Why is not any one parameter good enough to demonstrate growth throughout the life of a flowering plant?

Which is the particular type of drug that is obtained from the plant whose one flowering branch is shown below?

Which one of the following statements regarding post-fertilization development in flowering plants is incorrect? (A) Ovary develops into fruit (B) Zygote develops into embryo (C) Central cell develops into endosperm (D) Ovules develop into embryo sac

Examine a few flowers of any cucurbit plant and try to identify the staminate and pistillate flowers. Do you know any other plant that bears unisexual flowers ?

In a beautiful valley, there was a village. When trains passed from the village, the whistle and the sound of train, mixed with the sound of waterfall, seemed to be very pleasant to everyone. Hence, children of that village used to play near the railway track. Once on a very light foggy day, a group of children found that a fish plate was missing from the track. As such, all the villagers were worried. Prashant, one of the children, suddenly put his ear to the line and tried to know whether a train is coming or not. He knew a train is coming. He asked his friends to inform the railway cabin crew and he himself put off his red shirt and started running towards the train, waving his red shirt. The driver and cabin man got the alert signal in time and thus a major accident was averted. Why did Prashant use his red shirt instead of any other coloured shirts ?