KCET 2022 Biology C1 Question Paper With Answer Key And Solutions PDF

Step 1: DNA fingerprinting uses VNTRs (Variable Number Tandem Repeats) in satellite DNA.

Step 2: These are highly repetitive, non-coding regions with variable repeat lengths.

Step 3: Produce unique banding patterns after restriction digestion and gel electrophoresis. Quick Tip: Alec Jeffreys (1984) → father of DNA fingerprinting.

Step 1: P. falciparum causes malignant tertian malaria.

Step 2: High parasitemia, cytoadherence → cerebral malaria.

Step 3: Highest mortality rate. Quick Tip: Falciparum → ring forms, banana gametocytes.

Step 1: Type I hypersensitivity → mediated by IgE.

Step 2: Binds to mast cells → histamine release on allergen exposure.

Step 3: Causes asthma, hay fever, anaphylaxis. Quick Tip: Desensitization → allergen immunotherapy.

Step 1: Anabolic steroids → synthetic androgens.

Step 2: In females → virilization: hirsutism, voice deepening, clitoral enlargement.

Step 3: Liver damage possible but not gender-specific. Quick Tip: Nandrolone, stanozolol → common anabolic steroids.

Step 1: Opiates → derived from opium (Papaver somniferum).

Step 2: Morphine → principal alkaloid → analgesic, sedative.

Step 3: LSD (hallucinogen), amphetamines (stimulant), barbiturates (sedative). Quick Tip: Codeine, heroin → semi-synthetic opiates.

Step 1: Propionibacterium shermanii used in Swiss cheese.

Step 2: Ferments lactate → propionic acid + CO₂.

Step 3: CO₂ trapped → forms eyes (holes). Quick Tip: Emmental cheese → large eyes.

Step 1: Lactic Acid Bacteria (LAB) synthesize B₁₂ during milk fermentation.

Step 2: Curd → rich source of cobalamin.

Step 3: Important for vegetarians. Quick Tip: Yogurt → probiotic + B₁₂.

Step 1: Oily stains → triglycerides.

Step 2: Lipase hydrolyzes fats → glycerol + fatty acids.

Step 3: Used in biological detergents. Quick Tip: Tide, Ariel → contain lipase, protease.

Step 1: Meselson-Stahl experiment (1958).

Step 2: Used E. coli with ¹⁵N (heavy) → switched to ¹⁴N.

Step 3: Density gradient → hybrid band → semiconservative. Quick Tip: Conservative, dispersive → ruled out.

Step 1: Griffith’s transformation experiment.

Step 2: S strain (virulent) + heat-killed S + R strain → virulent mice.

Step 3: Transforming principle = DNA (later proved). Quick Tip: Avery, MacLeod, McCarty (1944) → DNA is genetic material.

Step 1: Total codons = 4³ = 64.

Step 2: 3 stop codons (UAA, UAG, UGA).

Step 3: 61 codons code for 20 amino acids (degenerate code). Quick Tip: AUG → start + methionine.

Step 1: Antibiotic resistance gene (e.g., amp\^R) is a selectable marker in vectors.

Step 2: Only transformed cells (that uptake plasmid) survive on antibiotic medium.

Step 3: Non-transformed cells die → selection of transformed cells. Quick Tip: Blue-white screening → insertional inactivation.

Step 1: RNA interference (RNAi) → gene silencing.

Step 2: dsRNA is processed by Dicer → siRNA.

Step 3: siRNA + RISC → degrades target mRNA. Quick Tip: RNAi → natural defense against viruses.

Step 1: Cry-IAC → Bt toxin from Bacillus thuringiensis.

Step 2: Toxic to lepidopteran larvae (bollworm).

Step 3: Used in Bt cotton. Quick Tip: Cry-IAc, Cry-IAb → bollworm; Cry-IIAb → corn borer.

Step 1: ADA deficiency → SCID (no T-cells).

Step 2: Bone marrow contains stem cells → produce ADA enzyme.

Step 3: Bone marrow transplant restores immunity. Quick Tip: First gene therapy (1990) → ADA deficiency.

Step 1: Net change = (Births + Immigration) – (Deaths + Emigration)

Step 2: = (25 + 2) – (24 + 3) = 27 – 27 = 0

Step 3: Natural increase = 1; Net migration = –1 → 0 Quick Tip: ΔP = (B – D) + (I – E)

Step 1: Restriction enzymes cut DNA at specific sites.

