KCET 2022 Biology D3 Question Paper With Answer Key And Solutions PDF

Step 1: Mendelian disorders → single gene mutations (autosomal/X-linked).
Step 2:
- Thalassemia, Cystic fibrosis, Haemophilia → gene mutations → Mendelian.
- Down's syndrome → trisomy 21 → chromosomal aneuploidy → non-Mendelian.
Hence, (D) is correct. Quick Tip: - Mendelian: Sickle cell, CF, Haemophilia - Non-Mendelian: Down’s, Turner’s, Klinefelter’s (chromosomal)

Step 1: Klinefelter’s syndrome → XXY male.
Step 2: Symptoms:
- Tall, sterile, gynecomastia (breast development due to estrogen excess).
Step 3: Turner’s (XO) → female; others → no gynecomastia.
Hence, (D) is correct. Quick Tip: - Klinefelter’s (XXY): Male + gynecomastia - Turner’s (XO): Female, webbed neck

Step 1: Standard pedigree symbols:
- Male → square
- Female → circle
- Affected → shaded/filled
Step 2: Affected male → shaded square (■).
Hence, (A) is correct. Quick Tip: - Pedigree: – Male normal: □ – Male affected: ■ – Female normal: ○ – Female affected: ●

Step 1: Diagram shows DNA wrapped around histone core.
Step 2: This is "beads on a string" → nucleosome (basic chromatin unit).
Step 3:
- Mesosome: Bacterial
- Chromosome: Condensed
- Ribosome: Protein synthesis
Hence, nucleosome. Quick Tip: - Nucleosome: DNA + histone octamer (2 each H2A, H2B, H3, H4) - 11 nm fiber

Step 1: Placental hormones:
- hCG, hPL, progesterone, estrogen, relaxin.
Step 2: FSH → anterior pituitary → stimulates follicles.
Hence, not secreted by placenta. Quick Tip: - Placenta: hCG, Progesterone, Relaxin - Pituitary: FSH, LH

Step 1:
- Bulbil: Vegetative bud → Agave (correct).
- Gemmules: Sponges
- Conidia: Fungi (Penicillium)
- Spores: Ferns, fungi
Hence, only (A) is correct. Quick Tip: - Bulbil: Agave, Onion - Gemmule: Sponge - Conidia: Aspergillus

Step 1:
- ART → Assisted Reproductive Technology (IVF, IUI, ZIFT, GIFT).
- RCH: Program
- MTP: Abortion
- RTI: Infection
Step 2: For infertility → ART.
Hence, (D). Quick Tip: - Infertility: ART (IVF, ICSI) - Contraception: MTP

Step 1: Amniocentesis → amniotic fluid sampling (16–18 weeks).
Step 2: Fetal cells → karyotyping → sex determination, genetic disorders.
Step 3: Heart/brain → ultrasound; culture → secondary.
Hence, primary → sex & genetics. Quick Tip: - Amniocentesis: Fetal karyotype - Banned for sex selection in India

Step 1: Homo habilis (2.4–1.4 mya) → first in Homo genus.
Step 2: "Handy man" → used stone tools.
Step 3:
- H. erectus: Fire, upright
- H. sapiens: Modern
Hence, first human-like → H. habilis. Quick Tip: - Evolution: Australopithecus → H. habilis → H. erectus → H. sapiens

Step 1:
- XY: Male = XY (heterogametic)
- XO: Male = XO (heterogametic)
Step 2: In both, male produces two gamete types (X/Y or X/O).
Step 3: Female → XX (homogametic).
Hence, male heterogamety. Quick Tip: - Male heterogamety: XY, XO - Female heterogamety: ZW (birds)

Step 1: Anabolic steroids → synthetic testosterone.
Step 2: In females → androgenic effects:
- Deep voice
- Facial hair
- Enlarged clitoris → masculinisation.
Step 3: Liver damage possible, but masculinisation is primary in females.
Hence, (B). Quick Tip: - Females + steroids: Virilization (masculinisation) - Males: Gynecomastia, infertility

Step 1: Opiates → from opium poppy.
Step 2:
- Morphine, Heroin, Codeine → opiates.
- Amphetamines: Stimulants
- LSD: Hallucinogen
- Barbiturates: Sedatives
Hence, morphine. Quick Tip: - Opiates: Morphine, Heroin - Cannabinoids: THC - Cocaine: Stimulant

