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Question 1 · Botany · Plant Growth and Development

Which one of the following phases of growth is characterized by the highest rate of increase in dry mass and cell number?

1. Lag phase
2. Exponential (log) phase
3. Stationary phase
4. Senescent phase

Question 2 · Botany · Mineral Nutrition

Which one of the following statements correctly distinguishes essential elements from beneficial elements?

1. Beneficial elements are required in greater quantities than essential elements.
2. Essential elements are indispensable for completion of the plant life cycle.
3. Beneficial elements are constituents of all enzymes.
4. Essential elements are absorbed only from the atmosphere.

Question 3 · Botany · Mineral Nutrition

A plant is grown in a nutrient solution containing all essential elements except iron. Which physiological process is expected to be affected most directly?

1. Formation of calcium pectate
2. Electron transport during photosynthesis and respiration
3. Photolysis of water
4. Hydrolysis of urea

Question 4 · Botany · Photosynthesis in Higher Plants

Which one of the following pigments has the highest abundance among the chlorophyll pigments present in higher plants?

1. Chlorophyll b
2. Chlorophyll a
3. P680
4. P700

Question 5 · Botany · Morphology of Flowering Plants

Which one of the following is the primary function of the root system in flowering plants?

1. Photosynthesis
2. Absorption of water and minerals from the soil
3. Production of flowers
4. Translocation of food

Question 6 · Botany · Morphology of Flowering Plants

A seedling loses its primary root shortly after germination, following which several roots arise from the basal region of the stem. Which type of root system will eventually develop?

1. Tap root system
2. Fibrous root system
3. Pneumatophore
4. Prop root system

Question 7 · Botany · Plant Growth and Development

During the exponential phase of plant growth, the increase in size is directly proportional to:

1. The age of the plant only
2. The amount of living tissue already present
3. The concentration of chlorophyll only
4. The number of stomata per unit area

Question 8 · Botany · Cell – The Unit of Life

Who proposed the Cell Theory?

1. Robert Hooke and Robert Brown
2. Schleiden and Schwann
3. Virchow and Brown
4. Leeuwenhoek and Hooke

Question 9 · Botany · Cell – The Unit of Life

Which statement is NOT a part of the original Cell Theory proposed by Schleiden and Schwann?

1. All living organisms are composed of cells
2. Cells are the basic unit of life
3. All cells arise from pre-existing cells
4. Organisms are composed of one or more cells

Question 10 · Botany · Respiration in Plants

During glycolysis, how many molecules of NADH are formed from one molecule of glucose?

1. 1
2. 2
3. 4
4. 6

Question 11 · Botany · Photosynthesis in Higher Plants

Which one of the following accessory pigments is oxygen-containing and appears yellow in colour?

1. Carotene
2. Xanthophyll
3. Chlorophyll a
4. Chlorophyll b

Question 12 · Botany · Cell Cycle and Cell Division

According to NCERT, the phase of the cell cycle during which DNA replication occurs is:

1. G₁ Phase
2. S Phase
3. G₂ Phase
4. M Phase

Question 13 · Botany · Cell Cycle and Cell Division

Which of the following correctly represents the sequence of stages in interphase?

1. G₂ → G₁ → S
2. S → G₁ → G₂
3. G₁ → S → G₂
4. G₁ → G₂ → S

Question 14 · Botany · Biomolecules

Which of the following carbohydrates is the most abundant organic compound present on Earth?

1. Starch
2. Cellulose
3. Glycogen
4. Chitin

Question 15 · Botany · Biomolecules

Which statement correctly distinguishes starch from cellulose?

1. Both are composed of β-glucose linked by β(1→4) glycosidic bonds.
2. Starch contains α-glucose whereas cellulose contains β-glucose.
3. Both are branched polysaccharides.
4. Cellulose is the storage polysaccharide of plants.

Question 16 · Botany · Biological Classification

According to Whittaker's five kingdom classification, which kingdom includes all prokaryotic organisms?

1. Protista
2. Fungi
3. Monera
4. Plantae

Question 17 · Botany · Biological Classification

Which one of the following was NOT used by R.H. Whittaker as a criterion for the five kingdom classification?

