IGNOU BBYCT-135 December 2025 Previous Year Question Paper

Q1.(a) State whether the following statements are 'True' or 'False' : 4x1=4

(i) Seeds of castor are exalbuminous.

(ii) Endosperm absorb nutrients from surrounding cells with the help of integuments.

(ii) Stomata in the epidermis help in gas exchange.

(iv) Pollination brought by bat is called chiropterophily.

(b) Fill in the blanks : 4x1=4

(6) Mature seed containing persistent endosperm are called as -

(ii) The process of embryo development from an unfertilized egg is called as Gii) Finger like wall projections in synergids are known as_ the

(iv) Ray cell contains duct.

(c) Match the items given under Column 'A' with those given under Column 'B': 4xi=2 Column 'A' Column 'B'

(A) Cork cell @) Dicot plant

(B) Cystolith

(ii) Root hair

(C) Trichoblast Gii) Calcium carbonate crystal

(D) Crescent shaped

(iv) Non-living guard cell and impermeable to gases and water

Q2.Differentiate between any two of the following : 2x5=10

(6) Bulliform cells and Silica cells

(ii) Meristematic tissues and Permanent tissues

(ii) Tenuinucellate and Crassinucellate

Q3.(a) Describe the root apex organisation with the help of histogen theory. 5

(b) Explain briefly the main features of unusual secondary growth in roots.

Q4.Define the term ‘guard cells’. How do guard cells control stomatal pore opening and closing ? Discuss with the help of an appropriate diagram.

Q5.(a) Give the general account of adaptations in xerophytes. 5

(b) Define polyembryony. Discuss its potential applications.

Q6.(a) Discuss the functions of suspensor with examples. 5

(b) Discuss the development of monosporic embryo sac with examples.

Q7.(a) What are pneumatophores ? Discuss their functions. 5

(b) Define apomixis. Write a detailed account of various types of apomixis.

Q8.Write short notes on any four of the following : 4x2i = 10

(i) Sclereids

(ii) Heartwood

(iii) Pollen sterility

(iv) Composite endosperm

(v) Velamen 4x1=4 2x5=10 4x25=10 (४) aera