Step 1: Swiss cheese → Propionibacterium shermanii.
Step 2: Ferments lactate → propionic acid + CO₂.
Step 3: CO₂ bubbles → large holes (eyes).
Step 4: Not methane, fungus, or machine.
Hence, (A). Quick Tip: - Swiss cheese eyes: CO₂ from Propionibacterium - Roquefort: Penicillium (blue veins)

Step 1: LAB → Lactobacillus in curd.
Step 2: Synthesizes Vitamin B₁₂ (cobalamin) during fermentation.
Step 3:
- Vitamin C → destroyed by heat
- Vitamin E → not microbial
- Vitamin B → vague
Hence, B₁₂. Quick Tip: - Curd: ↑ B₁₂, B₂, folate - Yogurt: Probiotic + vitamins

Step 1: Oily stains → lipids.
Step 2: Lipase → hydrolyzes fats → glycerol + fatty acids.
Step 3:
- Amylase: Starch
- Renin: Milk clotting
- Protease: Proteins
Hence, lipase. Quick Tip: - Detergent enzymes: – Lipase → Oil – Protease → Blood – Amylase → Food

Step 1: Meselson & Stahl (1958) → E. coli.
Step 2: \(^{15}\)N → \(^{14}\)N → hybrid DNA.
Step 3: Okazaki fragments → lagging strand → semicontinuous.
Hence, E. coli. Quick Tip: - Semiconservative: Meselson-Stahl - Semicontinuous: Okazaki (lagging strand)

Step 1: Griffith → S (smooth) and R (rough) strains.
Step 2: Heat-killed S + live R → virulent mice.
Step 3: Transforming principle → DNA.
Hence, S. pneumoniae. Quick Tip: - Griffith (1928): Transformation - Avery (1944): DNA is genetic material

Step 1: Total codons = \(4^3 = 64\).
Step 2:
- 3 stop codons: UAA, UAG, UGA
- 61 sense codons → 20 amino acids (degenerate).
Hence, 61. Quick Tip: - 64 total - 61 code aa - 3 stop - AUG: Start + Met

Step 1: DNA fingerprinting → VNTRs (Variable Number Tandem Repeats).
Step 2: Satellite DNA → highly repetitive, variable repeats.
Step 3: Unique pattern per individual.
Hence, (A). Quick Tip: - VNTRs/Minisatellites → DNA fingerprinting - Alec Jeffreys (1984)

Step 1: P. falciparum → cerebral malaria, high parasitemia.
Step 2: Causes blackwater fever, organ failure.
Step 3: Most fatal (WHO).
Hence, (A). Quick Tip: - P. falciparum: Malignant tertian, fatal - P. vivax: Benign tertian, relapsing

Step 1: Allergic reaction → Type I hypersensitivity.
Step 2: Mediated by IgE bound to mast cells/basophils.
Step 3: Allergen → cross-links IgE → histamine release → allergy.
Step 4:
- IgG, IgM: Immunity
- IgA: Mucosal
Hence, IgE. Quick Tip: - Allergy: IgE → Mast cell degranulation - Anaphylaxis: Severe IgE reaction

Step 1: ADA deficiency → SCID (no T/B cells).
Step 2: Bone marrow → source of hematopoietic stem cells → produce healthy lymphocytes.
Step 3: First gene therapy → ADA gene into lymphocytes.
Hence, bone-marrow transplantation. Quick Tip: - ADA deficiency: SCID - Cure: Bone marrow transplant / Gene therapy

Step 1: Population change = (Births + Immigration) – (Deaths + Emigration)
Step 2:
- Births = 25
- Immigration = 2
- Deaths = 24
- Emigration = 3
Step 3: \[ \Delta P = (25 + 2) - (24 + 3) = 27 - 27 = 0 \]
Hence, net increase = 0. Quick Tip: - Population growth: \(\Delta P = (B + I) - (D + E)\) - Zero growth: \(B + I = D + E\)

Step 1: Molecular scissors → cut DNA at specific sites.
Step 2: Restriction enzymes (e.g., EcoRI) → recognize palindromes → cleave.
Step 3: Used in cloning.
Step 4: Polymerases → synthesize, not cut.
Hence, restriction enzyme. Quick Tip: - Restriction enzyme → "Molecular scissors" - DNA ligase → "Molecular glue"