1. Cell structure
2. Mode of nutrition
3. Phylogenetic relationship
4. Blood vascular system

Question 18 · Botany · Anatomy of Flowering Plants

Match the following. List I P. Apical meristem Q. Intercalary meristem R. Lateral meristem S. Permanent tissue List II 1. Secondary growth 2. Differentiated tissue 3. Increase in plant length 4. Regrowth of grasses Choose the correct option.

1. P-3, Q-4, R-1, S-2
2. P-4, Q-3, R-2, S-1
3. P-3, Q-1, R-4, S-2
4. P-2, Q-4, R-1, S-3

Question 19 · Botany · Anatomy of Flowering Plants

Which one of the following simple permanent tissues is composed of living cells with unevenly thickened cell walls at the corners?

1. Parenchyma
2. Collenchyma
3. Sclerenchyma
4. Xylem fibres

Question 20 · Botany · Respiration in Plants

Glycolysis takes place in which of the following cellular locations?

1. Mitochondrial matrix
2. Cytoplasm (cytosol)
3. Inner mitochondrial membrane
4. Chloroplast stroma

Question 21 · Botany · The Living World

The term 'biodiversity' refers to:

1. Diversity only at the species level
2. The number of plants present in a region
3. The diversity among genes, species and ecosystems
4. Only the diversity of microorganisms

Question 22 · Botany · The Living World

Two forests contain the same number of plant species. However, Forest A has high genetic variation within each species, whereas Forest B has very little genetic variation. Which forest possesses greater biodiversity?

1. Forest A
2. Forest B
3. Both forests have equal biodiversity
4. Cannot be determined

Question 23 · Botany · Transport in Plants

Which of the following is an essential macronutrient required by plants?

1. Iron
2. Zinc
3. Nitrogen
4. Molybdenum

Question 24 · Botany · Transport in Plants

A plant grown in nutrient solution develops chlorosis mainly in older leaves, while younger leaves remain green. Which deficiency is most likely responsible?

1. Calcium
2. Nitrogen
3. Iron
4. Boron

Question 25 · Botany · Plant Kingdom

Which of the following characteristics is unique to bryophytes among the given plant groups?

1. Presence of vascular tissues
2. Dominant sporophytic generation
3. Water is essential for fertilization
4. Formation of naked seeds

Question 26 · Chemistry · Some Basic Concepts of Chemistry

The mass of 3.011 × 10^23 molecules of NH3 is:

1. 8.5 g
2. 17 g
3. 34 g
4. 4.25 g

Question 27 · Chemistry · Some Basic Concepts of Chemistry

How many hydrogen atoms are present in 0.2 mol of CH4?

1. 2.408 × 10^23
2. 4.816 × 10^23
3. 6.022 × 10^23
4. 9.633 × 10^23

Question 28 · Chemistry · Chemical Bonding and Molecular Structure

The formal charge on carbon in the cyanide ion (CN−) is:

1. -1
2. 0
3. +1
4. +2

Question 29 · Chemistry · States of Matter

A gas occupies 600 mL at 27°C. What will be its volume at 127°C if pressure remains constant?

1. 700 mL
2. 750 mL
3. 800 mL
4. 900 mL

Question 30 · Chemistry · Amines

How many of the following are correct IUPAC names? (i) Methanamine (ii) Ethanamine (iii) Benzenamine (iv) Methylamine

1. 1
2. 2
3. 3
4. 4

Question 31 · Chemistry · Polymers

Which one of the following is a condensation polymer?

1. PVC
2. PTFE
3. Dacron
4. Polypropene

Question 32 · Chemistry · Polymers

How many of the following are condensation polymers? (i) Nylon-6,6 (ii) Dacron (iii) Bakelite (iv) PVC

1. 1
2. 2
3. 3
4. 4

Question 33 · Chemistry · Structure of Atom

Which of the following observations could NOT be explained by Thomson's atomic model?

1. Atom is electrically neutral.
2. Electrons are present inside the atom.
3. Existence of a small, dense, positively charged nucleus.
4. Positive and negative charges are distributed throughout the atom.

Question 34 · Chemistry · Classification of Elements and Periodicity

Which one of the following electronic configurations corresponds to an element placed in Period 4 but NOT in the p-block?

