6th Science 1st Term Revision Test in English – New Book

Explanation: Length is a fundamental quantity. That means, it connot be expressed in anyother quantities. Using length, we can find out other measurements like Area and Volume so they are derived quantities.

Explanation: Measuring the volume of a liquid is quite easy. Liquids take the shape of the container in which they are kept. A liquid whose volume is to be found can simply be poured into a graduated container. Graduated cylinders, beakers, pipettes and burettes are available for measuring exact volumes. The volume of liquid is usually measured in litres

Explanation: SI unit for Volume of solid is cubic metre. Liquids and gases are usually measured in litres. But also can be measured in m3 or cubic metre.

Explanation: The weight is directly proportional to the mass on earths surface. On moon where the gravitational force is lesser than earth, the weight will reduce but the mass will remain same. The moon’s gravitational pull is one sixth of the earth’s pull. Thus objects weigh six times lighter on the Moon than on the Earth.

Explanation: An odometer is a device used for indicating distance travelled by an automobile.

Explanation: A standard metre rod made of an alloy of platinum and iridium is placed at the Bureau of weights and measures in Paris. National Physical Laboratory in Delhi has a copy of this metre rod.

Explanation: Besides solids, Liquid and gases there are two more states plasma and Bose – Einstein condensates. Bose – Einstein condensate is a gas – like state of matter that exists at extremely cold temperatures. It was predicted around 1925 and confirmed in 1995, This is used in the field of cryogenics

Explanation: Purity of gold is expressed in terms of ‘carat’. 24 carat gold is considered to be gold in its purest form.

Explanation: Diffusion is the tendency of particles to spread out in order to occupy the available space.

Explanation: The metric system or standard set of units was created by the French in 1790.

Explanation: One kilogram is equal to the mass of a certain bar of platinum-iridium alloy that has been kept since 1889 at the International Bureau of Weights and Measures in Sèvres, France.

Explanation: Physical quantity can be measured.

Explanation: Forces can be classified into two major types; contact and non-contact forces. Wind is making a flag flutter, a cart pulled by a bullock are contact forces. Magnetism, gravity are some examples of non-contact forces.

Explanation: All oscillatory motions are periodic, but not all periodic are oscillatory.Revolution of the moon around the earth is periodic but not oscillatory. However, the children playing in a swing is both periodic and oscillatory.

Explanation: Oscillatory motion is coming back to the same position after a fixed time interval, like a pendulum.

Explanation: Magnetism is a type of a Non contact force

Explanation: Circular Motion is based on path whereas Periodic and Non periodic motions are based on duration and Uniform motion is based on Speed.

Explanation: A drop of water contains about 10^21 water particles.

Explanation: The particles in matter are extremely small and cannot be seen even with a powerful microscope.Particles of matter have lot of space in between them. Particles of matter attract each other. Gold is made up of tiny gold particles.

Explanation: When very fine insoluble solids have to be separated from a liquid as in butter from curds, Churning is performed. The mixture is churned vigorously when solid butter will be collected on the sides of the vessel. Both butter and buttermilk are obtained after churning are useful and can be consumed.

Explanation: In washing machines this principle is used to squeeze out dirt from clothes and the method is called centrifugation.

Explanation: Separating solids using a magnet is called magnetic separation.

Explanation: The water with the impurities is carefully poured away leaving clean rice at the bottom. This is called decantation. SEPARATING MUD FROM MUDDY WATER” uses the Method of decantation.

Explanation: Filtration –Process of separating insoluble solid particles (residue) from a liquid (filtrate) by using a filter paper.

Explanation: Liquid atoms are packed more loosely which allows things to be able to pass through it 2. Liquid is effected by gravity more than anything. A gas atoms are spread out so far, you can walk through it without any restriction 2. Gas is not affected by gravity.

Explanation : “Liquefaction of gases” is the process by which substances in their gaseous state are converted to the liquid state. When pressure on a gas in increased, its molecules comes closer together, and its temperature is reduced, which removes enough energy to make it change from the gaseous to the liquid state.

Explanation: Liquids have No definite shape, liquids attain the shape of the vessel in which they are kept. The force of attraction between liquid particles is less than solid particles.