Step 1: Sequence: \(5'\)-GAATTC-\(3'\) \(3'\)-CTTAAG-\(5'\)
Step 2: Reads same on complementary strand in reverse → palindrome.
Step 3: Recognized by EcoRI.
Hence, palindromic sequence. Quick Tip: - Palindrome: 5'-GAATTC-3' = 3'-CTTAAG-5' - EcoRI cuts between G and A

Step 1: Agarose gel → DNA migrates to anode (negative charge).
Step 2: Smaller fragments move faster.
Step 3:
- Cutting → restriction enzyme
- Joining → ligase
- Isolation → extraction
Hence, separation by size. Quick Tip: - Gel electrophoresis: – Small DNA → far – Large DNA → near well

Step 1: Vector → ampᵣ gene.
Step 2: Only transformed cells grow on ampicillin.
Step 3: Non-recombinants also grow → use insertional inactivation.
Hence, first selects transformants. Quick Tip: - Selectable marker: ampᵣ → transformants - Blue-white: X-gal → recombinants (white)

Step 1: RNAi → dsRNA introduced.
Step 2: Dicer → cuts → siRNA.
Step 3: RISC → degrades target mRNA.
Step 4: SSRN → not a term.
Hence, dsRNA. Quick Tip: - RNAi: dsRNA → Dicer → siRNA → RISC → mRNA cleavage

Step 1: Cry-IAC → Bt toxin.
Step 2: Targets lepidopteran larvae (moths/butterflies).
Step 3: Cotton bollworm (Helicoverpa) → lepidopteran.
Step 4:
- Cry-IIAB: Nematodes
- Corn borer: Different Cry gene
Hence, cotton bollworms. Quick Tip: - Cry-I: Lepidoptera (bollworm) - Cry-II: Diptera + Lepidoptera - Cry-III: Coleoptera

Step 1: PM₂.₅ → particles < 2.5 μm in diameter.
Step 2: Small size → penetrate deep into lungs → alveoli → enter bloodstream.
Step 3: Cause cardiovascular disease, lung cancer, COPD.
Step 4: PM₁₀ (>2.5 μm) → trapped in upper airways.
Hence, < 2.5 μm → greatest risk. Quick Tip: - PM₂.₅: < 2.5 μm → alveoli + blood - PM₁₀: < 10 μm → nose/throat - WHO: PM₂.₅ < 10 μg/m³ (annual mean)

Step 1: Homeostasis → maintaining stable internal conditions (pH, temperature, ions, glucose).
Step 2:
- Thermoregulation: Temperature
- Osmoregulation: Water/salt balance
- Metastasis: Cancer spread
Step 3: Homeostasis encompasses all.
Hence, homeostasis. Quick Tip: - Homeostasis → "Same standing" (Walter Cannon) - Negative feedback: Most common

Step 1:
- Diurnal: Active during day (e.g., humans, eagles).
- Nocturnal: Night (owls)
- Crepuscular: Dawn/dusk (rabbits)
Step 2: Vesporal, Cresporal, Auroral → not standard terms.
Hence, diurnal. Quick Tip: - Diurnal → Day - Nocturnal → Night - Crepuscular → Twilight

Step 1: Deserts: High temperature + very low rainfall (<25 cm/year).
Step 2: (D) says more rainfall + low temperature → incorrect.
Step 3:
- (A): Grasslands → moderate rain, warm
- (B): Tundra → cold, low precipitation
- (C): Temperature + precipitation → biome distribution
Hence, (D) is incorrect. Quick Tip: - Desert: Hot, arid - Tundra: Cold, arid - Rainforest: Hot, wet

Step 1: PAR (400–700 nm) → ~50% of solar radiation.
Step 2: Plants capture 2–10% of PAR for GPP.
Step 3: Most energy lost: reflection, heat, transmission.
Step 4: NPP → ~1–2% of solar energy.
Hence, 2–10%. Quick Tip: - PAR: 50% solar - GPP: 2–10% of PAR - NPP: 0.2–2% solar

Step 1: Equation: \( S = cA^Z \)
- \( S \): Species richness
- \( A \): Area
- \( c, Z \): Constants
Step 2: Species-area relationship (Alexander von Humboldt).
Step 3: Log form: \(\log S = \log c + Z \log A\) → straight line.
Hence, species-area relationship. Quick Tip: - \( S = cA^Z \) → Species-area curve - Z: 0.1–0.2 (mainland), 0.6–1.0 (islands)

