General Quiz Preparation

The state of matter of a substance can be changed by manipulating its temperature and pressure.

Solids have their particles tightly packed together, resulting in a fixed shape and volume.

Gases are easily compressible because their particles are spread out and weakly attracted to each other. They have no fixed shape or volume.

Metals conduct heat and electricity well, are malleable (can be hammered into thin sheets), and ductile (can be drawn into wires).

Metalloids possess properties that bridge the gap between metals and nonmetals. They are semi-conductors, meaning they conduct electricity under specific conditions.

Sublimation is a direct phase change from solid to gas without going through the liquid state.

Tincture of iodine is a Solution of iodine in ethanol, often used as an antiseptic.

Bromine is a liquid nonmetal at room temperature, while carbon is a solid nonmetal. Both are important elements in various compounds.

Mixtures are composed of two or more pure substances, and heterogeneous mixtures have visible boundaries between their components.

Suspensions are heterogeneous mixtures with particles that do not dissolve but remain suspended, making them easily distinguishable from solutions.

Centrifugation is a technique that utilizes density differences to separate components, like separating butter from curd. Evaporation is used to separate salt from seawater through the vaporization of water.

Chemical changes involve the formation of new substances with different properties than the original substances.

A colloid is a mixture with particle sizes between solutions and suspensions. They exhibit the Tyndall effect, scattering light beams.

Salt solution does not exhibit the Tyndall effect. Milk, a colloidal solution, shows the Tyndall effect because its particles scatter light.

A chemical substance always contains elements in definite proportions by mass, and atoms are indivisible and cannot be created or destroyed during chemical reactions.

A molecule consists of two or more atoms bonded together. Atoms of the same or different elements can combine to form molecules.

The atomicity of a molecule refers to the number of atoms present in the molecule.

Negatively charged ions are called anions, while positively charged ions are called cations.

Rutherford's atomic model, based on his gold foil experiment, proposed a positively charged nucleus at the center of an atom, orbited by negatively charged electrons. However, it could not explain the stability of the atom, an idea developed later by Niels Bohr.

Chadwick discovered the neutron, a neutral subatomic particle found within the nucleus of an atom. All atoms except hydrogen contain neutrons.

Electrons in an atom are arranged in different energy levels called shells or orbits. The Bohr-Bury scheme suggests that the outermost shell of an atom has a maximum of 8 electrons.

Isotopes are atoms of the same element with the same atomic number but different mass numbers, due to variations in the number of neutrons in the nucleus.

Isotopes of specific elements have applications in various fields: Uranium isotopes are used as nuclear fuel, cobalt isotopes are used in cancer treatment, and iodine isotopes are used to treat goitre.

Isobars are atoms having the same mass number but different atomic numbers due to differences in both protons and neutrons.

The cell theory states that all living organisms are made up of cells, and all cells arise from pre-existing cells. Cells have an outer covering called the plasma membrane, separating the cell's contents from its environment.

The Golgi apparatus modifies and packages substances produced by the cell in vesicles, and it contributes to the formation of lysosomes, which act as waste disposal systems.

Mitochondria are known as the powerhouses of the cell. They produce energy (ATP) through cellular respiration and have their own DNA and ribosomes.

A tissue is a group of similar cells that work together to perform a specific function. Plants and animals have different types of tissues.

Meristematic tissues are responsible for plant growth. Their cells divide rapidly and differentiate into various types of permanent tissues, each specialized for a specific function, such as xylem and phloem.

Epithelial tissues form covering and protective layers in the animal body, while connective tissues support and bind different parts of the body. Blood is a type of connective tissue.

Stomata, tiny pores on leaves, are responsible for gas exchange and transpiration (water loss). Plastids, particularly chloroplasts, contain chlorophyll, giving plants their green color.

Xylem transports water and minerals upwards from roots to stems and leaves, while phloem transports food and nutrients both upwards and downwards throughout the plant.

Parthenogenesis is a form of reproduction where an embryo develops from a female gamete (egg) without fertilization by a male gamete.

Velocity is a vector quantity that includes both magnitude (speed) and direction. It can be positive or negative depending on the direction of motion. Speed, a scalar quantity, only considers magnitude and is always positive.

Gravitational force is always attractive, while electromagnetic force can be both attractive and repulsive depending on the charges involved.

Resonance occurs when an object is forced to vibrate at its natural frequency by an external force, potentially leading to increased amplitude and even breakage, as seen with a highly trained singer causing glass to shatter.

The Tyndall effect occurs when light is scattered by particles in a colloid or very fine suspension. It can be observed in a dense forest or a room with a light beam.

The line joining a planet and the Sun sweeps equal areas in equal intervals of time, known as Kepler's Second Law of Planetary Motion. The mean distance of a planet from the Sun is proportional to the square of its orbital period, as per Kepler's Third Law.

Micronutrients for plants are those needed in small amounts for optimal growth, including iron, copper, sulphur, and others.

Maharishi Kanad believed that matter could be endlessly divided into smaller particles, while Vatsyayana proposed the concept of the universe as a whole, without atomic existence. Kanad's ideas align with the modern understanding of atoms.

Citrus canker, rust of wheat, and yellow vein mosaic are plant diseases transmitted by air. Other means of transmission include insects and water.

A wave is a disturbance that travels through a medium, transferring energy by setting particles in motion. Sound waves are longitudinal waves, meaning particles vibrate parallel to the direction of wave propagation. They require a medium to travel, unlike electromagnetic waves like light.

Curving ceilings in auditoriums are used to reflect sound towards the audience, ensuring uniform sound distribution throughout the space.

