPHOENOLPYRUVATE reacts with CO2. This is the FIRST product of the pathway which is a four carbon COMPOUND.

Correct option is (d) Common ice PLANT

For EXPLANATION I would say: Common ice plant is an facultative CAM plant. It usually does not undergo CAM photosynthesis but it undergoes CAM photosynthesis when it is under stress condition, like shortage of water, CO2, ETC.

Correct answer is (d) 6

Best explanation: The Calvin cycle needs to be repeated six times to PRODUCE one glucose molecules. Glucose being a six CARBON ATOMS GETS its carbon atoms from G3P complex. The FIRST five G3P molecules are regenerated and only the sixth G3P molecule completes the glucose.

The correct CHOICE is (b) Malate

Easiest explanation: Malate is formed as a final PRODUCT of the C4 PATHWAY. Malate in the final step REGENERATES the pyruvate and FIXES CO2.

The correct choice is (c) CAROTENOIDS

To EXPLAIN: Carotenoids are coloured pigments found in plants and some other PROKARYOTIC algal cells. Carotenoids do not directly CONTRIBUTE to the photosynthesis, but they protect the plants from UV RADIATION.

Correct ANSWER is (c) Cytochrome b6f complex

The best explanation: Plastoquinol – plastocyanin REDUCTASE is also known as the Cytochrome b6f complex. It is an enzyme that HELPS to transfer electrons from Photosystem II to Photosystem I.

Correct choice is (c) 2500

The explanation: Scientists Emerson and ARNOLD found that in a photosynthetic REACTION 2500 molecules of chloroplast is required to PRODUCE one molecule of OXYGEN. They also REQUIRE eight photons in the process of producing one molecule of oxygen.

The correct OPTION is (b) False

Easiest explanation: Calvin cycle takes place in the STROMA of the chloroplast of the cell. The stroma contains the necessary energy COMPOUNDS for the PREPARATION of carbohydrate.

The correct OPTION is (B) ACTION spectrum

The best I can explain: Action spectrum is a plot of relative rate of photosynthesis induced by lights of different wavelengths. The spectrum IDENTIFIES wavelengths that are EFFECTIVE in inducing a physiological response.

Correct answer is (c) 4 – 6 MICROMETER

For explanation I would say: Chloroplasts are generally 4 – 6 micrometer in DIAMETER and 2 – 4 micrometer in thickness. These chloroplasts are ROUND, oval and DISC shaped organelles.

The correct CHOICE is (b) ATP, NADPH

Explanation: Energy from sunlight is absorbed and saved in the form of chemical energy in two types of biomolecules in plants NAMELY ATP and NADPH. ATP is the cell’s PRIMARY source of energy and NADPH is the cell’s primary source of REDUCING POWER.

The correct option is (c) Carbonic anhydrase

Best explanation: Carbonic anhydrase is an enzyme, which plays the role of catalyst in the FIRST CO2 fixation STEP of C4 pathway. It helps the CO2 molecule to bind to the ACTIVE site of RuBisCO.

Correct OPTION is (b) D1

Explanation: The DISORDER in photophosphorylation due to high INTENSITY light causes an accumulation of reactive OXYGEN species. This causes them to bind with D1 protein and INACTIVATES them.

Correct ANSWER is (a) 100

Easy explanation: ARABIDOPSIS thaliana commonly known as mouse-ear cress has AROUND 100 chloroplasts in each cell. The number of chloroplasts in each ORGANISM differ from SPECIES to species depending on the need of energy from photosynthesis.

The correct answer is (b) False

To explain: C4 PLANTS suppress photorespiration and thus REQUIRE high light, high TEMPERATURE and low carbon-dioxide conditions. Thus only a handful of C4 plants are found in cold climates. Most of them are found in temperate REGIONS.

The correct choice is (a) Sugarcane

Best explanation: The plants that PRODUCE four carbon SUGAR molecules by taking atmospheric CO2 is known as C4 plants. These plants UNDERGO Hatch – SLACK PATHWAY.

Right answer is (c) Leaf variegation

Explanation: Leaf variegation is caused by the deficiency of chloroplast DUE to mutation. BLIGHT SPOT, Leaf spot and Powdery MILDEW are caused by FUNGI.

Correct option is (c) Spirulina

To elaborate: The spirulina, which belongs to the community of cyanobacteria, commonly known as blue GREEN ALGAE, has photosynthetic pigments in it. They predominantly CONTAIN CHLOROPHYLL a.

The CORRECT option is (a) β-carotene

Easy EXPLANATION: β-carotene is a carotenoid, a PIGMENT that ACTS as accessory light absorber during photosynthetic reaction. It has a linear system of conjugated double bonds.

Correct choice is (c) Mesophylls

The best I can EXPLAIN: The C4 pathway takes place in the mesophyll cells of the plant system. They are DARK reaction and does not REQUIRE light to take place. The Calvin CYCLE on the other hand takes place on the bundle sheath.