1. [Ar]3d¹⁰4s²4p²
2. [Ar]3d⁵4s²
3. [Ar]3d¹⁰4s²4p⁵
4. [Ar]3d¹⁰4s²4p⁶

Question 35 · Chemistry · Chemical Bonding and Molecular Structure

The total number of lone pairs present in the Lewis structure of HCl is:

1. 2
2. 3
3. 4
4. 5

Question 36 · Chemistry · States of Matter

A fixed mass of gas occupies 8.0 L at 2 atm. If the pressure is reduced to 0.5 atm at constant temperature, the final volume will be:

1. 16 L
2. 24 L
3. 32 L
4. 4 L

Question 37 · Chemistry · Redox Reactions

Which one of the following reactions is not a redox reaction?

1. CaCO3 → CaO + CO2
2. 2KClO3 → 2KCl + 3O2
3. Zn + 2HCl → ZnCl2 + H2
4. 2NO + O2 → 2NO2

Question 38 · Chemistry · Thermodynamics

A gas enclosed in a perfectly insulated cylinder fitted with a frictionless movable piston is compressed rapidly by an external force. Which of the following is necessarily true immediately after compression?

1. q = 0 and w > 0
2. q > 0 and w = 0
3. q = 0 and w = 0
4. q < 0 and w < 0

Question 39 · Chemistry · The p-Block Elements (Group 13 & 14)

An element X belongs to Group 16 of the p-block. Which of the following correctly represents its valence shell electronic configuration?

1. ns²np²
2. ns²np³
3. ns²np⁴
4. ns²np⁵

Question 40 · Chemistry · Hydrocarbons

Which hydrocarbon gives a yellow luminous flame due to its high carbon content?

1. Methane
2. Ethane
3. Benzene
4. Propane

Question 41 · Chemistry · Equilibrium

For the reaction A + B ⇌ C, the equilibrium concentrations are [A] = 2 M, [B] = 3 M and [C] = 12 M. The value of Kc is:

1. 1
2. 2
3. 3
4. 4

Question 42 · Chemistry · Alcohols, Phenols and Ethers

Assertion (A): Alcohols undergo dehydration in the presence of concentrated H₂SO₄ to form alkenes. Reason (R): Concentrated H₂SO₄ acts as a dehydrating agent by removing a molecule of water from the alcohol.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Question 43 · Chemistry · Aldehydes, Ketones and Carboxylic Acids

Which of the following compounds undergoes the Cannizzaro reaction?

1. CH₃CHO
2. CH₃CH₂CHO
3. HCHO
4. CH₃COCH₃

Question 44 · Chemistry · Amines

Which reagent converts benzenediazonium chloride into chlorobenzene?

1. KI
2. CuCl/HCl
3. H₂O
4. HBF₄

Question 45 · Chemistry · Solutions

For a solute undergoing association in solution, the van't Hoff factor (i) is:

1. Greater than 1
2. Equal to 1
3. Less than 1
4. Equal to 2

Question 46 · Chemistry · Electrochemistry

According to the Nernst equation, at 298 K the value of (2.303RT/F) is approximately:

1. 0.0295 V
2. 0.0591 V
3. 0.1182 V
4. 0.2364 V

Question 47 · Chemistry · Chemical Kinetics

An elementary reaction involves one molecule of A and two molecules of B reacting simultaneously. Its molecularity is:

1. 1
2. 2
3. 3
4. 4

Question 48 · Chemistry · d- and f-Block Elements

The actinoid series involves the progressive filling of which orbitals?

1. 3d
2. 4f
3. 5f
4. 6d

Question 49 · Chemistry · Haloalkanes and Haloarenes

How many of the following reagents can convert alcohols into haloalkanes? (i) HCl (ii) SOCl₂ (iii) PBr₃ (iv) HI

1. 2
2. 3
3. 4
4. 1

Question 50 · Chemistry · Coordination Compounds

Assertion (A): Werner proposed that metal ions in coordination compounds possess two types of valencies. Reason (R): Primary valency is ionisable, whereas secondary valency is non-ionisable and directional.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Question 51 · Physics · Motion in One Dimension

A particle moves from x = 4 m to x = -8 m. The displacement of the particle is:

1. -12 m
2. 12 m
3. 4 m
4. -4 m

Question 52 · Physics · Units and Dimensions

The dimensional formula of surface tension is:

1. [MT⁻²]
2. [MLT⁻²]
3. [ML⁻¹T⁻²]
4. [ML²T⁻²]

Question 53 · Physics · Motion in Two Dimensions

Which of the following is a vector quantity?

