Nitcotiana tabacum, a Short-Day Plant, when exposed to more than critical period of light fails to flower.Explain.

For short day plants, the critical period is.......

The plant require light duration more than critical day length is called as______

Both a short day plant and a long day plant can flower simultaneously in a given place.' Explain.

Some varieties of wheat are known as spring wheat while others are called winter wheat Former variety is sown, and planted in spring and It is harvested by the end of the same season. However, winter varieties, if planted in spring, fail to flower or produce mature grains within aspan of a flowering season. Explain, why? Mineral nutrition.

State whether the following statements are true or false : ( If a statement is false , correct it and rewrite it.) : When red light falls on the eyes ,the cells responding to red light get excited more than those responding to other colours and we get sensation of red colour.

Short plants growing under the thick canopy of a rainforest receive filtered light but still perform photosynthesis. Explain.

Question based on paragraph While playing in a garden, Rahul noticed some ornamental plants. When he observed them carefully, he found some Powdery spots on the posterior surface of leaflets of plant. He was curious to observe the flowers or fruits of these plants, but he could not find any of these. Give two more examples of plants belonging to same division.

When a surface is irradiated with light of wavelength 4950 overset(@)(A) ,a photocurrent appears which vanishes if a retarding potential greater than 0.6 V is applied across the phototube.When different source of light is used,it is found that the critical retarding potential is changed to 1.1 V.Find the work function of the emitting surface and the wavelength of the second source

Long day plants can be made to flower even under short day conditions if treated with.........

The threshold wavelength of tungsten is 2.76 xx 10^-5 cm : Explain why no photoelectrons are emitted when the wavelength is more than 2.76 xx 10^5 cm .