Step 2: Called molecular scissors in genetic engineering.

Step 3: e.g., EcoRI, HindIII. Quick Tip: Sticky ends → cohesive ends.

Step 1: Sequence reads same forward and backward on complementary strands.

Step 2: 5'-GAATTC-3' = 3'-CTTAAG-5' reversed → palindrome.

Step 3: Recognition site for EcoRI. Quick Tip: Palindrome → symmetry in DNA.

Step 1: Agarose gel + electric field.

Step 2: DNA (–ve charge) moves to anode.

Step 3: Smaller fragments move faster → size-based separation. Quick Tip: Ethidium bromide → UV visualization.

Step 1: PAR (Photosynthetically Active Radiation) = 400–700 nm.

Step 2: Plants capture only 2–10% of incident solar energy.

Step 3: Most lost as heat, reflection, or unused wavelengths. Quick Tip: Only ~1% of solar energy reaches Earth; plants use fraction of PAR.

Step 1: Equation S = cA\^z → species-area relationship (Humboldt).

Step 2: S = species richness, A = area.

Step 3: Log form: log S = log c + z log A → straight line. Quick Tip: z = 0.1–0.2 (mainland), 0.2–0.3 (islands).

Step 1: Cuscuta (dodder) → parasitic plant.

Step 2: Grows externally on host → haustoria penetrate phloem.

Step 3: Ectoparasite (outside host body). Quick Tip: Cuscuta → yellow twining stem, no chlorophyll.

Step 1: PM2.5 (≤2.5 μm) → fine particulates.

Step 2: Enter alveoli, bloodstream.

Step 3: Cause asthma, COPD, heart disease → highest risk. Quick Tip: PM10 → upper airways; PM2.5 → deep lungs.

Step 1: Homeostasis → stable internal conditions.

Step 2: Includes temperature, pH, ion balance.

Step 3: Osmoregulation, thermoregulation → components of homeostasis. Quick Tip: Walter Cannon coined "homeostasis".

Step 1: Diurnal → active in daylight (e.g., humans, birds).

Step 2: Nocturnal → night; Crepuscular → dawn/dusk.

Step 3: Vesporal, auroral → not standard. Quick Tip: Diurnal animals have good color vision.

Step 1: Deserts → high temperature, <25 cm/year rainfall.

Step 2: Option (D) says more rainfall + low temperature → incorrect.

Step 3:
- Tundra: cold, low rain
- Grasslands: moderate rain, warm
- Biomes depend on temp + precipitation Quick Tip: Tropical rainforests → high rain + high temp.

Step 1: Arthropods show diverse respiratory organs:

- Gills (crustaceans)

- Book gills (horseshoe crabs)

- Book lungs (scorpions, spiders)

- Trachea (insects)

Step 2: No other phylum has all these.

Molluscs → ctenidia; Annelids → skin; Sponges → no organs. Quick Tip: Tracheae → air-filled tubes in insects.

Step 1: Colchicine → alkaloid from Colchicum autumnale (autumn crocus).

Step 2: Inhibits spindle formation → used in polyploidy induction.

Step 3: Not from tulip, aloe, or asparagus. Quick Tip: Colchicine → doubles chromosomes.

Step 1: Setae → locomotion in earthworm.

Step 2: Absent in:

- 1st segment (peristomium)

- Last segment (anal)

- Clitellum (14–16 segments, glandular)

Step 3: Option (A) correct. Quick Tip: Clitellum → cocoon secretion.

Step 1: M.J. Schleiden (1838) → plants made of cells.

Step 2: T. Schwann (1839) → animals made of cells.

Step 3: Cell theory (1839): all organisms cellular.

Robert Brown → nucleus (1831); Hooke → cell (1665). Quick Tip: Cell theory: 1. Cell = unit of life, 2. All organisms cellular.

Step 1: Cotton → cell wall of seed hairs.

Step 2: Plant cell wall → cellulose (β-1,4-glucose).

Step 3: Cotton ≈ 95% cellulose → textile fiber.

Starch (storage), glycogen (animal), insulin (hormone). Quick Tip: Humans lack cellulase → can't digest cellulose.

Step 1: Crossing over → pachytene of meiosis.

Step 2: Recombinase (e.g., DMC1, RAD51) → strand exchange.

Step 3: Forms chiasmata → recombination.

Endonuclease → cuts DNA; ligase → seals. Quick Tip: Synaptonemal complex → holds homologues.

