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The correct answer is Tortoise

Explanation:

• A tortoise is not a true amphibian animal. Tortoises are reptiles, whereas frogs, toads, and salamanders are true amphibians.
• Tortoises have dry, scaly skin and lay their eggs on land. They do not undergo metamorphosis and do not have a stage of their life cycle in water.
• They are mostly terrestrial and adapted for a dry environment.
• Tortoises are not true amphibians because they do not have the life cycle and physiological characteristics typical of amphibians.

Amphibians

• Amphibians can live in aquatic as well as terrestrial habitats.
• Most of the amphibians have two pairs of limbs.
• The amphibian's skin remains moist(without scales).
• The heart of an amphibian is three-chambered.

Examples of amphibian are:

• Bufo (Toad).
• Rana (Frog).
• Hyla (Tree frog).
• Salamandra (Salamander).
• Ichthyophis (Limbless amphibia).

The correct answer is High pressure, low temperature

Explanation:

• High pressure: Applying high pressure to a gas decreases the volume available for gas molecules to move around.

This increased density of gas particles encourages intermolecular interactions, making it easier for the gas to transition into a liquid state.

• Low temperature: Lowering the temperature reduces the kinetic energy of the gas molecules.

When molecules move slower, they are more likely to stick together when they collide, promoting the formation of a liquid.

 Key Points

• High pressure: Increasing the external pressure on a gas forces the molecules closer together, increasing the chance of intermolecular attractions and phase change to a liquid.
• Low temperature: Cooling a gas decreases the kinetic energy of its molecules, making it easier for them to coalesce into a liquid. Lower temperatures mean molecules are less energetic and more likely to attract each other.

Therefore, the most favourable condition for converting a gas into a liquid is a combination of high pressure and low temperature. High pressure compresses the gas, and low temperature reduces the kinetic energy, both factors contributing to the condensation of the gas into a liquid.

Explanation:

Kepler's Third Law (Law of Harmonies) Formula:

The formula for Kepler's Third Law is:

$\frac{T^2}{a^3} = \text{constant}$

Where:

• T represents the orbital period of the planet (the time it takes for the planet to complete one full orbit around the sun).
• a represents the semi-major axis of the planet's orbit (average distance from the sun).

In a simplified form, for any two planets orbiting the same star (including the sun), Kepler's Third Law can be written as:

$\frac{T_1^2}{a_1^3} = \frac{T_2^2}{a_2^3}$

Where:

• T1 and T2 are the orbital periods of two different planets.
• a1 and a2 are the semi-major axes of their orbits.

 Key Points

• Kepler's First Law (Law of Ellipses): The orbit of a planet around the sun is an ellipse with the sun at one of the two foci.
• Kepler's Second Law (Law of Equal Areas): A line segment joining a planet and the sun sweeps out equal areas during equal intervals of time, meaning that planets move faster when they are closer to the sun and slower when they are farther from the sun.
• Kepler's Third Law (Law of Harmonies): The square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit, which can be expressed as $T^2 \propto r^3$ , where T is the orbital period and r is the semi-major axis.

Therefore, the orbits of planets around the sun are described by Kepler's laws.

The correct answer is Non-metals

Explanation:

• Non-metals: These are elements that generally have poor electrical and thermal conductivity.

Unlike metals, non-metals do not have free electrons that facilitate the flow of electric current or heat.

Examples of non-metals include sulfur, carbon in the form of diamond and gases like oxygen and nitrogen.

Exception Graphite which is good conductor of electricity

 Key Points

• Metals: Known for their excellent conductivity of heat and electricity, metals have free electrons that can move easily through the metal's lattice structure. Examples include copper, aluminum, and gold.
• Gases: While some gases can be poor conductors, they are generally not classified for their conductivity properties in the same manner as solid elements. Many gases are non-metals, such as oxygen and nitrogen.
• Non-metals: These elements are typically insulators. They have tightly bound electrons that do not move freely, making them poor conductors. Common non-metals like phosphorus and sulfur exemplify these insulating properties.

Therefore, non-metals are the type of elements that are generally poor conductors of heat and electricity.

The correct answer is Electronic configuration

Explanation:

Electronic configuration:

• ​This refers to the arrangement of electrons in an atom's orbitals.
• It follows a specific order based on increasing energy levels and is governed by principles such as the Aufbau principle, Hund's rule, and the Pauli exclusion principle.

 Key Points

• Electronic configuration: Specifies how electrons are distributed in the atomic orbitals of an atom. For example, the electronic configuration of carbon (atomic number 6) is 1s² 2s² 2p².
• Aufbau Principle: Electrons fill atomic orbitals beginning from the lowest energy level to the highest, ensuring that lower-energy orbitals are filled before higher ones.
• Hund's Rule: Electrons will fill degenerate orbitals (orbitals at the same energy level) singly before pairing up to ensure maximum spin multiplicity.
• Pauli Exclusion Principle: No two electrons in an atom can have the same set of four quantum numbers, meaning each electron in an atom has a unique state.

The electronic configuration of an atom determines its chemical properties and how it will interact with other atoms.

The correct answer is Ultra short radio waves

Explanation:

• J.C. Bose: Jagadish Chandra Bose was an Indian physicist, biologist, botanist, and an early writer of science fiction. He is considered one of the pioneers in the field of radio and microwave optics.
• Ultra short radio waves: J.C. Bose conducted pioneering research on the propagation of electromagnetic waves, including ultra short radio waves.

