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All questions of Class 6 for UPSC CSE Exam

Can you explain the answer of this question below:

Green plants prepare their own food, hence they are called as

  • A:

    Decomposers

  • B:

    Autotrophs

  • C:

    Parasites

  • D:

    Heterotrophs

The answer is b.

Kunal Das answered
Green plants have the ability to prepare their own food and this is the reason why they are called autotrophs. 
The chlorophyll which is present in the leaves is the main reason for the production of food in the plants and it is the reason for the greenery of the leaves too.

Which one is not a function of food:
  • a)
    Repair body parts
  • b)
    Gives us energy
  • c)
    Help in growth
  • d)
    Prepare protein
Correct answer is 'D'. Can you explain this answer?

Sneha Jha answered
As we all know that food help us to repair the damage part of our body, Gives us food, Help in growth. But as we know that protein is synthesis in our body not prepare.

Which one of the following is not an example of natural fibre?
  • a)
    Rayon
  • b)
    Cotton
  • c)
    Wool
  • d)
    Silk
Correct answer is option 'A'. Can you explain this answer?

Rithika Roy answered
Silk, cotton and wood are obtained from natural sources either plant or animal but rayon is a synthetic fibre.

Q.Silkworms feeds on leaves of
a)Guava
b)Mulberry
c)Banana
d)Mango
Correct answer is option 'B'. Can you explain this answer?

Kavya Rane answered
Silkworms can ONLY survive on mulberry leaves (genus Morus), sometimes Osage orange (Maclura pomifera) or silkworm food, which is made from mulberry leaves. Your worms may eat other types of vegetation, such as lettuce leaves, but it will kill them.

Curd is formed by the action of
  • a)
    Protozoa
  • b)
    Bacteria
  • c)
    Fungus
  • d)
    Algae
Correct answer is option 'B'. Can you explain this answer?

Rajesh Khatri answered
The increased acidity causes the milk proteins (casein) to tangle into solid masses, or curds. Milk that has been left to sour (raw milk alone or pasteurized milk with added lactic acid bacteria) will also naturally produce curds, and sour milk cheeses are produced this way.

Pulses are rich source of
  • a)
    Minerals
  • b)
    Roughages
  • c)
    Proteins
  • d)
    Fibre
Correct answer is 'C'. Can you explain this answer?

Aruna Singh answered
Pulses are a low fat source of protein with high levels of protein and fibre. 
Pulses also contain important vitamins and minerals like iron, potassium and folate.

Choose the opaque materials form the following
  • a)
    Thin sheet of plastic
  • b)
    Glass container.
  • c)
    Wooden door
  • d)
    Clear water
Correct answer is 'C'. Can you explain this answer?

Wooden door is an opaque object as it has all the properties of one:
1. Opaque materials are those through which light cannot pass at all.
2. We cannot see through these objects. They can also be called not-see-through objects.
3. The color of this material depends on the light it absorbs.
4. An object on the other side of this material is not visible at all.

Spices provide
  • a)
    Flavour
     
  • b)
    Vitamins
  • c)
    Energy
  • d)
    Proteins
Correct answer is 'A'. Can you explain this answer?

Allspice is pungent and fragrant. It is not a blend of "all spices," but its taste and aroma remind many people of a mix of cloves, cinnamon, and nutmeg. Christopher Columbus discovered Allspice in the Caribbean. Although he was seeking pepper, he had never actually seen real pepper and he thought Allspice was it.

Q. The movement of earth around the sun is an example of
a)Oscillatory motion
b)Circular motion
c)Translatory motion
d)Periodic motion
Correct answer is 'D'. Can you explain this answer?

Rajesh Khatri answered
The answer is b.
A body moving along a circular pat is said to have a circular motion.
The distance of the moving body remains constant from a fixed point or axis, called the axis of rotation. The moving body changes its position during the motion. Thus the  movement of earth around the sun is an example of Circular motion.

