Ans: (a)-crop.
(b)-preparation.
(c)-float.
(d)-water,nutrients.

Ans;-(i)-(e),(ii)-(d),(iii)-(b),(iv)-(c)

Ans:- (a)Paddy, maize,
(b)Wheat, gram,

Ans:-(a) Preparation Of Soil
The preparation of soil is the first step before growing a crop. One of the most important tasks in agriculture is to turn the soil and loosen it. This allows the roots to penetrate deep into the soil. The loose soil allows the roots to breathe easily even when they go deep into the soil. The loosened soil helps in the growth of earthworms and microbes present in the soil. These organisms are friends of the farmer since they further turn and loosen the soil and add humus to it.
(b) Sowing
Sowing is the most important part of crop production. Before sowing, good quality seeds are selected. Good quality seeds are clean and healthy seeds of a good variety. Farmers prefer to use seeds which give a high yield. Due to which selection of seed required. This selection is a good method for separating good, healthy seeds from the damaged ones. Before sowing, one of the important tasks is to know about the tools used
for sowing seeds.
(c) Weeding
The removal of weeds is called weeding. Weeding is necessary since weeds compete with the crop plants for water, nutrients, space and light. Thus, they affect the growth of the crop. Some weeds interfere even in harvesting and may be poisonous for animals and human beings. Farmers adopt many ways to remove
weeds and control their growth. Tilling before sowing of crops helps in uprooting and killing of weeds, which
may then dry up and get mixed with the soil. The best time for the removal of weeds is before they produce flowers and seeds.
(d) Threshing
In the harvested crop, the grain seeds need to be separated from the chaff. This process is called threshing. This is carried out with the help of a machine called ‘combine’ which is in fact a combined harvester and thresher .Farmers with small holdings of land do the separation of grain and chaff by winnowing.

Ans:- 1. Fertiliser is an inorganic salt, manure is a natural substance obtained by the decomposition of cattle dung, human waste and plant residues.
2. Fertiliser is prepared in factories., Manure can be prepared in the fields.
3. Fertiliser does not provide any humus to the soil, Manure provides a lot of humus to the soil.
4. Fertilizers are very rich in plant nutrients like nitrogen, nutrients, phosphorus and potassium. Manure is relatively less rich in plant nutrients.

Ans:- The supply of water to crops at different intervals is called irrigation. The main methods used for irrigation which conserve water is as follows:-
(a) Sprinkler System
This system is more useful on the uneven land where sufficient water is not available. The perpendicular pipes, having rotating nozzles on top, are joined to the main pipeline at regular intervals. When water is allowed to flow through the main pipe under pressure with the help of a pump, it escapes from the rotating nozzles. It gets sprinkled on the crop as if it is raining. Sprinkler is very useful for sandy soil.
(b) Drip system
In this system, the water falls drop by drop just at the position of the roots. So it is called drip system. It is the best technique for watering fruit plants, gardens and trees. The system provides water to plants drop by drop Water is not wasted at all. It is a boon in regions where availability of water is poor.

Ans:- Wheat is an example of Rabi Crop and the crops grown in the winter season. Wheat does not requires a lot of water. Therefore, it is grown only in the winter season. Suppose wheat sown in the Kharif season then it will destroy due to heavy water in rainy season, so that farmers will not get better yield of wheat.

Ans:- Soil supplies mineral nutrients to the crop. These nutrients are essential for the growth of plants. In certain areas, farmers grow crop after crop in the same field. The field is never left uncultivated or fallow. Continuous growing of crops makes the soil poorer in certain nutrients.

Ans:- In a field many other undesirable plants may grow naturally along with the crop. These undesirable plants are called weeds. There are many ways to remove weeds and control their growth. Tilling before sowing of crops helps in uprooting and killing of weeds, which may then dry up and get mixed with the soil. The best time for the removal of weeds is before they produce flowers and seeds. The manual removal includes physical removal of weeds by uprooting or cutting them close to the ground, from time to time. This is done with the help of a khurpi. Weeds are also controlled by using certain chemicals, called weedicides, like 2,4-D. These are sprayed in the fields to kill the weeds. They do not damage the crops. The weedicides are diluted with water to the extent required and sprayed in the fields with a sprayer.