His work demonstrated the behavior of these waves, which laid the groundwork for the development of wireless communication technology.

 Key Points

• J.C. Bose: Known for his groundbreaking experiments in the field of microwave optics and plant physiology, he was one of the first to use semiconductor junctions to detect radio signals.
• Ultra short radio waves: These are electromagnetic waves with very short wavelengths, which Bose extensively studied. His research contributed significantly to the development of radio technology.

J.C. Bose's discoveries in the realm of ultra short radio waves had a profound impact on modern communication systems, and his work is still recognized and celebrated in the field of physics and beyond.

The correct answer is Food vacuole

Explanation:

• In an amoeba, food is digested in the food vacuole.
• When an amoeba engulfs food particles using its pseudopodia, the food particles are enclosed within a food vacuole, where digestive enzymes break down the food into nutrients that the amoeba can absorb.

Key Points

• Amoeba is a single-celled microscopic organism found in pond water.
• In its cytoplasm, the amoeba has a cell membrane, a rounded, dense nucleus, and numerous small bubble-like vacuoles.
• Amoeba constantly changes their shape and position.
• It pushes out one, or more finger-like projections, called pseudopodia (false feet) for movement and capture of food.
• Amoeba feeds on some microscopic organisms.
• When it senses food, it pushes out pseudopodia around the food particle and engulfs it.
• Amoeba takes in food using temporary finger-like extensions of the cell surface which fuse over the food particle forming a food vacuole.
• Complex substances are broken down inside the food vacuole into simpler ones, which then diffuse into the cytoplasm.
• The remaining undigested material is moved to the surface of the cell and thrown out.

The correct answer is Cytoplasm

Explanation:

Glycolysis:

• The term glycolysis has originated from the Greek words, glycos for sugar, and lysis for splitting.
• The scheme of glycolysis was given by Gustav Embden, Otto Meyerhof, and J. Parnas, and is often referred to as the EMP pathway.
• In anaerobic organisms, it is the only process in respiration.
• Glycolysis occurs in the cytoplasm of the cell and is present in all living organisms.
• In this process, glucose undergoes partial oxidation to form two molecules of pyruvic acid.
• In plants, this glucose is derived from sucrose, which is the end product of photosynthesis, or from storage carbohydrates.
• Sucrose is converted into glucose and fructose by the enzyme, invertase, and these two monosaccharides readily enter the glycolytic pathway.
• Glucose and fructose are phosphorylated to give rise to glucose-6- phosphate by the activity of the enzyme hexokinase.
• This phosphorylated form of glucose then isomerizes to produce fructose-6- phosphate.
• Subsequent steps of metabolism of glucose and fructose are the same.
• In glycolysis, a chain of ten reactions, under the control of different enzymes, takes place to produce pyruvate from glucose.

The correct answer is Earthworm

Explanation:

• The organism that breathes through its skin is the earthworm. Earthworms have a moist, permeable skin through which gas exchange (oxygen and carbon dioxide) occurs, allowing them to "breathe" directly through their skin.
• They lack specialized respiratory organs like lungs or gills.For skin respiration to be effective, the skin must remain moist.
• Mucus and coelomic fluid (body fluid) keep their skin damp, which helps dissolve oxygen from the environment.
• Oxygen diffuses through the moist skin directly into the blood vessels beneath the skin, and carbon dioxide diffuses out.

Additional Information

Snake:

• Snakes breathe through their lungs. They have a pair of lungs, but some species have a reduced or even non-functional left lung. Air is inhaled through their nostrils or mouth, travels down the trachea, and reaches the lungs where gas exchange occurs.
• Some aquatic snakes can absorb a small amount of oxygen through their skin, but this is not their primary method of respiration.

Monkey:

• Monkeys, like other mammals, have a complex respiratory system that includes lungs, trachea, and a diaphragm muscle.
• Air is inhaled through the nose or mouth, travels through the trachea, into the bronchi, and finally reaches the alveoli in the lungs where gas exchange occurs.
• Their respiratory system is well-adapted for breathing air in terrestrial environments.

Humans:

• Humans also rely on lungs for respiration. The process is similar to that in monkeys, involving the nasal passages, trachea, bronchi, and alveoli for gas exchange.
• The diaphragm and intercostal muscles help in expanding and contracting the lungs to inhale and exhale air efficiently.

The correct answer is All of the above

Concept:

Ecosystem:

• It is a self-contaminated unit of living things (plants, animals, and decomposes), and their non-living environment (soil, air, and water).
• Examples of ecosystems are grassland, forest, desert, mountain, ponds, and seas.

All ecosystems are made up of two main components:

• Abiotic components
• Biotic components

Abiotic components

• The abiotic components of an ecosystem include the physical environment like soil, water, and air along with the inorganic substances like carbon dioxide, nitrogen, oxygen, water, etc.
• The physical factors or climatic factors like light, temperature, pressure, and humidity are also considered abiotic components of the ecosystem.

Biotic components

• The biotic components of an ecosystem are a community of organisms, which is made up of many different interdependent populations.

The biotic community of an ecosystem includes three types of organisms:-

• Producer organisms
• Consumer organisms
• Decomposer organisms