$3$Student to attempt either option-(A) or (B) : (A) (a) Distinguish between the two cells enclosed in a mature male gametophyte of an angiosperm. (b) Study the diagram given below showing the modes of pollination. Answer the questions that follow. 2025_CBSE_Biology_Set_Region1_Subset_Set1_Q32__b_p11_68

2025_CBSE_Biology_Set_Region1_Subset_Set1_Q32__b_p11_68

(i)The given diagram shows three methods of pollen transfer in plants. Examine them carefully and write the technical terms used for pollen transfer methods '1', '2' and '3'.(ii)How do the following plants achieve pollination successfully ?

(a) Water lily (b) Vallisneria

(iii)Write advantages of pollen transfer in method '3'.

OR

(B) Given below is the diagram of human ovum surrounded by a few sperms. Observe the diagram and answer the questions that follows :(i)Compare the fate of sperms 'P', 'Q' and 'R' shown in the diagram.(ii)Write the role of Zona pellucida in this process.(iii)Analyse the changes occurring in the ovum after the entry of sperm.(iv)How acrosome and middle piece of a human sperm are able to play an important role in human fertilization ?

Biology · Sexual Reproduction in Flowering Plants