The correct choice is (b) ATP synthase

Easy EXPLANATION: ATP synthase helps in the flow of protons from THYLAKOIDS to the STROMA. It also helps in the PRODUCTION of ATP. It yields 1 molecule of ATP for every 2 PHOTONS.

The correct ANSWER is (a) True

Best explanation: PHOTOSYSTEM II happens before photosystem I but the name I and II DENOTES the ORDER of their discovery. The electrons usually flow from photosystem II to photosystem I.

The correct answer is (b) lower

Explanation: ENERGY of photons are INVERSELY PROPORTIONAL to the wavelength given by the formula E=hv. So the light having lower wavelength will have higher energy and vice VERSE.

Right choice is (c) CARBOHYDRATES

Easy EXPLANATION: The second stage of events involved in PHOTOSYNTHESIS is REFERRED to as light-independent (dark) reactions. In these carbohydrates are synthesized from carbon DIOXIDE using energy stored in ATP and NADPH.

The correct CHOICE is (b) False

To elaborate: The CAM pathway STARTS at NIGHT when there is lower TEMPERATURE. This is due to the mechanism that reduces water loss by evatranspiration.

Right option is (a) 18

To explain I would say: Calvin cycle uses 18 molecules of ATP and 12 molecules of NADPH to SYNTHESIZE one molecule of glucose. These ATP and NADPH are produced from the light REACTIONS of PHOTOSYNTHESIS.

The correct choice is (a) Melvin Calvin

Explanation: Melvin Calvin discovered the C3 cycle, otherwise known as Calvin cycle in PHOTOSYNTHESIS pathway of Chlorella. He used RADIOISOTOPE CARBON – 14 to mark the PATH of the metabolism in the C3 plants.

The correct answer is (a) GREEN SULPHUR bacteria

The best explanation: Chlorosomes are antenna COMPLEXES(protein complexes used to harvest light energy) that are FOUND in Green Sulphur bacteria. These complexes are different from other antenna complexes by their protein composition and size allowing the bacteria to harvest light energy in extreme conditions.

The correct CHOICE is (a) Chloroplast

Easy explanation: The photophosphorylation OCCURS in the thylakoids of chloroplast. Because photophosphorylation requires sunlight to OCCUR and chloroplast is the site for absorption of light.

Right option is (d) Vitamin K

Best explanation: Vitamin K also KNOWN as phylloquinone acts as an ELECTRON acceptor during photosynthesis. It DONATES a hydrogen molecule and helps in the electron TRANSPORT CHAIN.

The correct choice is (a) Cactus

For explanation: CAM is KNOWN as crassulacean ACID metabolism. These CAM plants fix CO2 in the arid and HOT CLIMATE regions.

Right option is (c) Glucose

To elaborate: The Calvin cycle PRODUCES THREE carbon sugar MOLECULES by taking 3 molecules of CO2 from the atmosphere. These three carbon sugars are LATER converted to six-carbon sugar called glucose.

Correct OPTION is (d) Yeast

Explanation: Yeast is a heterotroph which cannot synthesize its own FOOD by the use of SUNLIGHT. It is devoid of the photosynthetic pigments and PHOTOPHOSPHORYLATION requires these pigments.

The correct answer is (B) Chlorophyll b

Explanation: Chlorophyll b is a PIGMENT, which is yellow in colour. This pigment is responsible for the vast ABSORPTION of SUNLIGHT. It is present in the light absorbing ANTENNA of the plants.

The correct choice is (a) True

The EXPLANATION is: The MEMBRANE of THYLAKOIDS is responsible for photosynthesis.They entrap the solar ENERGY and provide it for the photosynthesis.

The correct option is (a) True

The EXPLANATION is: Pigments are compounds that appear visibly COLORED because they only absorb light of particular WAVELENGTHS. Chlorophyll is a green colored PIGMENT FOUND in chloroplasts of plants.

The correct ANSWER is (c) PHOSPHOENOLPYRUVATE carboxylase

For EXPLANATION: The phosphoenolpyruvate carboxylase enzyme is used to catalyze bicarbonate to oxaloacetate and phosphate. This is one of the important mechanism in the carbon FIXATION in CAM plants.

Right CHOICE is (c) Kranz anatomy

Explanation: Kranz has the meaning “WREATH” in German anatomy. There are two rings SURROUNDING the vascular BUNDLE. The inner ring is made of bundle sheath while the outer ring is made up of mesophyll cells.

Correct ANSWER is (a) 4

To explain: The AQUATIC plants can also UNDERGO CAM photosynthesis. There are about 4 genera of plants. They also follow the same pathway as the TERRESTRIAL CAM plants.

The correct CHOICE is (a) True

The explanation is: CHLOROPLASTS cannot be SYNTHESIZED by the cell itself. They have their own DNA and it divides by binary fission PROCESS like PROKARYOTES.

The CORRECT choice is (a) True

The BEST I can explain: The C3 plants are most commonly found in TEMPERATE and COLD regions. They can do photosynthesis efficiently in cold climates, where there is LESS loss of water.