1. Distance
2. Speed
3. Work
4. Displacement

Question 54 · Physics · Laws of Motion

A 5 kg block rests on a rough horizontal surface. The coefficient of static friction is 0.4. The minimum horizontal force required to start the motion of the block is (g = 10 m/s²):

1. 10 N
2. 15 N
3. 20 N
4. 25 N

Question 55 · Physics · Work Power and Energy

A force of 50 N acts on a body and displaces it by 4 m in the direction of the force. The work done is:

1. 50 J
2. 100 J
3. 200 J
4. 400 J

Question 56 · Physics · Rotational Motion

A wheel rotates through an angle of 20 rad in 4 s. Its average angular velocity is:

1. 2 rad/s
2. 4 rad/s
3. 5 rad/s
4. 8 rad/s

Question 57 · Physics · Centre of Mass and Momentum

Two particles of masses 2 kg and 3 kg are placed at x = 0 m and x = 10 m respectively. The position of the center of mass is:

1. 4 m
2. 5 m
3. 6 m
4. 7 m

Question 58 · Physics · Mechanical Properties of Fluids

The SI unit of coefficient of viscosity is:

1. N/m
2. Pa·s
3. N·m
4. kg/m²

Question 59 · Physics · Gravitation

A satellite is orbiting Earth at radius 2R from Earth's center. If its orbital speed is v, the escape speed from that orbit is:

1. v
2. √2 v
3. 2v
4. v/√2

Question 60 · Physics · Current Electricity

A current of 5 A flows through a resistor of 4 Ω. The potential difference across the resistor is:

1. 9 V
2. 20 V
3. 25 V
4. 40 V

Question 61 · Physics · Mechanical Properties of Solids

A wire of length L and cross-sectional area A is stretched by a force F. If both the length and diameter of the wire are doubled while the same force acts, the strain produced becomes:

1. One-fourth
2. Half
3. Same
4. Double

Question 62 · Physics · Waves

A wave travels with a frequency of 250 Hz and a wavelength of 1.2 m. The speed of the wave is:

1. 200 m/s
2. 250 m/s
3. 300 m/s
4. 550 m/s

Question 63 · Physics · Thermodynamics

An ideal gas undergoes an isothermal expansion from volume V to 4V at temperature T. If the work done is W, the heat absorbed by the gas is:

1. 0
2. W/2
3. W
4. 2W

Question 64 · Physics · Magnetism and Matter

The magnetic field lines inside a bar magnet are directed:

1. From North pole to South pole
2. From South pole to North pole
3. Randomly
4. They do not exist inside the magnet

Question 65 · Physics · Electrostatic Potential and Capacitance

The SI unit of capacitance is:

1. Volt
2. Coulomb
3. Farad
4. Joule

Question 66 · Physics · Alternating Current

The frequency of an AC source is 60 Hz. Its time period is:

1. 0.60 s
2. 0.06 s
3. 0.0167 s
4. 0.00167 s

Question 67 · Physics · Electric Charges and Fields

Two identical point charges are placed 20 cm apart in vacuum. If the electrostatic force between them is doubled without changing the medium, the new separation between the charges should be:

1. 10 cm
2. 20/√2 cm
3. 40 cm
4. 5 cm

Question 68 · Physics · Oscillations

The SI unit of angular frequency is:

1. Hz
2. rad s⁻¹
3. m s⁻¹
4. rad

Question 69 · Physics · Electromagnetic Induction

The SI unit of magnetic flux is:

1. Tesla
2. Henry
3. Weber
4. Volt

Question 70 · Physics · Moving Charges and Magnetism

A proton enters a uniform magnetic field of magnitude B with velocity v making an angle of 60° with the magnetic field. The radius of the helical path described by the proton is:

1. mv/eB
2. mv/2eB
3. √3mv/2eB
4. mv√3/eB

Question 71 · Physics · Ray Optics and Optical Instruments

The power of a convex lens of focal length 50 cm is:

1. +1 D
2. +2 D
3. +5 D
4. -2 D

Question 72 · Physics · Electromagnetic Waves

The electric field and magnetic field vectors in an electromagnetic wave are:

1. Parallel to each other
2. Perpendicular to each other and to the direction of propagation
3. Parallel to the direction of propagation
4. At an angle of 45° to each other

Question 73 · Physics · Wave Optics

Assertion (A): Huygens' principle successfully explains the laws of reflection and refraction of light. Reason (R): Every point on a wavefront acts as a source of secondary wavelets which spread in all directions with the speed of light in that medium.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Question 74 · Physics · Semiconductor Electronics: Materials, Devices and Simple Circuits

Which one of the following logic gates is called the 'universal gate'?

