The various factors responsible for grain loss during storage are:
(i) Biotic factors: Insects, Rodents (mice), Birds, Fungi, Bacteria, Mites, ect.
(ii) Abiotic factors: Inappropriate temperature, moisture, moisture contents of seeds, dampness of storage godown ect.
The above factors cause loss in weight, degradation in quality, discolouration of produce ect.
Measures for safe storage of grains: 
(i) Drying: Grains to be stored ideally should contain below 9% water content/moisture. When grains are harvested, usually contain 15 to 35% moisture. These freshly harvested grains are dried under the sun and then in shade to reduce the moisture content. Commercially grains are dried by mechanical driers with hot air blowing process.
(ii) Maintenance of hygiene: Grains should be kept in godowns that
(a) are very clean and do not have garbage, refuse, webs etc.
(b) do not have cracks, holes in walls, floor and ceilings.
(c) have clean and fresh gunny bags or are well treated with fumigate or dried under sun.
(d) have earthen pots, if to be used for storage, well cleaned and properly exposed to sun before use.
(iii) Prophylactic treatment: Godowns, gunny bags to be used for storage must be properly treated with fungicides, insecticides and other required pesticides by dusting, spraying or fumigation. Insecticides and fungicides should be mixed with grains that .are to be used for seed sowing.
(iv) Use of improved structures: Structures such as Pusa Bin, Pusa Cubicle, Pusa Kothar and Pant Kuthla can be used for storage purpose.
(v) Treatment of the surface area of the store house should be done by spraying mixture of BHC WP (50%), Pyrethrum (2.5 EC) and Malathion (50 EC) for controlling pests.
(vi) Fumigation of the store houses by chemicals such as aluminium phosphide tablets should be done.

It is very necessary to replenish forests for the following reasons:
(i) Rainfall: Trees give out enormous amount of water during transpiration. This water vapour helps in the formation of rain clouds. If trees are destroyed and not replenished the rainfall in the area will reduce. This may lead to less number of trees to grow.
(ii) Soil erosion: If trees are cut at a large rate the soil becomes barren. The top soil which is rich in organic matter will be washed away by water or carried away by wind. Thus reduction in rainfall and soil erosion may lead to the formation of desert.
(iii) Carbon dioxide-oxygen balance: Forests have very large number of trees. They give out \({ O }_{ 2 }\) and take in \({ CO }_{ 2 }\) in day time by the process of photosynthesis. Thus they help in maintaining carbon dioxide-oxygen balance in the atmosphere.

The factors which are important for maintaining good health  and if not present will lead to diseases are:
(i) Availability of proper balance diet (food) in sufficient quantity and clean water.
(ii) Good environment or surroundings that includes physical environment, Public cleanliness is important.Stagnation of dirty water, presence of open drains, garbage, in the surrounding cause spread of diseases.
(iii) Good special environment is an important factor is maintaining good health.If people mistreat each other or some particular people, they are mentally ill, they cannot lead happy life.
(iv) Good economic condition or job is the major factor which causes disease.For example, to provide good and proper food, clean clothes and hygienic conditions, proper social relationship, good economic conditions are essential.

Time period. The time taken by an oscillating body to complete one oscillation is called its time period. It is denoted by T. Its SI unit is second (s).
Frequency. The number of oscillations or vibrations completed by an oscillating body in one second is called its frequency. It is denoted by v (Greek letter nu).
SI unit of frequency=per second (s^-1) = cycles per second (cps) = hertz (Hz).
Relation between time period and frequency:
Let T=time period of an oscillating body. Then number of oscillations completed in T second = 1
Number of oscillations completed in 1 second =\(\frac { 1 }{ T } \)
But number of oscillations completed in 1 second = frequency (v)
∴ \(v=\frac { 1 }{ T } \)
Hence frequency is equal to the reciprocal of time period.

Non-uniform motion .If an object covers unequal distances in equal intervals of time,it is said to be in non-uniform motion. Most of the motions seen in our daily life are non-uniform. For example,if we drop a ball  from the roof of a building we will note that the ball covers 4.9 m in the 1st second 14.7 m in the 2nd second 24.5 m in the 3rd second , and so on That is the ball covers increasingly larger distances in successive seconds as it falls down. Thus, the motion of a freely falling body is non-uniform
Other examples of non-uniform motion:
(i) A stone dropped from the top of a building
(ii) A ball thrown vertically upwards
(iii) The motion of a train as it leaves the station
(iv) The motion of a bus as it approaches a bus-stop
(v) The motion of a ball rolling down an inclined plane.

(i)Cathode rays travel in straight lines and thus cast shadows of objects placed in their path.
(ii)Cathode rays possess material particles because they can rotate a light paddle wheel placed in their path.
(iii)They are deflected towards positive plate thus showing that theses are negatively charged particles knowns as electrons
(iv)They ionise gas through which they pass
(v)They are deflected by magnetic fields.
(vi)The nature of cathode rays is independent of the material of cathode.Hence they are common constituents of all matter
(vii)They can penetrate through thin metallic sheet
(viii)They can produce X-rays
(ix)The mass of a cathode ray particle is very-very small as compared to the mass of the atom from which it is formed

Because of the high temperature inside sun or stars, particles of hydrogen gas or helium get ionised and plasma is created.The plasma helps the sun or stars to glow.

It is not correct to say that fluorescent tube contains plasma.In fact, fluorescent tube contains helium or some other rare gas.The particles of the gas gets ionised,i.e., charged in the presence of high voltage applied.These charged particles are called plasma which actually glow.

After rain, the air gets saturated with water vapour.This results in drop of evaporation of sweat from our body and hence the body stops losing excessive heat.This makes us uncomfortable.

Boiling point of a liquid increases with pressure.Because b. pt. is the temperature at which the pressure of the liquid becomes equal to the atmospheric pressure.Thus if the atmospheric pressure is increased, more heat will have to be given to make it equal to the existing pressure.Thus b. pt. increases with the pressure above the liquid.

The pressure exerted by a gas is the force exerted by gas particles per unit area on the walls of the container.It is expressed in pascal(Pa).1 atmosphere= \(1.01\times { 10 }^{ 5 }\) Pa.The pressure depends on the average kinetic energy of the colliding particles which depends on temperature of the gas.

Ice: It is rigid and has definite shape.It can be stored without a container.
Water: It is fluid and has no definite shape.It cannot be stored without a container.

Intermolecular force of attraction between particles of a matter makes it a solid, a liquid or a gas.High intermolecular force of attraction results in closely packed particles which makes a solid.Weaker intermolecular force of attraction means particles are less compactly packed which makes a liquid.Almost no intermolecular force of attraction allows the particles to move randomly giving a gas.

Characteristics of matter
(i) Particles of matter have space between them.Example: When a small amount of sugar is added to water, it mixes without increase in volume.
(ii) Particles of matter are moving.Example: When a crystal of copper sulphate is added to water, blue colour of copper sulphate diffuses throughout the whole volume of water.
(iii) Particles of matter attract each other.Example: If you put your figure across running water from a tap, it breaks but when finger is removed, the stream of water regains.
(a) Diffusion
(b) Non-rigidity of liquid water.

The specific function of cardiac muscle is to contract and relax rhythmically throughout life.