EST FGEI Past Papers MCQS

The correct answer is 4 because chemical bonds are broadly classified into four major types based on how atoms interact with and manipulate their valence electrons to achieve stability.

• Ionic Bonding (Electron Transfer): Occurs when an electropositive atom completely transfers one or more electrons to an electronegative atom, forming oppositely charged ions.


• Covalent Bonding (Electron Sharing): Formed when two atoms share pairs of valence electrons equally or unequally to satisfy their octets.


• Coordinate / Dative Bonding (Donated Sharing): A special type of covalent bond where the shared pair of electrons is provided entirely by a single donor atom.


• Metallic Bonding (Electron Delocalization): Formed among metal atoms where valence electrons are released into a shared, mobile 'sea' of delocalized electrons.


• Incorrect Options:
  
  
  
  • 1, 2, and 3 are incorrect because naming fewer than four types fails to capture the full spectrum of core chemical bonds found in foundational chemistry classification systems.
  
  

The correct answer is Iron because it is required by living organisms in minute quantities, yet it remains absolutely vital for physiological functions.

• Trace Element Role: Iron acts as a crucial cofactor in essential biological structures like hemoglobin, which is necessary for oxygen transport through the blood.


• Major (Macro) Elements: Elements like oxygen and carbon make up the vast bulk of organic tissue and matter, categorizing them as macro-elements rather than trace elements.


• Incorrect Options:
  
  
  
  • Oxygen is a major element that serves as a primary building block of water and organic cellular compounds.
  
  
  • Carbon forms the essential backbone of all organic molecules and life forms on Earth.
  
  
  • None of these is incorrect because Iron perfectly fits the definition of an essential trace element.
  
  

The correct answer is Henry Cavendish because he conducted the landmark experiment that first measured the weak force of gravitational attraction between masses in a laboratory setting.

• Cavendish Experiment: In 1798, Henry Cavendish used a highly sensitive torsion balance apparatus to calculate the density of the Earth, which directly yielded the first accurate value for the gravitational constant (G).
  
  


• Theoretical vs. Experimental: While other physicists formulated theories regarding gravity and space-time, they did not experimentally measure the absolute value of this universal constant.
  
  


• Incorrect Options:
  
  
  
  • Einstein revolutionized physics with his General Theory of Relativity, which describes gravity as space-time curvature rather than a mechanical force.
  
  
  • Newton discovered the Law of Universal Gravitation and introduced the concept of the gravitational constant but lacked the precise instrumentation to measure its numerical value.
  
  
  • Stephen Hawking made monumental contributions to theoretical physics regarding black holes and cosmology long after the gravitational constant was already established.
  
  

The correct answer is 2 because of the specific energetic requirements during the initial preparation stage of cellular respiration.

• Energy Investment Phase: During the first half of glycolysis, the cell must actually expend energy to break down glucose. Exactly 2 ATP molecules are consumed—one by the enzyme hexokinase and another by phosphofructokinase—to destabilize the glucose molecule.


• Energy Production Contrast: While 4 ATP molecules are subsequently produced later in the energy-payoff phase, subtracting the 2 invested ATP molecules results in a net gain of 2 ATP for the cell.


• Incorrect Options:
  
  
  
  • 4 is incorrect because it represents the total number of gross ATP molecules produced, not the amount used or consumed.
  
  
  • 3 is incorrect because there is no biochemical step in the standard glycolysis pathway that consumes an odd number of ATP molecules.
  
  
  • 6 is incorrect because it vastly overstates the energy investment required to initiate the metabolic breakdown of a single glucose molecule.
  
  

The correct answer is Reptiles because herpetology is the specific branch of zoology dedicated to studying both reptiles and amphibians.

• Scientific Scope: Herpetology investigates the behaviors, anatomy, genetics, and ecologies of ectothermic (cold-blooded) tetrapods, which encompasses creatures like snakes, lizards, turtles, frogs, and salamanders.


• Etymology: The term comes from the Greek word 'herpein', which means 'to creep' or 'to crawl', describing the movement style typical of most reptiles and amphibians.


• Incorrect Options:
  
  
  
  • Fish are studied under a separate branch of zoology known as ichthyology.
  
  
  • Birds are the focus of a specialized zoological field called ornithology.
  
  
  • Mammals are researched within the scientific discipline referred to as mammalogy.
  
  

The correct answer is Tundra because it represents the specific biome located at high latitudes where extreme cold prevents tree growth.