Explanation: Rice, wheat and other food grains are covered in husk which cannot be eaten by us. Husk is very light and gets easily blown away by a breeze or wind. This property is Winnowing.

Explanation: It consists of a single root, called taproot, which grows straight down into the ground. Smaller roots, called lateral roots arise from the taproot. They are seen in dicotyledonous plants. Example: Bean, Mango, Neem.

Explanation: A leaf has a stalk called petiole. The flat portion of the leaf is called leaf lamina or leaf blade. On the lamina, there is a main vein called midrib.

Explanation: The green colour of the leaf is due to the presence of green coloured pigment called chlorophyll. On the lower side of the leaf there are tiny pores or openings known as stomata. Explanation: The green colour of the leaf is due to the presence of green coloured pigment called chlorophyll. On the lower side of the leaf there are tiny pores or openings known as stomata.

Explanation: Victoria amazonica, the leaves of this plant grow up to 3 metres across. A mature Victoria leaf can support an evenly distributed Load of 45 Kilograms or apparently young person.

Explanation:  Nile is the longest river in the world. It is 6650 Km long. The Longest river in India is Ganges River. It is 2525 Km long.

Explanation: Air spaces in stems and petioles of lotus are useful for floating in water.

Explanation: Marine plants perform about 40% of all photosynthesis that occurs on the planet. Example: Marine Algae, Sea grasses, Marsh grass, Phytoplanktons.

Explanation: Stem and leaves have air chambers that allow aquatic plants to float in water.

Explanation: The Amazon Rain Forest in South America produces half of the world’s oxygen supply.

Explanation: World habitat day is observed on 1st Monday of October.

Explanation: Tendril is a twining climbing organ of some weak stemmed plants like peas and bitter gourd. Tendril coils round a support and help the plant to climb. Example: 1. Sweet Peas Leaflets are modified into tendrils

Explanation: When stomata are open, transpiration rates increase; when they are closed, transpiration rates decrease. It helps in transpiration.

Explanation: The Water Hyacinth has a Aquatic Habitat.

Explanation: Bryophyllum is a Example of Plants having long roots that go very deep in the soil in the search of water. They are found in deserts.

Explanation: Twiners:- Some plants have weak stems. They cannot stand straight on their own. They must climb on any support to survive. Example: Clitoria and Jasmine.

Explanation: Amoeba, Paramecium and Euglena are unicellular while, fish, frog, lizard, bird and man are multicellular.

Explanation: Thorns:- Leaves of some plants become wholly or partially modified into sharp pointed structures called “thorns or spines” for defensive purpose. Example: 1. Agave - the leaf apex and margins are modified into thorns 2. Opuntia - the leaves are modified into spines. 3. bougainvillea – the stem has sharp thorns.

Explanation: The fish has special organs called “Gills” which is a respiratory organ helps to absorb oxygen dissolved in water for breathing. It is adapted to breathe in water.

Explanation: Unicellular organisms are made up of single cell. Growth in unicellular occurs by an increase in the size of the cell Growth in Multicellular organism occurs by an increase in the number of cells by cell division.

Explanation: Amoeba’s have finger-like structures called Pseudopodia, (false foot) which help in movement or locomotion.

Explanation: RO – a process of removing impurities from water to make it potable.

Explanation: 1 metre is equal to 1000000000 nano metre.

Explanation: Bose – Einstein condensate is a gas – like state of matter that exists at extremely cold temperatures. It was predicted around 1925 and confirmed in 1995, This is used in the field of cryogenics.

Explanation: km > m > cm > mm

Explanation: Mass is the measure of the amount of matter in an object. Weight is the gravitational pull experienced by the mass.

Explanation: The objects weigh six times lighter on the Moon than on the Earth.

Explanation: Volume of irregular objects can be measured by water displacement method.

Explanation: Objects in Gaseous state is Highly compressible.

Explanation: A Mixture is an impure substance and contains more than one kind of particles. • In the mixture the components are mixed in any proportion.

Explanation: The process by which the components of mixture are isolated and removed from each other to get pure substance is called separation.

Explanation: Adulteration – make impure by the addition of a foreign or inferior substance.

