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Question
The top part A of the flask-shaped reproductive organ X in the flower of a plant secrets a surgery substance into its lower part B which goes towards the bottom part C of the flask-shaped organ. When a tiny grain D coming from the top part E of another reproductive organ Y i the flower falls on part A, it grows a long tube F through the organ X i response to the sugary substance and reaches the bottom part C of flask-shaped organ to carry out fertilisation.
(a) Name parts (i) organ X, and (ii) organ Y, inside the flower?
(b) Name parts (i) A (ii) B, and (iii) C, of flask-shaped organ.
(c) Name (i) grain D, and (ii) part E of organ Y.
(d) Name the tube F.
(e) What is the phenomenon of growing a long tube in response to sugary substance in the process of fertilisation in a flower known as?
Solution
(a) (i) X is the carpel and (ii) Y is the stamen.
(b) (i) A is the stigma, (ii) B is the style and (iii) C is the ovary of the flask-shaped organ.
(c) (i) D is the pollen and (ii) E is the anther.
(d) F is the pollen tube.
(e) The phenomenon of growing a long tube in response to a sugary substance in the process of fertilisation in a flower is known as chemotropism.
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