The top part A of the flask-shaped reproductive organ X in the flower of a plant secretes 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 in the flower falls on part A, it grows a long tube F through the organ X in response to the sugary substance and reaches the bottom part C of flask � shaped organ to carry out fertilisation.
(a) What is (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 a sugary substance in the process of fertilization in a flower known as?
(a) (i) Inside the flower, the organ X is carpel (a female reproductive organ).
(ii) Inside the flower, the organ Y is stamen (a male reproductive organ).
(b) (i) Part A of flask shaped organ is stigma.
(ii) Part B of flask shaped organ is style.
(iii) Part C of flask shaped organ is ovary.
(c) (i) Grain D of organ Y (stamen) is pollen grain.
(ii) Part E of organ Y (stamen) is anther.
(d) Tube F is the pollen tube.
(e) Due to chemical stimulus, the growth of a plant part is known as chemotropism. For example, a sugary substance can induce to the growth of pollen tube towards the ovule. Here, sugary substance works as a stimulus and this process represents the positive chemotropism.