Ans:- 1. Ploughing the field
2. Preparation of soil
3.Sowing
4.Manuring
5.Irrigation
6.Harvesting
7. Sending crop to sugar factory

Ans;-(a) magnifying glass.
(b) nitrogen
(c) microorganism.
(d) bacteria

Ans:-a - (ii)
b - (ii)
c - (i)
d - (ii)
e - (iii)
f - (iii)

Ans:-(i)-(e),(ii)-(a),(iii)-(b),(iv)-(c),(v)-(d),(vi)-(f)

Ans:- Microorganisms or microbes are so small in size that they cannot be seen with the unaided eye. It can be seen with a magnifying glass or with the help of microscope.

Ans:- Microorganisms are classified into four major groups. These groups are bacteria, fungi, protozoa and some algae.

Ans:- Rhizobium

Ans:- Microorganisms are useful for commercial production of medicines and alcohol. Some microorganisms decompose the organic waste and dead plants and animals into simple substances and clean up the environment. Some microorganisms reside in the root nodules of leguminous plants. They can fix nitrogen from air into soil and increase the soil fertility. Some bacteria and blue green algae present in the soil fix nitrogen from the atmosphere and convert into nitrogenous compounds. Certain bacteria convert compounds of nitrogen present in the soil into nitrogen gas which is released to the atmosphere. Microorganisms are used for various purposes. They are used in the preparation of curd, bread and cake.
Microorganisms have been used for the production of alcohol Microorganisms are used for the large scale production of wine and acetic acid (vinegar). Microorganisms decompose dead organic waste of plants and animals converting them into simple substances.

Ans:- Microorganisms are harmful in many ways. Some of the microorganisms cause diseases in human beings, plants and animals. Such disease-causing microorganisms are called pathogens. Some microorganisms spoil food, clothing and leather. Pathogens enter our body through the air we breathe, the water we drink or the food we eat. They can also get transmitted by direct contact with an infected person or carried through an animal. Microbial diseases that can spread from an infected person to a healthy person through air, water, food or physical contact are called communicable diseases. Examples of such diseases include cholera, common cold, chicken pox and tuberculosis. There are some insects and animals which act as carriers of disease causing microbes. Housefly is one such carrier. The flies sit on the garbage and animal excreta. Pathogens stick to their bodies. When these flies sit on uncovered food they may transfer the pathogens. Whoever eats the contaminated food is likely to get sick. So, it is advisable to always keep food covered. Avoid consuming uncovered items of food. Another example of a carrier is the female Anopheles mosquito which carries the parasite of Maleria.

Ans:- Streptomycin, tetracycline and erythromycin are some of the commonly known antibiotics which are made from fungi and bacteria. When we are taking antibiotics, then It is important to remember that antibiotics should be taken only on the advice of a qualified doctor. Also we must finish the course prescribed by the doctor. If we take antibiotics when not needed or in wrong doses, it may make the drug less effective when we might need it in future. Also antibiotics taken unnecessarily may kill the beneficial bacteria in the body.

Ans:- The natural fibres like cotton, wool, silk, etc., are obtained from plants or animals. The synthetic fibres, in the other hand, are made by human beings. That is why some fibres are called synthetic

Ans:-(b)

Ans:- a - Artificial, Man-Made
b - Petrochemical
c - polymer

Ans:-Nylon fibres are very strong it can be proved by this examples, Nylon is used for making parachutes and ropes for rock climbing . A nylon thread is actually stronger than a steel wire.

Ans:- If we think of storing a food item, water, milk, pickles, dry food, etc., plastic containers seem most convenient. This is because of their light weight, lower price, good strength and easy handling. Being lighter as compared to metals, plastics are used in cars, aircrafts and spacecrafts, too.