1. AND gate only
2. OR gate only
3. NAND gate
4. XOR gate

Question 75 · Physics · Atoms

Assertion (A): Rutherford's α-particle scattering experiment established that most of the mass of an atom is concentrated in a very small central region. Reason (R): A very small fraction of α-particles suffered large-angle scattering or rebounded after striking the nucleus.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Question 76 · Zoology · Structural Organisation in Animals

The basement membrane underlying epithelial tissue is destroyed experimentally. Which immediate consequence is most likely to occur?

1. Loss of epithelial attachment and support
2. Loss of blood supply to muscles
3. Increased erythropoiesis
4. Formation of cartilage

Question 77 · Zoology · Structural Organisation in Animals

A connective tissue contains chondrocytes enclosed within lacunae and lacks blood vessels. Which property best explains its slow healing following injury?

1. Presence of collagen fibres
2. Absence of fibroblasts
3. Avascular nature
4. Presence of elastic fibres

Question 78 · Zoology · Human Health and Disease

Which of the following diseases is diagnosed using the Widal test?

1. Tuberculosis
2. Typhoid
3. Malaria
4. AIDS

Question 79 · Zoology · Chemical Coordination and Integration

Which cells of the pancreatic islets secrete glucagon?

1. Alpha cells
2. Beta cells
3. Delta cells
4. PP cells

Question 80 · Zoology · Human Health and Disease

Which of the following best differentiates a malignant tumour from a benign tumour?

1. Presence of blood vessels
2. Ability to invade surrounding tissues and metastasize
3. Slow cell division
4. Formation of a connective tissue capsule

Question 81 · Zoology · Body Fluids and Circulation

A patient has complete destruction of the atrioventricular (AV) valves while the semilunar valves remain intact. Which event will occur during ventricular systole?

1. Blood will flow efficiently into the aorta and pulmonary artery only.
2. Blood will regurgitate from the ventricles into the atria.
3. Blood will not enter the ventricles during ventricular diastole.
4. The semilunar valves will remain permanently closed.

Question 82 · Zoology · Human Reproduction

A man has normal testosterone levels but is infertile because spermatozoa are absent in the semen. Examination reveals complete destruction of Sertoli cells while Leydig cells remain functional. Which function has been primarily affected?

1. Secretion of testosterone
2. Nourishment and support of developing germ cells during spermatogenesis
3. Secretion of LH
4. Production of seminal plasma by the prostate gland

Question 83 · Zoology · Animal Kingdom

A multicellular animal possesses a cellular level of organization, intracellular digestion, numerous pores in the body wall and a canal system. Which feature alone distinguishes it from all eumetazoans?

1. Diploblastic body organization
2. Presence of choanocytes
3. Radial symmetry
4. Mesoglea between tissue layers

Question 84 · Zoology · Biotechnology: Principles and Processes

A researcher inserts a eukaryotic gene directly into a bacterial expression vector without removing introns. Although transformation is successful, no functional protein is produced. What is the most appropriate explanation?

1. Bacteria cannot replicate recombinant plasmids.
2. Bacteria lack the machinery required to remove introns from pre-mRNA.
3. Restriction enzymes destroy the inserted gene after transformation.
4. DNA ligase prevents transcription of recombinant DNA.

Question 85 · Zoology · Chemical Coordination and Integration

Which hormone is secreted by the zona fasciculata of the adrenal cortex?

1. Aldosterone
2. Cortisol
3. Adrenaline
4. Noradrenaline

Question 86 · Zoology · Reproductive Health

Which of the following contraceptive methods primarily prevents fertilization by acting as a physical barrier between sperm and ovum?

1. Copper-T
2. Condom
3. Oral contraceptive pills
4. LNG-20

Question 87 · Zoology · Principles of Inheritance and Variation

A pea plant with genotype Tt is self-pollinated. What is the probability of obtaining a dwarf offspring?