Pollen grains are produced in side
  • a)
    Ovary
  • b)
    Stigma
  • c)
    Anther
  • d)
    Pistil
Correct answer is option 'C'. Can you explain this answer?

Alok Verma answered
The male sex cells of seed plants (flowering plants, conifers, and cycads) are contained in tough capsules called POLLEN. Pollen grains are produced by organs called anthers and must be transferred to the female parts of plants in order to form seeds. This process, called pollination, can be achieved in various ways. Some plants are assisted by animals that act as POLLINATORS. Others use the wind to take their pollen where it is needed.

Chemical changes are
  • a)
    Mostly reversible
  • b)
    Always irreversible
  • c)
    Always reversible
  • d)
    Mostly irreversible
Correct answer is option 'D'. Can you explain this answer?

Kiran Mehta answered
Chemical changes are changes that occur in the chemical properties of the substance like its flammability, radioactivity, etc. All chemical changes are mostly irreversible changes. Once the chemical properties of a substance are changed, it becomes another substance. Thus, it cannot return to its original state in most cases.

Silk thread is obtained from
  • a)
    Cocoon
  • b)
    Caterpillar
  • c)
    Pupa
  • d)
    Adult moth
Correct answer is option 'A'. Can you explain this answer?

Meera Reddy answered
The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the cocoons of the larvae of the mulberry silkworm Bombyx mori reared in captivity (sericulture).

Select the translucent materials from the following?
  • a)
    Glass tumbler
  • b)
    Aluminium foil
  • c)
    Muslin cloth
  • d)
    Mirror
Correct answer is 'C'. Can you explain this answer?

Anjali Kapoor answered
Muslin cloth is the example of translucent cloth while tericot is the example of opaque cloth material. Any material which will be completely transparent will not be used as cloth material.

Which one is not a transparent object?
  • a)
    Clean water
  • b)
    Glass
  • c)
    Thin sheet of plastic
  • d)
    Muddy water
Correct answer is option 'D'. Can you explain this answer?

Charvi Sen answered
The object through which light passes easily are called as transparent object. Clean glass, glass and thin sheet of plastic are transparent while muddy water is translucent.

Which one is not a natural source of water
  • a)
    River
  • b)
    Lake
  • c)
    Canal
  • d)
    Pond
Correct answer is option 'A'. Can you explain this answer?

Kunal Mehta answered
Correct option is (c) .
Dams, wells, tube wells, hand-pumps, canals, etc, are man-made sources of water. 

Digestion of food is a
  • a)
    Temporary change
  • b)
    Periodic change
  • c)
    Chemical change
  • d)
    Physical change
Correct answer is option 'C'. Can you explain this answer?

Aarya Joshi answered
Digestion of food is a chemical change as chemical action change takes place to break the complex food into simpler substance by action of enzymes.

Which mineral is primarily responsible for the formation of haemoglobin in the blood?
  • a)
    Calcium
  • b)
    Phosphorus
  • c)
    Iron
  • d)
    Iodine
Correct answer is option 'C'. Can you explain this answer?

Dr Manju Sen answered
Iron is crucial for the formation of haemoglobin, the protein in red blood cells responsible for transporting oxygen from the lungs to tissues throughout the body. Without sufficient iron, the body cannot produce an adequate amount of healthy red blood cells, leading to a condition known as iron-deficiency anemia. Including iron-rich foods in the diet is essential for maintaining healthy levels of haemoglobin in the blood.

All metals are ----------- of heat and electricity.
  • a)
    Insulator
  • b)
    Semi-conductor
  • c)
    Good conductor
  • d)
    Bad conductor
Correct answer is option 'C'. Can you explain this answer?

Kunal Mehta answered
In metals, some of the electrons (often one per atom) are not stuck to individual atoms but flow freely among the atoms. Of course, that's why metals are such good conductors of electricity.

Explain the following observations briefly:
An empty glass in fact is not empty.
  • a)
    Filled with water 
  • b)
    Filled with air
  • c)
    Not empty
  • d)
    Empty
Correct answer is option 'B'. Can you explain this answer?