Ans:- Such plastic which gets deformed easily on heating and can be bent easily are known as thermoplastics. Polythene and PVC are some of the examples of thermoplastics. These are used for manufacturing toys, combs and various types of containers. While there are some plastics which when moulded once can not be softened by heating. These are called thermosetting plastics. Two examples are bakelite and melamine.

Ans:-As we know that thermosetting plastics are such a plastic which when moulded once, cannot be softened by heating. Thermosetting plastics are poor conductors of heat and electricity. That is why Saucepan ,electric plugs, Switches, plug bord have plastic covering, and handles of screw drivers are made of thermosetting plastic.

Ans:-Plastic toys, Carry bags, Ball point pen, Plastic chairs ,plastic bowl are can be recycled while plastic covering on electrical wires and electrical switches cannot be recycled.

Ans:-As I think for summer season Rana must have to buy cotton shirt as cotton is a natural fiber, so it is less expensive also it dry up quickly, durable, readily available in the market.

Ans:- The waste created by plastics is not environment friendly. On burning plastics release poisonous gases. On dumping in the ground they may take years to degenerate. This is because of their non-biodegradable nature, for example; metals like iron get rusted when left exposed to moisture
and air. But plastics do not react with water and air. They are not corroded easily.

Ans:-Yes handle and bristles of a tooth brush must be made up of nylon. Beause nylon fibre is strong, elastic and light. It is lustrous and easy to wash. So, it became very popular for making.

Ans:- There are many things wrapped in plastic or packed in polythene bags. But plastic waste keeps getting accumulated in our homes. Ultimately, plastic finds its way in the garbage. Disposal of plastic
is a major problem. A material which is not easily decomposed by natural processes is termed as non-biodegradable. Since plastic takes several years to decompose, it is not environment friendly. It causes environmental pollution. Besides, the burning process in the synthetic material is quite slow and it does not get completely burnt easily. In the process it releases lots of poisonous fumes into the atmosphere
causing air pollution. Avoid the use of plastics as far as possible. Make use of bags made of cotton or jute when we go for shopping. The biodegradable and non-biodegradable wastes should becollected separately and disposed off separately.

Ans(i)-(d),(ii)-(c),(iii)-(a),(iv)-(b)

Ans:- Manufacturing synthetic fibres, they are named as Rayon, Nylon, Polyester and Acrylic. The different types of fibres differ from one another in their strength, water absorbing capacity, nature of burning, cost, durability, etc. Rayon is obtained from wood pulp, yet it is a man-made fibre. Nylon is another man-made fibre. In 1931, it was made without using any natural raw material (from plant animal). It was prepared from coal, water and air. Therefore by giving these example we can say that synthetic fibres are useful for conservation of forest.

Ans:-As we know that plastics are poor conductors of heat and electricity. That is why electrical wires have plastic covering, and handles of screw drivers are made of plastic. Also handles of frying pans are also made of plastic .It can be understand by this activity plastic cookware is used in microwave ovens for cooking food. In microwave ovens, the heat cooks the food but does not affect the plastic vessel.

Ans:-(a)

Ans:-(C)

Ans:-a - Reacive.
b - Good,Electricity.
c - Less.
d - Hydrogen gas.

Ans: a-(F)
b -(T)
c -(F)
d -(F)

Ans:- 1. Appearance- Metals are bright . Non metals.are dull
2. Hardness- Materials are ha metal materials are soft in case of Non metals.
3. Malleability-Metal shows this property.NOn metal does not show this property.
4. Ductility- Metal shows this property.NOn metal does not show this property.
5. Heat Conduction-Metals are good conductor of heat, NOnmetals are bad conductor of heat.
6. Conduction of Electricity- Metals are good conductor of Electricity , NOn metals are bad conductor of Electricity

(a) Aluminium foils are used to wrap food items.
Ans:- The property of metals by which they are good conductor of heat and electricity. Here aluminium foil is a good conductor of heat .Therefore, Aluminium foils are used to wrap food items. Due to which food items can be hot and can be eat after 3-4 hours.