• Environmental Constraints: The tundra biome features short growing seasons and a layer of permanently frozen subsoil called permafrost, which completely prevents deep root systems from forming.


• Vegetation Types: Instead of trees, the vegetation in tundra ecosystems consists primarily of dwarf shrubs, sedges, grasses, mosses, and lichens adapted to survive severe cold and wind.


• Incorrect Options:
  
  
  
  • Desert is incorrect because it is defined primarily by extremely low rainfall rather than high latitude, and can be either hot or cold.
  
  
  • Forest is incorrect because it describes a biome explicitly dominated by dense tree covers, the exact opposite of a treeless region.
  
  
  • Grassland is incorrect because while it is mostly treeless, it typically thrives in temperate and tropical mid-latitude zones rather than extreme high-latitude polar regions.
  
  

The correct answer is Infection because an elevated white blood cell count is a benchmark clinical response to invading pathogens.

• Immune Proliferation: When the body detects a bacterial, viral, or fungal invasion, chemical signals prompt the bone marrow to rapidly produce and mobilize leucocytes to attack and neutralize the pathogen.


• Leukocytosis Sign: This rise in the white blood cell population, medically termed leukocytosis, serves as a vital diagnostic indicator that an active inflammatory or infectious process is occurring in the body.


• Incorrect Options:
  
  
  
  • Anaemia is incorrect because it relates to a deficiency in red blood cells or hemoglobin, rather than an overproduction of white blood cells.
  
  
  • Increased defense is structurally a description of the purpose behind the cell rise rather than the clinical pathology or root condition (the infection) that the test actually indicates.
  
  
  • Non formation RBC is incorrect because it describes erythroid marrow suppression, which is an independent hematological problem unrelated to standard leucocyte proliferation.
  
  

The correct answer is Pressure because of the foundational physical definition of force acting across a dimensional area.

• Mathematical Derivation: Pressure is calculated using the formula P = F / A (Force divided by Area). Substituting the standard SI units gives Newtons (N) divided by square meters (m²), which simplifies notationally to Nm⁻².


• The Pascal: This combined metric unit (Nm⁻²) is so fundamental to physics and thermodynamics that it is given its own dedicated name, the Pascal (Pa).


• Incorrect Options:
  
  
  
  • Energy is incorrect because its standard SI unit is the Joule (J), which translates dimensionally to Newton-meters (Nm).
  
  
  • Work is incorrect because like energy, it represents force applied across a distance and is measured strictly in Joules (Nm).
  
  
  • Density is incorrect because mass density measures mass per unit volume, which is expressed in kilograms per cubic meter (kgm⁻³).
  
  

The correct answer is 3900 km as it is the closest estimate to the core's actual total thickness, though the exact combined radius of the inner and outer core is roughly 3,485 km.

• Core Dimensions: The Earth's core is divided into two parts: a liquid outer core that is about 2,260 km thick and a solid inner core with a radius of about 1,220 km. Combined, they give the total core a structural thickness of nearly 3,480 km.


• The 2,900 km Confusion: The value of 2,900 km represents the depth below the Earth's surface where the mantle ends and the core begins (the Gutenberg Discontinuity), as well as the thickness of the mantle itself, rather than the core's thickness.


• Incorrect Options:
  
  
  
  • 500 km is far too thin and does not align with any major planetary layer measurements of the Earth.
  
  
  • 2900 km is incorrect because it specifies the starting depth boundary of the core below the crust, not the measurement of the core itself.
  
  
  • 1900 km is an underestimation that fails to account for the massive scale of the combined inner and outer core structures.
  
  

The correct answer is Anterior pituitary because it is the specific endocrine structure responsible for producing and secreting growth hormone.

• Pathophysiology: Acromegaly develops in adults when specialized cells inside the front lobe (the anterior pituitary) develop a benign tumor, leading to chronic overproduction of growth hormone (GH).


• Anatomical Distinction: The pituitary gland is split into distinct lobes; only the anterior lobe synthesizes growth hormone, whereas the posterior lobe does not produce it.


• Incorrect Options:
  
  
  
  • Thyroid gland is incorrect because it functions to regulate cellular metabolism via thyroxine and triiodothyronine secretions.
  
  
  • Adrenal gland is incorrect because it produces hormones like cortisol, adrenaline, and aldosterone to regulate stress responses and fluid balances.
  
  
  • Thymus gland is incorrect because it operates primarily within the immune system to facilitate the training and maturation of T-lymphocytes.