Chapattis made from wheat only swell up but bread becomes spongy, soft and easy to digest. Why is it so?

Radiation of intensity 0.5 xx 10^-4 W//m^2 falls on the emitter in a photoelectric set-up. The emitter (cathode) is made up of potassium and has an area of 5 cm^2 . Let us assume that the electrons from only the surface are knocked off by the radiation. According to the wave theory,what will be the time required to notice some deflection in the microammeter connected in the circuit? (Given the metallic radius of potassium atom is 230 pm and work function of potassium is 2.3 eV.)

Bring ‘active dry yeast’ from the market. Mix a spoonful of yeast, two poonfuls sugar with «sufficient quantity of lukewarm water in a bottle. Fix a colourless, transparent balloon on the mouth of that bottle. Find out how to use the solution prepared in the above experiment, to make bread. Follow the recipe and make the bread. Find out and note down the reasons why the dough rises and makes the bread spongy.

The countries which do not have oil reservoirs in their land import oil from other countries. But sometimes during transporting oil through sea routes, accidental oil spilling occurs. This oil spilled in the ocean may prove fatal and toxic to aquatic animals. Therefore, removel of this spilled oil is essential for protection of aquatic life. For removing this oil layer, certain microbes like Pseudomonas spp. and Alcanivarax borkumensis are used. These microbes have the ability to destroy the pyridines and other toxic chemicals. The hydrocarbonoclastic bacteria (HCB) are able to decompose the hydrocarbons and bring about the reaction carbon with oxygen resulting in formation of C O 2 and water. Like oil spills cause damage to aquatic life. plastic forms the major part of the garbage on land. Plastics are difficult to degrade as they are made up of PET. By research, various species like Vibrio and Idenoella sakaiensis which can degrade PET have been identified. There are certain species of microbes which can decompose rubber from garbage. Based on the given paragraph answer the following question.Why should there be a ban on plastic bags ?