(b) Immersion rods for heating liquids are made up of metallic substances.
Ans:- Immersion rods are good conductor of heat it absorbs heat and it is used for heating liquid .

(c) Copper cannot displace zinc from its salt solution.
Ans:- zinc is more reactive than copper .Due to which copper cannot displace zinc.

(d) Sodium and potassium are stored in kerosene.
Ans:- Sodium and potassium metal is very reactive. It reacts vigorously with oxygen and water. A lot of heat is generated in the reaction. It is, therefore, stored in kerosene.

Ans:-Suppose if we store lemon pickle in an aluminium utensil then lemon pickle reacts with aluminium utensil and produces hydrogen gas that burns with a ‘pop’ sound.

Ans:-(i)-(d),(ii)-(d),(iii)-(c),(iv)-(f),(v)-(b),(vi)-(a)

(a) Dilute sulphuric acid is poured on a copper plate?
Ans:-when a dilute sulphuric acid is poured on a copper plate then it produces hydrogen gas with ‘pop sound’.
(b) Iron nails are placed in copper sulphate solution?
Ans:-When Iron nails are placed in copper sulphate solution ,as we know that iron is -
Write word equations of the reactions involved.

(a) How will she find the nature of the gas ?
Ans:-A burning charcoal consist carbon and oxygen .But after specific reaction the gas which evolved through test tube is carbon dioxide gas. Nature of this gas is find out by the sound through which it can be identify.
(b) Write down word equations of all the reactions taking place in this process.
Ans:-The reaction taking place in this case is represented as - C+O2 -> Co2

Ans:- When we do police on any metal that time some mixed metal like Zinc, copper…….they looses their property due to which there is loss in its weight.

Ans:-The advantages of using CNG and LPG as fuel are given below
1. It is used for Power Generaion.
2. It is easy to transport through pipe.
3. It is used as a fuel for transport vehicles.
4. It is less polluting
5. it can be used directly for burning in home and factory.

Ans:-Bitumen a petroleum product used for surfacing of roads.

Ans:- About 300 million years ago the earth had dense forests in low lying wetland areas. Due to natural processes, like flooding, these forests got buried under the soil. As more soil deposited over them, they were compressed. The temperature also rose as they sank
deeper and deeper. Under high pressure and high temperature, dead plants got slowly converted to coal. As coal contains mainly carbon.And the slow process of conversion of dead vegetation in to coal is called carbonisation.

(a) Fossil fuels are , and
Ans;- Coal ,Petroleum and Natural Gas.
(b) Process of separation of different constituents from petroleum is called .
Ans:-Refining.
(c) Least polluting fuel for vehicle is .
Ans;-CNG.

(a) Fossil fuels can be made in the laboratory. (T/F)
Ans:-F
(b) CNG is more polluting fuel than petrol. (T/F)
Ans:-F
(c) Coke is almost pure form of carbon. (T/F)
Ans:-T
(d) Coal tar is a mixture of various substances. (T/F)
Ans:-T
(e) Kerosene is not a fossil fuel. (T/F)
Ans:-T

Ans:- Fossil fuels can be exhausted by human activities. Examples of these resources are forests, wildlife, minerals, coal, petroleum, natural gas etc.

Ans:- The characteristics of coke is, It is a tough, porous and black substance. It is almost pure form of carbon. Coke is used in the manufacture of steel and in the extraction of many metals.

Ans:- Petroleum is formed from organisms living in the sea. As these organisms died, their bodies settled at the bottom of the sea and got covered with layers of sand and clay. Over millions of years, absence of air, high temperature and high pressure transformed the dead organisms into petroleum and natural gas. And hence petroleum is formed.

Ans:- A chemical process in which a substance reacts with oxygen to give off heat is called combustion.

Ans:-The beaker which is kept in the outermost part will get heated in a shorter time because this part comes under complete combustion part.

(a) Burning of wood and coal causes of air.
Ans:- Burning of wood and coal causes Harmful gas of air.
(b) A liquid fuel, used in homes is .
Ans:- LPG, Kerosene oil
(c) Fuel must be heated to its before it starts
burning.
Ans:-Ignition temperature.
(d) Fire produced by oil cannot be controlled by .
Ans:-Water.

