General Science Topics
Undergraduate level — General Science
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quiz Questions
Q181
Which unique metabolic feature distinguishes the prokaryotic archaebacteria found inside extreme deep-sea hydrothermal vents from typical eukaryotic organisms?
Absolute reliance on photoautotrophic sugar tracking
Chemosynthesis utilizing inorganic chemical oxidation paths
An external mitochondrial cellular aerobic breathing loop
The synthesis of complex cross-linked cellulose frameworks
Explanation
Deep-sea vent archaebacteria rely on Chemosynthesis. Because there is no sunlight, they manufacture organic molecules by oxidizing inorganic chemicals like hydrogen sulphide (H2S) instead of using solar energy.
Q182
The display technology infrastructure known as 'Quantum Dot LED' (QLED) improves over standard LCD configurations using which nano-technological element?
Organic macro-molecular fluorescent dye patterns
Microscopic semiconductor nanocrystals that emit highly precise light wavelengths
High-velocity gaseous plasma ionization chambers
Asymmetric cathode ray tracking deflection matrices
Explanation
QLED televisions utilize microscopic semiconductor nanocrystals called Quantum Dots. When illuminated by a blue LED backlight, these quantum dots emit highly precise and vibrant primary colors (red and green), enhancing color accuracy.
Q183
Which of the following descriptions accurately characterizes the ecological indicator role of benthic macroinvertebrates inside a freshwater river grid?
They serve as primary vectors for airborne viral pathogens
Their species composition and diversity act as a sensitive proxy for water quality and pollution levels
They accelerate the fixation of atmospheric nitrogen gases inside river silt
They multiply exponentially when heavy radioactive isotopes contaminate the ecosystem
Explanation
Benthic macroinvertebrates (like Mayfly and Stonefly nymphs) live on the river bottom and are highly sensitive to water pollution and dissolved oxygen drops. Their composition shifts indicate long-term water quality variations.
Q184
A satellite moves with uniform orbital speed V along a circular path of radius R around the Earth. What is the total work done on the satellite by the Earth's gravitational pull during one full orbit?
Zero
½ m V²
2 π R × F
m g R
Explanation
Work done is defined as W = F·d·cos(θ). In a circular orbit, the centripetal gravitational force vector is always perpendicular (θ = 90°) to the instantaneous displacement vector (tangential velocity). Since cos(90°) = 0, the total work done is zero.
Q185
Which chemical statement coordinates the volume relationships of gaseous reactants and products in a balanced chemical reaction at constant temperature and pressure?
Dalton's Atomic Theory Law
Gay-Lussac's Law of Combining Volumes
Henry's Mass Dissolution Rule
Hess's Law of Constant Heat Summation
Explanation
Gay-Lussac's Law of Combining Volumes states that when gases react together, they do so in volumes which bear a simple whole-number ratio to one another and to the volumes of gaseous products, if measured at the same temperature and pressure.
Q186
Which specialized microscopic structure inside the human lung framework acts as the definitive site for rapid gas exchange with surrounding capillary beds?
Trachea Rings
Alveoli
Bronchi Passageways
Pleural Cavity Wall
Explanation
The Alveoli are tiny, bubble-like air sacs at the terminal ends of the bronchioles. Their ultra-thin squamous epithelial walls allow simple diffusion of oxygen into the blood and carbon dioxide out of it.
Q187
An object of mass 2 kg is dropped from a tower of height 45 meters. Neglecting air resistance, what will be its kinetic energy just before hitting the ground? (Take g = 10 m/s²)
450 J
900 J
1800 J
90 J
Explanation
According to the law of conservation of mechanical energy, the initial potential energy at the top converts entirely into kinetic energy at the bottom. Potential Energy = mgh = 2 kg × 10 m/s² × 45 m = 900 Joules. Therefore, the final kinetic energy is 900 Joules.
Q188
Which chemical law states that the total mass of the reactants is equal to the total mass of the products in a closed system chemical reaction?
Law of Definite Proportions
Law of Conservation of Mass
Law of Multiple Proportions
Avogadro's Law
Explanation
The Law of Conservation of Mass, formulated by Antoine Lavoisier, establishes that matter can neither be created nor destroyed in a chemical reaction, meaning total mass remains constant.
Q189
Which structural type of division allows a diploid somatic cell to yield two genetically identical diploid daughter cells during growth?
Meiosis
Mitosis
Amitosis
Binary Fission
Explanation
Mitosis is the process of equational cell division where a single somatic cell divides to produce two genetically identical daughter cells, maintaining the original chromosome number.
Q190
What is the primary operational objective of the 'LiFi' (Light Fidelity) wireless communication technology?
To stream acoustic tracking currents inside ocean trenches
To transmit high-speed data utilizing the visible light spectrum
To accelerate thermodynamic cryogenic core cooling matrices
To calibrate long-range radar beams over industrial valleys
Explanation
LiFi is a bidirectional, high-speed wireless communication technology that uses light-emitting diodes (LEDs) to transmit data via visible light spectrum waves instead of radio waves used in WiFi.