1. 0%
2. 25%
3. 50%
4. 75%

Question 88 · Zoology · Biotechnology and its Applications

A child suffering from Adenosine Deaminase (ADA) deficiency receives gene therapy by introducing a functional ADA gene into cultured lymphocytes. The treatment initially improves immunity but repeated treatments are required. What is the most appropriate explanation?

1. The introduced gene is permanently incorporated into germ cells.
2. Lymphocytes have a limited lifespan and are gradually replaced.
3. The ADA gene is immediately destroyed by restriction enzymes.
4. PCR removes the inserted ADA gene after therapy.

Question 89 · Zoology · Reproduction in Organisms

Which one of the following statements correctly distinguishes life span from reproduction?

1. Every organism reproduces before completing its life span.
2. Life span refers to the period between birth and natural death, whereas reproduction is the biological process of producing offspring.
3. Life span and reproduction are identical biological phenomena.
4. All organisms reproduce only once during their life span.

Question 90 · Zoology · Evolution

A small population of birds colonizes an isolated island after a cyclone. Over thousands of generations, they evolve into several species with different beak shapes adapted to distinct food sources. Which combination of evolutionary mechanisms best explains this observation?

1. Convergent evolution followed by genetic equilibrium
2. Adaptive radiation driven by natural selection
3. Analogous evolution due to gene flow
4. Industrial melanism caused by mutation alone

Question 91 · Zoology · Neural Control and Coordination

Which of the following types of neurons carries impulses from receptors to the central nervous system?

1. Motor neuron
2. Sensory (Afferent) neuron
3. Interneuron
4. Multipolar neuron

Question 92 · Zoology · Excretory Products and their Elimination

Assertion (A): The loop of Henle is essential for producing hyperosmotic urine. Reason (R): It establishes a corticomedullary osmotic gradient through the counter current mechanism.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Question 93 · Zoology · Molecular Basis of Inheritance

A mutation changes the sequence of a single nucleotide in the β-globin gene, resulting in substitution of valine for glutamic acid. Which type of mutation is this?

1. Frameshift mutation
2. Chromosomal mutation
3. Point mutation
4. Deletion mutation

Question 94 · Zoology · Microbes in Human Welfare

A farmer inoculates legume seeds with Rhizobium but also applies a large amount of nitrogen fertilizer throughout the growing season. Which outcome is most likely?

1. Root nodulation and biological nitrogen fixation will be enhanced.
2. Root nodulation and nitrogen fixation will be suppressed due to readily available combined nitrogen.
3. Rhizobium will convert into a pathogen.
4. Methanobacterium will replace Rhizobium in root nodules.

Question 95 · Zoology · Biodiversity and Conservation

According to NCERT, which biodiversity hotspot includes India's Nicobar Islands?

1. Indo-Burma
2. Western Ghats–Sri Lanka
3. Sundaland
4. Himalaya

Question 96 · Zoology · Breathing and Exchange of Gases

Assertion (A): During quiet inspiration, the diaphragm contributes more to the increase in thoracic volume than the external intercostal muscles. Reason (R): Contraction of the diaphragm increases the vertical diameter of the thoracic cavity.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Question 97 · Zoology · Locomotion and Movement

A skeletal muscle fibre is experimentally treated with a drug that completely blocks the release of Ca²⁺ from the sarcoplasmic reticulum without affecting ATP production or action potential generation. Which of the following events will still occur?

1. Binding of myosin heads to actin filaments
2. Movement of tropomyosin away from active sites on actin
3. Propagation of action potential along the sarcolemma and T-tubules
4. Power stroke leading to shortening of the sarcomere

Question 98 · Zoology · Organisms and Populations

An orchid growing on the branch of a mango tree is an example of:

1. Mutualism
2. Commensalism
3. Parasitism
4. Competition

Question 99 · Zoology · Ecosystem

Assertion (A): Decomposers are indispensable components of an ecosystem. Reason (R): They recycle nutrients by breaking down dead organic matter into inorganic substances that can be reused by producers.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.

Question 100 · Zoology · Environmental Issues

Assertion (A): Electrostatic precipitators are highly efficient in removing particulate matter from industrial exhaust. Reason (R): They electrically charge dust particles and collect them on oppositely charged plates.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.