Ans:-The use of CNG in automobile, CNG is used for power generation. It is now being used
as a fuel for transport vehicles because it is less polluting. It is a cleaner fuel. Therefore we can say that CNG is used for reducing pollution in our country.

Ans:-LPG- It is a petroleum gas used in a liquid form. It is a inflammable substance, It is readily available. It is cheap. It burns easily in air at a moderate rate. It produces a large amount of heat. It does not leave behind any undesirable substances. While in case of wood It is not comes under a good fuel, it does not burns easily in air at moderate rate. Also it leaves undesirable substances after burning.

(a) Water is not used to control fires involving electrical equipment.
Ans:- The most common fire extinguisher is water. But water works only when things like wood and paper are on fire. Water is not used to control fires involving electrical equipment, electrical equipment is on fire, and water may conduct electricity and harm those trying to douse the fire. Water is also not suitable for fires involving oil and petrol.

(b) LPG is a better domestic fuel than wood.
Ans:-LPG is a better domestic fuel than wood, because It is cheap. It burns easily in air at a moderate rate. It produces a large amount of heat. It does not leave behind any undesirable substances. While in case of wood it is not a good fuel, it does not burns easily in air at moderate rate. Also it leaves undesirable substances after burning.

(c) Paper by itself catches fire easily whereas a piece of paper wrapped around an aluminium pipe does not.
Ans:-Paper is an inflammable substance because It has very low ignition temperature than a piece of paper wrapped around an aluminium pipe,.

Ans:- The calorific value of a fuel is expressed in a unit called kilojoule per kg (kJ/kg).

Ans:- Fires involving electrical equipment and inflammable materials like petrol, carbon dioxide (CO2) is the best extinguisher. CO2, being heavier than oxygen, covers the fire like a blanket. Since the contact between the fuel and oxygen is cut off, the fire is controlled. The added advantage of CO2 is that in most cases it does not harm the electrical equipment. It can be stored at high pressure as a liquid in cylinders. When Itreleased from the cylinder, CO2 expands enormously in volume and cools down.So, it not only forms a blanket around the fire, it also brings down the temperature of he fuel.

Ans:- As we know that a combustible substance cannot catch fire or burn as long as its
temperature is lower than its ignition temperature. Due to which it is difficult to burn a heap of green leaves than to dry leaves.

Ans:- Goldsmiths blow the outermost zone of a flame with a metallic blow-pipe for melting gold and silver.

Ans:-Calorific value(180,000/4.5)=40000kj/kg.

Ans:-No rusting process is different from combustion because rusting is carried out in presence of iron oxygen and water, while combustion process is carried out in presence of combustible substance. Combustion is a chemical process in which a substance reacts with oxygen to give off heat is called combustion.

Ans:a-Sanctuary.
b-Endemic
c-Climatic.

Ans:-a - Wildlife sanctuary- : Areas where animals are protected from any disturbance to them and their habitat. Biosphere is that part of the earth in which living organisms exist or which supports life. Biological diversity or biodiversity, refers to the variety of organisms existing on the earth, their interrelationships and their relationship with the environment.

b - Zoo- zoos are also places where animals receive protection. Wildlife sanctuary- : Areas here animals are protected from any disturbance to them and their habitat.

c - Endangered species are those which are facing the danger of extinction. A small animals are much more in danger of becoming extinct than the bigger animals And hence it is known as extinct species.

d - The plants and animals found in a particular area are termed flora and fauna of that area. Sal, teak, mango, jamun, silver ferns, arjun, etc are the flora. chinkara, blue-bull, barking deer, cheetal, leopard, wild dog, wolf, etc. are examples of the fauna.

