Question Discussion & Solution

The correct answer is chemical energy.

Key Points

• The dry cell is a type of electric battery which is used for portable electrical devices.
• Electricity is produced through the dry cells from electrochemical energy. Hence, Option 1 is correct.
• A common dry cell is a zinc-carbon cell.
• The electrolyte is immobilized as a paste by a dry cell, with just enough humidity in it to allow current to flow.
• Like a wet cell, a dry cell can work without spilling in any direction, because there is no free liquid in it.
• The versatility makes it ideal for mobile devices.
• The first wet-cell batteries, in comparison, were usually fragile glass containers featuring lead rods sticking from an open-top.
• Hence, they required careful handling to prevent spillage.
• The dry-cell battery development made a significant advance in battery safety and portability.
• Batteries render electricity from chemical energy.
• Batteries consist of one or more different parts, or cells, which contain an electrolyte called a chemical.
• Every cell has two electrodes that are electrically conductive immersed in its electrolyte.
• The electrodes consist of different materials; one releases electrons into the electrolyte, and the other absorbs them.
• Once an electrical system is attached to the electrodes, an electrical current passes through it and supports its operation with electric power.
• The energy contained in the dry cell is therefore in the form of chemical energy.

Additional Information

• Thermal energy
  • It is also called heat energy 
  • It is produced when a rise in temperature causes atoms and molecules to move faster and collide with each other.
  • The energy that comes from the temperature of the heated substance is called thermal energy.
  • Thermal energy is energy that comes from a substance whose molecules and atoms are vibrating faster due to a temperature rise.
• In physical sciences, mechanical energy
  • It is the sum of potential energy and kinetic energy.
  • It is the macroscopic energy associated with a system.
  • The principle of conservation of mechanical energy states that if an isolated system is subject only to conservative forces, then the mechanical energy is constant.
• Nuclear power
  • It is the use of nuclear reactions to produce electricity.
  • Nuclear power can be obtained from nuclear fission, nuclear decay, and nuclear fusion reactions.
  • Presently, the vast majority of electricity from nuclear power is produced by nuclear fission of uranium and plutonium in nuclear power plants.

The correct answer is China.

Key Points

• The Russia and China joint naval exercises “Joint Sea 2021” has kicked off at Russia’s Peter the Great Gulf, in the Sea of Japan, on October 14, 2021.
• The exercises will culminate on October 17, 2021.
• The drill is being carried out as part of ‘Joint Sea’ 2021, the series of bilateral naval exercises that have been taking place between the two services since 2012.

Additional Information

•  Important Exercises between India and other countries:

In the mixed series, the letter added 2 and number added 12 we get-

 Hence, "76" is the correct answer.

Concept:-

• Plants have diverse varieties.
• There are more than 3 lakh plants species that have already been found in the world.
• Plants are beneficial in human life they give food, shelter and fulfil many other needs of various organisms.

Explanation:-

Bryophytes:

• Bryophytes are often referred to as the amphibians of the plant kingdom.
• Bryophytes are small, non-vascular plants.
• The reproduction of Bryophytes is via spores.
• Bryophytes are live in the soil, even though they need water for sexual reproduction this is the reason why the Bryophytes are often referred to as the amphibians of the plant kingdom.
• Bryophytes are generally classified into three coordinate phyla namely the liverworts, hornworts, and mosses.
• The following division, bryophytes, were the first land occupying or inhabiting plants.
• They fill in sodden or damp regions since they require water for fertilization.
• Consequently, they are called the creatures of land and water of the plant kingdom or the amphibians of the plant kingdom.

Thus, the first plants to inhabit the land are Bryophytes.

Additional Information 

Kingdom plants are divided into five groups- Thallophytes, Bryophytes, Pteridophytes, Gymnosperms, and Angiosperms.

Thallophyta

• The plant body is not differentiated from roots, stems, and leaves.
• They are commonly called algae.

Bryophyta

• These are small terrestrial plants.
• They show differentiation in the body design, with stem, leaf-like structures, and root-like structures.

Pteridophyta

• The plant body is differentiated into roots, stems, and leaves, apart from having a specialized tissue for conduction.

Gymnosperms

• Gymnosperms are plants with naked seeds.

Angiosperms

• Angiosperms are seed-bearing plants. Seeds develop inside tissues that get modified to form the fruit of the plant. 

The correct answer is Rice.

• Rice blast disease, caused by Magnaporthe oryzae (Ascomycota), occurs in about 80 countries on all continents where rice is grown, in both paddy fields and upland cultivation.
• The extent of damage caused depends on environmental factors, but worldwide it is one of the most devastating cereal diseases, resulting in losses of 10–30% of the global yield of rice.
• Other common diseases of the crop of rice are - Blight, Bacterial leaf streak, Brown spot, Sheath blight, False smut, etc.

Additional Information

• The biological agents that causing diseases to plants are known as pathogens. 
• Some of the viral diseases in plants are - bud blight (soyabeans), Curly tops (Beans, tomato, etc.), Mosaic leaf (Tomato, pea, potato,tobacco, etc.).
• Some of the bacterial diseases in plants are - Blights (vegetable crops), Bacterial wilts (Tobacco, potatoes, etc), Cankers (Woody plants), Leaf Spots, Soft Wrots, etc.
• Some of the fungal diseases in the plants are - Cankers, Ergot, Rusts, Root rots, Scabs, Smuts, etc.