Page 50 - Biology - XII
P. 50

VIVA VOCE


           Q1.  How many parts does meiosis cell division include?
          Ans.  Two

           Q2.  Mention the last (5th) substage of prophase I.
          Ans.  Diakinesis
           Q3.  How can one identify metaphase I?
          Ans.  It has only one set of chromosomes at equator.

           Q4.  How many daughter nuclei are present at the end of telophase II?
          Ans.  Four
           Q5.  What will be the chromosome number of gametes of a diploid individual?
          Ans.  Haploid

           Q6.  The chromosomes in Leptotene stage of meiosis is ___________ .
          Ans.  slender and thin

           Q7.  Mention the type of microsporogenesis in monocotyledons.
          Ans.  Successive types

           Q8.  Why is the meiosis division I also known as heterotypic division?
          Ans.  Hetero means diff erent. This is because the chromosome number of the daughter cells is diff erent
                 from the parent cell, i.e. it is reduced or halved.

           Q9.  What is meiosis?
          Ans.  Meiosis is a type of cell division that takes place in gonads of animals and in ovary and anther
                 of  plants.
          Q10.  Why do you tease the material? OR What is teasing?
          Ans.  Teasing is to separate or free the material from its covering or other binding (connective) tissues.

          Q11.  Can you see all the stages in a slide?
          Ans.  No, it is not easy to fi nd or locate all the stages in a single slide.

          Q12.  How can you identify cells/stages of meiosis II?
          Ans.  Any stage with two sets of identical pattern of arrangement of chromosomes confi rms meiosis II
                 stage (except telophase II where four cells are seen).
          Q13.  What is the chromosome number of the daughter cells produced by meiosis cell division?
          Ans.  Half the number of parent cells (n)

          Q14.  Why did you use onion buds?
          Ans.  The buds develop into fl ower. The fl ower has male and female parts. The anther is to be used for
                 study, hence it was used.
          Q15.  Why do you tap the material? OR Why do you press the material hard?
          Ans.  This is done because the material has cluster of cells. The tapping or pressing them scatters them or
                 spreads them uniformly. It forms a squash.
          Q16.  How can you identify a metaphase I stage?
          Ans.  The chromosomes are arranged on the equator of a single cell.




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