IGNOU BBYCT-137 June 2023 Previous Year Question Paper

Q1.(a) State whether the following statements are true or false : 4×1=4

(i) The water potential is less negative in the xylem than in the soil water.

(ii) Both cyclic and non -cyclic electron transport operate in photosynthetic bacteria.

(iii) In Cyanobacteria, Nitrate reductase is located in the photosynthetic membranes.

(iv) The sources and sinks for solute transport are always fixed.

(b) Fill in the blanks : 4×1=4

(i) The source of O 2 liberated in photosynthesis is .

(ii) The upward movement of water is

(iii) In the rainy season, the wood of doors gets swelled up due to .

(iv) and ions are required for chlorophyll synthesis.

(c) Match the items given under Column ‘A’ with those given under Column ‘B’ : 4× 2=2 Column ‘A’ Column ‘B’

(a) Molecular Oxygen

(i) Ketoglutarate

(b) Electron Acceptor

(ii) Acetyl CoA

(c) Pyruvate dehydrogenase

(iii) Cytochrome C

(d) Decarboxylase

(iv) Hydrogen Acceptor [ 3 ]

Q2.Differentiate between the following pairs of terms : 4×2 2=10

(i) Photophosphorylation and Oxidative phosphorylation

(ii) Competitive and Non-competitive inhibition

(iii) Diffusion and Osmosis

(iv) C3 and C4 plants

Q3.Explain Krebs cycle . Highlight the metabolic intermediates and sites for NADH, FADH 2 and ATP production.

Q4.(a) Define the term ‘Vernalization’. What role does it play in agriculture ? 5

(b) Explain active transport of metabolites through ionic pumps.

Q5.(a) Explain the mechanism of allosteric enzyme regulation. 5

(b) Discuss the mechanism of opening and closing of stomata. 5 [ 4 ]

Q6.(a) Discuss the functions of essential elements.

(b) What is stress ? Discuss temperature induced stress.

Q7.Write short notes on any two of the following : 5×2=10

(i) Protoosmotic model for phloem transport

(ii) Photorespiration

(iii) Bioassays for auxins

(iv) Phytochrome-mediated responses 2023 -137 4×1=4 4×1=4 2=2 CoA 4×2 2=10

(iv) C3 NADH, FADH2 ATP BBYCT–137 5,9

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