Step 1: Cuscuta (dodder) → yellow, leafless vine.
Step 2: Attaches externally to host stem → haustoria penetrate → absorb nutrients.
Step 3:
- Ectoparasite: Lives outside host
- Endoparasite: Inside
- Brood parasitism: Cuckoo
Hence, ectoparasitism. Quick Tip: - Cuscuta: Stem holoparasite → ectoparasite - Rafflesia: Root endoparasite

Step 1: Cell Theory (1838–1839):
- M.J. Schleiden → all plants made of cells.
- Theodor Schwann → all animals made of cells.
Step 2: Postulates:
1. All living organisms composed of cells.
2. Cell is basic unit of life.
Step 3: Virchow (1855): "Omnis cellula-e-cellula".
Hence, Schleiden and Schwann. Quick Tip: - Cell Theory: – Schleiden (1838): Plants – Schwann (1839): Animals – Virchow: Cell division

Step 1: Cotton fiber → seed hair of Gossypium.
Step 2: >90% cellulose (β-1,4-glucan).
Step 3:
- Glycogen: Animal storage
- Starch: Plant storage
- Inulin: Fructan (dahlia)
Hence, cellulose. Quick Tip: - Cotton: Cellulose (95%) - Wool: Protein - Jute: Lignin + cellulose

Step 1: Crossing over → pachytene of meiosis.
Step 2: Recombinase (Spo11, RAD51) → forms Holliday junction.
Step 3:
- Endonuclease → cuts
- Ligase → joins
- Polymerase → fills
But recombinase initiates.
Hence, recombinase. Quick Tip: - Crossing over: – Synaptonemal complex → Recombinase → Chiasma

Step 1: Kranz anatomy → C4 plants.
Step 2:
- Bundle sheath with chloroplasts
- Mesophyll radial
Step 3: Maize → C4; others → C3.
Hence, maize. Quick Tip: - Kranz: C4 (maize, sugarcane) - C3: Pea, tomato, potato

Step 1: RQ = \(\frac{CO_2}{O_2}\)
Step 2: Glucose: \[ C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O \]
Step 3: \[ RQ = \frac{6}{6} = 1.0 \]
Hence, 1.0. Quick Tip: - RQ: – Carbs: 1.0 – Fats: 0.7 – Proteins: 0.9 – Anaerobic: ∞

Step 1: Epiglottis → flap over larynx.
Step 2: Closes during swallowing → food to esophagus.
Step 3: If fails → food in trachea → cough reflex.
Hence, epiglottis. Quick Tip: - Swallowing: – Epiglottis closes larynx – Peristalsis → esophagus

Step 1: Binomial → Genus + species.
Step 2: Linnaeus → "Species Plantarum" (1753), "Systema Naturae" (1758).
Step 3:
- Bentham & Hooker → classification
- John Ray → early binomial
Hence, Linnaeus. Quick Tip: - Binomial: Linnaeus - ICBN/ICZN: Rules - Homo sapiens: Linnaeus

Step 1: BSE → Mad Cow Disease.
Step 2: Caused by prions → misfolded PrP.
Step 3: No nucleic acid → resistant.
Step 4: vCJD in humans.
Hence, prions. Quick Tip: - Prions: – BSE, CJD, Kuru, Scrapie – Protein only

Step 1: Red algae (Rhodophyta):
- Phycoerythrin (red pigment)
- Floridean starch (storage)
Step 2:
- Brown: Fucoxanthin
- BGA: Phycocyanin
- Green: Chlorophyll a,b
Hence, red algae. Quick Tip: - Red algae: – Phycoerythrin – Floridean starch – Agar, carrageenan

Step 1: Arthropods:
- Gills: Crabs
- Book gills: Horseshoe crab
- Book lungs: Scorpions
- Trachea: Insects
Step 2: Others lack diversity.
Hence, arthropods. Quick Tip: - Arthropod respiration: – Gills, book gills, book lungs, trachea

Step 1: Colchicine → from Colchicum autumnale (autumn crocus).
Step 2: Inhibits spindle → polyploidy.
Hence, Colchicum. Quick Tip: - Colchicine: Colchicum autumnale - Use: Polyploidy, gout

