Write an experiment to observe the structure of all the parts of the flower. (Note: figure is compulsory) (Write Aim,Apparatus, observation and inference.)
Answers
Answer:
Aim: To study Pollen germination and growth of Pollen tube.
(2) Materials required: Flower, needles, Safranine stain, glycerine, coverslips, microscope.
(3) Procedure:
(1) Take out the pistil from a Portulaca flower.
(2) Stain the isolated pistil and mount in glycerine, Press gently, observe under dissecting
microscope.
(3) Take out carefully each germinated pollen and count.
(4) Mount a pollen in glycerine and observe under compound microscope.
(4) Observations:
(1) Observe many pollen grains germinating over stigma. The growth of the pollen tube is
stimulated by sugary substances secreted by the stigma.
(2) Pollen tube carrying with it tube nucleus and the generative nucleus.
(3) The generative nucleus divides forming two male gametes.
(4) Count the number of germinated pollen grains.
(5) Precautions:
(i) Mounting should be free from air bubbles.
(ii) Material should be moderately stained.
(iii) Use the clean s