Ans:- a - A great variety animals exists on earth. They are essential for the wellbeing and survival of animals. Today, a major threat to survival of these organisms is deforestation. Deforestation, effects as wild animals cannot live in the forests. Deforestation increases the temperature and pollution level on the earth. It increases the level of carbon dioxide in the atmosphere. Ground water level also gets lowered. They know that deforestation disturbs the balance in nature. Hence we can say that wild animals life fully effected by deforestation.

b - Today, a major threat to survival of these organisms is deforestation. We know
that deforestation means clearing of forests. Deforestation increases the temperature and pollution level on the earth. It increases the level of carbon dioxide in the atmosphere. Ground water level also gets lowered. They know that deforestation disturbs the balance in nature. If cutting of trees continues, rainfall and the fertility of the soil will decrease. So there will be increased chances of natural calamities such as floods and droughts.

c - The increase in temperature on the earth disturbs the water cycle and may reduce
rainfall. This could cause flood and droughts. Deforestation is a major cause which
leads to the change in soil properties. Physical properties of the soil get affected by plantation and vegetation. So that Deforestation effects villages.

d - Deforestation increases the temperature and pollution level on the earth. It increases the level of carbon dioxide in the atmosphere. Ground water level also gets lowered. They know that deforestation disturbs the balance in nature of urban areas.

e - A great variety of plants and animals exists on earth. They are essential for
the wellbeing and survival of mankind. Today, a major threat to survival of these
organisms is deforestation. Deforestation means clearing of forests and using that land for other purposes. Trees in the forest are cut for some of the purposes mentioned below:
_ Procuring land for cultivation.
_ Building houses and factories.
_ Making furniture or using wood as fuel.
Deforestation increases the temperature and pollution level on the earth. It increases the level of carbon dioxide in the atmosphere. Ground water level also gets lowered. They know that deforestation disturbs the balance in nature. If cutting of trees continues, rainfall and the fertility of the soil will decrease. So there will be increased chances of natural calamities such as floods and droughts. Hence the earth will too much affected by deforestation.

f - There will be a large effect of deforestation on next generation because due to this our coming generation will cannot survive easily due to lack of forests. They will be not able to take fresh air. If we have to retain our green wealth for generations, plantation of more trees is the only option.

Ans: a - Cutting of trees leads to deforestation which is quite harmful to the environment, cutting of trees continues, rainfall and the fertility of the soil will decrease.

b - When the habitat of an animal is disturbed the destruction of their habitat, increasing population and introduction of new species may affect the natural habitat of endemic species and endanger their existence.

c - Removal of the top layer of the soil exposes the lower, hard and rocky layers. This soil has less humus and is less fertile. Gradually the fertile land ets converted into deserts. It is called desertification.

Ans:- a - Biological diversity or biodiversity, refers to the variety of organisms existing on the earth, their interrelationships and their relationship with the environment. Biosphere reserves are the areas meant for conservation of biodiversity. The biosphere reserves help to maintain the biodiversity and culture of that area. A biosphere reserve may also contain other protected areas in it.

b - There are various factors disturbing the biodiversity of our area, protected forests. Some of these factors and human activities may disturb the biodiversity unknowingly. So that protected forests are also not completely safe for wild animals.

c - Some tribal depends on the jungle can be understand by this way is that, Rock shelters are also found inside the Satpura National Park. These are the prehistoric evidences of human life in these jungles. They give us an idea of the life of the primitive people. Rock paintings are found in these
shelters. A total of 55 rock shelters have been identified in Pachmarhi Biosphere Reserve.
Figures of animals and men fighting, hunting, dancing, and playing musical instruments are depicted in these paintings.

d - We know that cause of deforestation means clearing of forests and using that land for other purposes. Trees in the forest are cut for some of the purposes mentioned below:
_ Procuring land for cultivation.
_ Building houses and factories.
_ Making furniture or using wood as fuel.
While consequences of deforestation is that deforestation increases the temperature and pollution level on the earth. It increases the level of carbon dioxide in the atmosphere. Ground water level also gets lowered. They know that deforestation disturbs the balance in nature.

e - Red Data Book is the source book which keeps a record of all the endangered animals and plants. There are different Red Data Books for plants, animals and other species.

f - Migration is known as in terms that , migratory birds fly to far away areas every year during a particular time because of climatic changes. They fly for laying eggs as the weather in their natural habitat becomes very cold and inhospitable. Such condition is known as migration.