The force of gravitation on a body, called its weight, is the force exerted by Earth's gravity on the body's mass. A person in an elevator accelerating downwards feels lighter because the apparent weight is reduced due to the opposing acceleration.

When a ball rolls down a slope at a steady speed, the forces acting on it are balanced. This means the forces of friction and the force pulling the ball down the slope are equal.

If the forces acting on an object are balanced, the object is in equilibrium. It will either be at rest or moving with a constant velocity.

The human brain coordinates various bodily functions such as maintaining blood pressure, regulating heartbeat, and balancing the body.

When pushing against a rigid wall, the work done is zero because there is no displacement, even though the force is applied. The internal energy used by the man is not zero, as he is expending effort.

Sound travels fastest in solids, followed by liquids, and slowest in gases. The speed of sound in air increases with temperature.

Isotopes have the same atomic number but different mass numbers. Isobars have the same mass number but different atomic numbers. Isotones have the same number of neutrons.

Prokaryotic cells lack a well-defined nucleus and membrane-bound organelles, while eukaryotic cells have a well-defined nucleus and membrane-bound organelles.

Mitochondria are the powerhouses of the cell, generating energy through cellular respiration. They have their own DNA and ribosomes.

A body falling freely under gravity in a vacuum starts with zero kinetic energy and gains kinetic energy while losing potential energy. The sum of potential and kinetic energy remains constant.

Kinetic energy is the energy of motion, indicating the work an object can do due to its movement. It is a scalar quantity (only magnitude, no direction). Doubling the velocity of an object increases its kinetic energy by a factor of four.

Steel has the highest speed of sound at 25 degrees Celsius, followed by water, and then air.

Sound waves cannot travel through a vacuum because they require a medium to propagate. Particles in a medium oscillate parallel to the direction of wave travel, and the speed of sound in a given medium is dependent on temperature and pressure, not frequency.

Bacteria are involved in curdling of milk, yeast is used for bread leavening, and fungi are involved in the production of citric acid.

Malaria is caused by a protozoan parasite, while measles and diphtheria are caused by viruses.

Blood, cartilage, and skin are tissues present in the human body. Blood is a fluid connective tissue, while cartilage and skin are specialized connective tissues and epithelial tissues, respectively.

Blood performs various essential functions in the body, including supplying carbon dioxide to living cells, transporting hormones to body parts, supplying water to body parts, and carrying oxygen.

Stomata are openings on leaves that allow for transpiration and gas exchange. Carotenoids are pigments that protect chlorophyll from photodamage, while root hairs absorb water and nutrients.

Light travels faster than sound. This is why you see lightning before you hear thunder.

Intercropping involves growing two or more crops simultaneously in a definite row pattern on the same field.

Apiculture is the science and practice of beekeeping, encompassing the care, management, and utilization of honeybees.

Cancer can be triggered by various factors, including non-ionizing radiation, viruses, and tobacco use. These factors can damage DNA and lead to uncontrolled cell growth.

HH-260 and B-77 are breeds of cows.

The quality of honey largely depends on the floral sources available to the bees. Apis dorsata is commonly known as the giant honey bee.

Planets like Venus and Mars have atmospheres composed of a high percentage of carbon dioxide, while Earth has a balanced composition of air.

Earth's atmosphere is primarily heated by solar radiation from the sun.

Lichens, which are symbiotic associations of fungi and algae, act as bio-indicators to assess pollution levels. They are sensitive to environmental changes and can indicate the health of the ecosystem.

The upward force acting on an object immersed in a liquid is called buoyant force. Buoyant force is influenced by gravity, as it is related to the weight of the fluid displaced by the object.

A sharp iron nail will require the least force to penetrate a piece of wood due to its concentrated force on a smaller surface area, compared to a blunt rod, thin sheet of steel, or a hammer.

All objects experience buoyant force when they are submerged in a fluid. Objects with a density greater than the density of the liquid will sink, while objects with lower density will float.

The law of gravitation describes the attractive force between any two bodies with mass. It is a universal force that governs the motion of planets, stars, and galaxies.

Weight is a force caused by gravity acting on an object's mass. It is a vector quantity, directed towards the center of Earth.

When a body is thrown upwards, kinetic energy is converted to potential energy as it rises. When a body falls, potential energy changes to kinetic energy. Unequal masses with the same momentum have different kinetic energies; the lighter mass has higher kinetic energy.

The velocity of sound in air decreases with increasing humidity because moist air is denser than dry air. Sound velocity in air is independent of pressure but increases with temperature. It remains the same for different frequencies.

Nitrogen cycling involves a series of processes that transform nitrogen in the atmosphere into forms that are usable by organisms. These include nitrogen fixation, nitrification, ammonification, and denitrification.

Liquified Petroleum Gas (LPG) is primarily composed of propane and butane.

Disinfectants are applied to living tissues to kill or prevent the growth of microorganisms, while tincture of iodine is a 2 percent Solution of iodine in an alcohol-water mixture, commonly used as an antiseptic.

The human microbiome refers to the diverse communities of microorganisms, mainly bacteria, that inhabit the human body. These include bacteria, fungi, archaea, protists, and viruses.

Forests play a crucial role in air purification by removing harmful pollutants from the atmosphere. They also prevent soil erosion by holding the soil together through their roots and helping maintain the temperature of the surrounding area through transpiration.

The blue color of the sky is caused by the scattering of sunlight by particles like dust and water droplets in the atmosphere. The reddish appearance of the sun during sunset and sunrise is due to the longer wavelengths of red light being scattered less by the atmosphere and reaching our eyes.

Cell wall structure is not a criterion for classifying animals. While cell walls are present in plants and fungi, animal cells lack them.