Step 1: Setae → locomotion.
Step 2: Absent in:
- 1st segment
- Last segment
- Clitellum (14–16)
Step 3: Clitellum → cocoon formation.
Hence, first, last, clitellum. Quick Tip: - Earthworm setae: – Absent: 1st, last, 14–16 – S-shaped, 4 pairs/segment

Step 1: Ovule → integumented megasporangium.
Step 2:
- Megasporangium → produces megaspores.
- Megaspore mother cell → diploid cell inside.
- Megaspore → haploid product.
- Megasporophyll → carpel.
Step 3: Ovule = megasporangium + integuments.
Hence, megasporangium. Quick Tip: - Ovule = Megasporangium - Nucellus = Megasporangium tissue

Step 1: Polygonum type (common):
- 3 antipodals
- 2 synergids
- 1 egg cell
- 1 central cell (2 polar nuclei → fuse → 1 nucleus)
Step 2: Total 8 cells, 7 nuclei.
Hence, 7 nucleated, 8 celled. Quick Tip: - Embryosac: – 8 cells – 7 nuclei (central cell: 2n → 1 nucleus)

Step 1: Date palm (Phoenix dactylifera) seed → ~2000 years old.
Step 2: Excavated at Masada, Israel → germinated in 2005.
Step 3: Named "Methuselah".
Hence, Phoenix dactylifera. Quick Tip: - Oldest viable seed: Date palm (2000 yrs) - Lupin: Arctic (10,000 yrs, unconfirmed)

Step 1: Spermatogenesis requires 2–3°C below body temperature (35°C).
Step 2: Scrotum → thermoregulation via pampiniform plexus, cremaster muscle.
Step 3: Hormone, storage, release → not primary reason.
Hence, low temperature. Quick Tip: - Scrotum: 35°C for sperm - Cryptorchidism: Undescended → infertility

Step 1: Infundibulum, Fimbriae, Isthmus → parts of fallopian tube.
Step 2: Labia minora → external genitalia (vulva).
Hence, labia minora is odd. Quick Tip: - Fallopian tube: – Fimbriae → Infundibulum → Ampulla → Isthmus

Step 1: Quickening → first fetal movement → 18–20 weeks (~5th month).
Step 2: Lanugo (fine hair) → appears on head → 5th month.
Step 3: 4th month → limbs form; 8th → fat deposition.
Hence, 5th month. Quick Tip: - 5th month: Quickening + Lanugo - 7–8th month: Lanugo sheds

Step 1: WBC differential:
- Neutrophils: 50–70%
- Lymphocytes: 20–40%
- Monocytes: 2–8%
- Eosinophils: 1–4%
- Basophils: 0.5–1%
Step 2: Neutrophils → first responders.
Hence, most abundant. Quick Tip: - WBC order: Neutrophils > Lymphocytes > Monocytes > Eosinophils > Basophils ("Never Let Monkeys Eat Bananas")

Step 1: Ultrafiltration → glomerulus (Bowman’s capsule).
Step 2: High pressure → plasma filters → filtrate.
Step 3:
- PCT/DCT → reabsorption
- Collecting duct → concentration
Hence, glomerulus. Quick Tip: - Glomerulus: Filtration - PCT: 65% reabsorption - Loop of Henle: Concentration

Step 1: Corpus callosum → white matter bundle.
Step 2: Connects left and right cerebral hemispheres.
Step 3: Allows interhemispheric communication.
Hence, two cerebral hemispheres. Quick Tip: - Corpus callosum: Left ↔ Right cerebrum - Split-brain: Severed → no communication

Step 1: Menstrual cycle → uterine bleeding if no pregnancy.
Step 2: Seen in higher primates: humans, apes, Old World monkeys.
Step 3: Others → estrous cycle (no bleeding).
Hence, apes.

Step 1: Dioecious → male and female flowers on separate plants.
Step 2: Papaya → male, female, hermaphrodite plants.
Step 3: Others → monoecious or bisexual.
Hence, papaya. Quick Tip: - Dioecious: Papaya, Date palm - Monoecious: Cucurbita, Coconut

Step 1: Stamen = anther + filament.
Step 2: Filament → stalk supporting anther.
Step 3:
- Petiole: Leaf stalk
- Peduncle: Inflorescence stalk
- Pedicel: Flower stalk
Hence, filament. Quick Tip: - Stamen: Filament (stalk) + Anther - Pollen sac → inside anther