Ans:- Green wealth for our locality can be done by plantation of more trees is the only
option. So our aimed at preservation and conservation of natural forests and meeting the basic needs of the people living in our locality.

Ans:- Deforestation increases the temperature and pollution level on the earth. It increases the level of carbon dioxide in the atmosphere. Ground water level also gets lowered. Deforestation disturbs the balance in nature. So that if cutting of trees continues, rainfall and the fertility of the soil will decrease. Hence in this way deforestation leads to reduce rainfall.

Ans:- As we know that paper is one of the important products which we get from forests. Therefore we should save the paper. We can save paper by avoiding the cutting of trees as bamboo trees.

Ans: (a) Unicellular organisms have one-celled body. (T/F)
Ans:-T
(b) Muscle cells are branched. (T/F)
Ans:-F
(c) The basic living unit of an organism is an organ. (T/F)
Ans:-F
(d) Amoeba has irregular shape. (T/F)
Ans:-T

(a) Cytoplasm
Ans:- It is the jelly-like substance present between the cell membrane and the nucleus. Various other components, or organelles, of cells are present in the cytoplasm. These are mitochondria, golgi bodies, ribosomes, etc.

(b) Nucleus of a cell
Ans:- It is an important component of the living cell. It is generally spherical and located in the centre of the cell. It can be stained and seen easily with the help of a microscope. Nucleus is separated from the cytoplasm by a membrane called the nuclear membrane. This membrane is also porous and allows the movement of materials between the
cytoplasm and the inside of the nucleus.

Ans:- cytoplasm is a part of the cell which consists organelles.

Ans:-The three differences between the plant cells and animal cells are as given ,
1.plant cell consists cell walls while animal cell does not consists it
2. plant cell consists vacuole which is large in size. while animal cell consists vacuole which is small in size.
3. Coloured bodies called plastids are found in the plant cells only while animal cell does not consists it.

Ans:- The cells having nuclear material without nuclear membrane are termed prokaryotic
cells. The organisms with these kinds of cells are called prokaryotes. While, The cells, having well organised nucleus with a nuclear membrane are designated as eukaryotic cells. All organisms other than bacteria and blue green algae are called eukaryotes.

Ans:-Chromosomes found in a nucleus, as it contains thread-like structures called chromosomes. Here the functions of chromosomes are, These carry genes and
help in inheritance or transfer of characters from the parents to the offspring. The chromosomes can be seen only when the cell divides.

Ans:- Organs are made of still smaller parts. The smallest living part of an organism is a ‘cell’.
_ Cells were first observed in cork by Robert Hooke in 1665.
_ Cells exhibit variety of shapes and sizes.
_ Number of cells also varies from organism to organism.
_ Some cells are big enough to be seen with the unaided eye. Hen’s egg is an example.
_ Some organisms are single-celled, while others contain large number of cells.
_ The single cell of unicellular organisms performs all the basic functions performed by a variety of cells in multicellular organisms.
_ The cell has three main parts,
(i) the cell membrane, (ii) cytoplasm which contains smaller components called organelles, and (iii)
the nucleus. Cells sometimes are quite long. Some are branched like the nerve cell or a neuron.The nerve cell receives and transfers messages, thereby helping to control and coordinate the working of different parts of the body. The change in shape is due to formation of pseudopodia which facilitates movement and help in capturing food. Thus cells are the basic structural unit of living organisms.

Ans:- Several small coloured bodies in the cytoplasm of the cells of Tradescantia leaf. They are scattered in the cytoplasm of the leaf cells. These are called plastids. They are of different colours. Some of them contain green pigment called chlorophyll. Green coloured plastids are called chloroplasts. They provide green colour to the leaves. chlorophyll in the chloroplasts of leaves, is essential for photosynthesis. Therefore chloroplasts are found only in plant cell.