Anita Menon answered
The glass which is empty is actually filled with air. And because air takes up space when an empty glass is inverted and inserted into a trough filled with water, the air is trapped within and it is no anyway for air to escape out.

Which among the following materials are not lustrous
  • a)
    Silver
  • b)
    Gold
  • c)
    Diamond
  • d)
    Wood
Correct answer is option 'D'. Can you explain this answer?

Pritam Shah answered
Those substances that have shining surface are called as lustrous substance. Diamond, gold and silver are lustrous

Can you explain the answer of this question below:

Which type of material is used to make wind screen of a car?

  • A:

    Transparent

  • B:

    Translucent

  • C:

    Opaque

  • D:

    Semi-transparent

The answer is A.

Bijoy Goyal answered
Material Used to Make Windscreen of a Car

The windscreen of a car is an essential component that protects the driver and passengers from wind, rain, dust, and other external elements. It is a transparent screen made of a special type of material that provides excellent visibility to the driver. The material used to make the windscreen of a car is:

Transparent

Transparent materials allow light to pass through them without scattering the light. The windscreen of a car is made of transparent materials such as glass, polycarbonate, or acrylic. The choice of material depends on the manufacturer's preference and the type of car. Glass is commonly used in high-end cars, while polycarbonate and acrylic are used in budget cars.

Glass

Glass is a brittle and transparent material made by melting silica with other materials. The glass used in car windscreens is tempered glass, which is heated and cooled rapidly to make it stronger and more durable. Tempered glass is resistant to impact and shattering, making it an ideal material for car windscreens.

Polycarbonate

Polycarbonate is a transparent and lightweight thermoplastic material that is commonly used in car windscreens. It is highly resistant to impact, shattering, and UV radiation, making it an excellent material for car windscreens. Polycarbonate is also more flexible than glass, making it less prone to cracking or breaking.

Acrylic

Acrylic is a transparent thermoplastic material that is commonly used in budget cars. It is less expensive than glass and polycarbonate, making it an affordable option for car windscreens. However, acrylic is less durable than glass and polycarbonate and is more prone to scratching and cracking.

Conclusion

In conclusion, the material used to make the windscreen of a car is transparent. Glass, polycarbonate, and acrylic are the most commonly used materials for car windscreens. The choice of material depends on the manufacturer's preference and the type of car.

Which of the following substance is found in all three states in nature?
  • a)
    Ether
  • b)
    Water
  • c)
    Petrol
  • d)
    Kerosene oil
Correct answer is option 'B'. Can you explain this answer?

Varun Kapoor answered
Water is the only substance on Earth that is present in all three states of matter – as a solid, liquid or gas. (And Earth is the only planet where water is abundantly present in all three states.

Snail moves with the help of
  • a)
    Whole body
  • b)
    Bone
  • c)
    Shell
  • d)
    Muscular foot
Correct answer is option 'D'. Can you explain this answer?

Arjun Desai answered
A snail uses its single long, muscular foot to crawl on a layer of mucus-like slime that it secretes. ... The waves move much faster than the snail itself, and generate enough force to push the snail forward.

In general, on heating metals _______
  • a)
    contract
  • b)
    expand
  • c)
    can expand or contract
  • d)
    none of these
Correct answer is option 'B'. Can you explain this answer?

When a metal ring is heated, does the hole expand, contract, or stay the same size? Spoiler alert: The puzzle is answered in the update at the end of this post. Most solids expand when heated and contract when cooled. Water/ice is anomalous in that it expands when cooled, at least near its freezing point.

The joint which helps in rotating a body in all directions is called _______
  • a)
    Hinge joint
  • b)
    Ball and Socket Joint
  • c)
    Pivot joint
  • d)
    Fixed Joint
Correct answer is option 'B'. Can you explain this answer?

Shaila Patel answered
The ball and socket joint, the bones can be turned in any direction i.e. forward and backward, side to side and even rotated. The ball and socket joints occur at the shoulder and hips in our body.

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