Explanation: Based on position of sead: Plants can be divided into two groups. Angiosperms. and Gymnosperms

Explanation: Phytoplanktons are example of Marine habitat system.

Explanation: in Amoeba Contractile vacuoles help in excretion. Respiration is by simple diffusion through the body surface.

Explanation: Euglena is an unicellular animal which moves with a flagellum.

Explanation: Earthworms, Fish, Frogs, Lizard and human beings etc are Multicellular organisms

Explanation: When an animal moves its location as the season changes it is said to be Migration

Explanation: Spending winters in a dormant condition is called Hibernation. eg. Turtle

Explanation: Spending the hot and dry period in an inactive state is known as Aestivation. eg. Snail.

Explanation: Study of life and living things is called biology. Scientists who study biology are known as biologists.

Explanation: A camel’s hump has fat stored in it. In case of emergency a camel can break down stored fat for nourishment.

Explanation: There are six major vitamins A, B, C, D, E and K. Vitamins B and Vitamins C are water soluble, Vitamins A, D, E and K are fat soluble.

Explanation: There are six major vitamins A, B, C, D, E and K. Vitamins B and Vitamins C are water soluble, Vitamins A, D, E and K are fat soluble.

Explanation: Deficiency of Vitamin B causes Beri Beri.

Explanation: Vitamin D helps in Calcium absorbtion and strong bones.

Explanation: Deficiency in Vitamin A can cause Night Blindness.

Explanation: Vitamin C is found in Oranges, Gooseberry, Greenchilly, Tomatoes etc.

Explanation: Gooseberries contains nearly 20 times the vitamin C than Orange.

Explanation: Calcium- Strong bones and teeth, clotting of blood Phosphorus- Strong bones and teeth Iodine -Synthesis of thyroid hormone Iron- Formation of haemoglobin and brain development.

Explanation: Kwashiorkar- Stunted growth, Swelling of face and limbs, Diarrhoea. Marasmus- Skinny appearance, Slow body growth.

Explanation: Iodine deficiency -Cretinism (in Child) Goitre (in adult)

Explanation: Goitre occurs only in adults.

Explanation: India has the second highest number of obese children in the world after China, according to a study that has found that 14.4 million children in the country have excess weight.

Explanation: Diseases Caused By Virus 1. Common cold 2. Influenza 3. Hepatitis 4. Polio 5. Smallpox 6. Chicken pox 7. Measles.

Explanation: Typhoid- contaminated food or water.

Explanation: Bacteria is a Prokaryotic microorganism.

Explanation: Bitter Gourd - Axillary buds are modified into tendril which helps the plant to climb.

Explanation: In Jurong Birds Park, Singapore, Penguins are kept in a big glass case with ice bergs and temperature is maintained at 0° C and below

Explanation: A Cheetah is the fastest land animal running with an average speed of 112 km/h.

Explanation: The term comes from a czech word, ‘robota’ meaning ‘forced labour’. Robotics is the science and study of robots.

Explanation: Science has come up with a technology to identify structure of atoms Scanning Electron Microscope (SEM) and Tunnelling Electron Microscope (TEM) which uses electricity to map atoms.

Explanation: Plasma is not a common state of matter on Earth, but may be the most common state of matter in the universe. For example, stars including sun are covered in plasma.

Explanation: Separating clear supermatant without disturbing sediment is done by decantation

Explanation: Turmeric powder is adulterated with a bright yellow chemical which is poisonous to our health.

Explanation: Fibrous root system consists of a cluster of roots arising from the base of the stem. They are thin and uniform in size. It is generally seen in monocotyledonous plants. Example: Grass, Paddy, Maize.

Explanation: The bud at the tip of the stem is known as apical or terminal bud.

Explanation: On the lamina, there is a main vein called midrib. Other veins are branchout from mid rib.

Explanation: The first land plants appeared around 470 million years ago. They were mosses and liverworts.

Explanation: Thar Desert, also called Great Indian Desert, is an arid region of rolling sand hills on the Indian subcontinent. It is located partly in Rajasthan state, north-western India, and partly in Punjab and Sindh (Sind) provinces, eastern Pakistan.

Explanation: The volume of liquid is usually measured in litres.