Step 1: Kranz anatomy → C4 plants.

Step 2: Bundle sheath cells with chloroplasts.

Step 3: Maize → C4; Pea, tomato, potato → C3. Quick Tip: C4 → Hatch-Slack pathway → high efficiency.

Step 1: RQ = CO₂ / O₂

Step 2: Glucose: C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O

Step 3: RQ = 6/6 = 1.0

Fats → 0.7; proteins → 0.9. Quick Tip: RQ > 1 → anaerobic respiration.

Step 1: Epiglottis → cartilage flap over trachea.

Step 2: Closes during swallowing → prevents food entry.

Step 3: Improper closure → food in windpipe → cough reflex. Quick Tip: Choking → Heimlich maneuver.

Step 1: Carolus Linnaeus → Species Plantarum (1753).

Step 2: Binomial: Genus + species.

Step 3: Universal system → e.g., Homo sapiens. Quick Tip: ICBN → plants; ICZN → animals.

Step 1: BSE (Mad Cow) → neurodegenerative.

Step 2: Caused by prions (PrP\^Sc) → misfolded proteins.

Step 3: No nucleic acid → infects brain. Quick Tip: Prions → CJD, Kuru, Scrapie.

Step 1: Red algae → phycoerythrin (red pigment).

Step 2: Store floridean starch (α-1,4-glucan).

Step 3: Deep water → absorb blue light. Quick Tip: Agar → Gelidium, Gracilaria.

Step 1: Menstrual cycle → shedding of uterine lining (bleeding).

Step 2: Seen in primates (humans, apes, monkeys).

Step 3: Cow, tiger, rat → estrous cycle (no menstruation). Quick Tip: Human cycle ≈ 28 days; apes similar.

Step 1: Dioecious → male and female flowers on separate plants.

Step 2: Papaya → male and female trees.

Step 3: Mango, cucurbita, coconut → monoecious. Quick Tip: Date palm → dioecious.

Step 1: Stamen = anther + filament.

Step 2: Filament → stalk supporting anther.

Step 3: Peduncle (inflorescence), pedicel (flower), petiole (leaf). Quick Tip: Androecium → stamens.

Step 1: Ovule = integumented megasporangium.

Step 2: Nucellus = megasporangium tissue.

Step 3: Produces megaspore from MMC. Quick Tip: Ovule → seed.

Step 1: Polygonum type → 7 cells: egg, 2 synergids, 3 antipodals, 1 central cell.

Step 2: Central cell → 2 polar nuclei → 8 nuclei total.

Step 3: 8-nucleated, 7-celled. Quick Tip: Female gametophyte = embryosac.

Step 1: Date palm seed from Masada (Israel).

Step 2: Germinated in 2005 → ~2000 years old.

Step 3: Oldest viable seed. Quick Tip: "Judean date palm" → extinct variety revived.

Step 1: Spermatogenesis needs 2–3°C below body temperature.

Step 2: Scrotum → external sac.

Step 3: Pampiniform plexus → heat exchange. Quick Tip: Cryptorchidism → infertility.

Step 1: Infundibulum, fimbriae, isthmus → fallopian tube.

Step 2: Labia minora → external genitalia (vulva).

Step 3: Odd one → labia minora. Quick Tip: Fallopian tube: infundibulum → ampulla → isthmus.

Step 1: Quickening → 5th month (mother feels movement).

Step 2: Lanugo (head hair) → 5th month.

Step 3: Heartbeat → 1st month; limbs → 8th week. Quick Tip: Gestation = 280 days ≈ 40 weeks.

Step 1: Neutrophils → 60–65% of WBCs.

Step 2: Phagocytic, first responders.

Step 3: Multilobed nucleus. Quick Tip: WBC count: 4,000–11,000/μL.

Step 1: Ultrafiltration → glomerulus.

Step 2: High pressure → plasma into Bowman’s capsule.

Step 3: Forms glomerular filtrate. Quick Tip: GFR ≈ 125 mL/min.

Step 1: Corpus callosum → white matter bundle.

Step 2: Connects left and right cerebral hemispheres.

Step 3: Enables inter-hemispheric communication. Quick Tip: Split-brain → corpus callosum sectioned.

Step 1: Amniocentesis → 15–20 weeks; amniotic fluid extracted.

Step 2: Fetal cells cultured → karyotyping.

Step 3: Detects sex (XX/XY), chromosomal disorders.

Banned for sex determination in India (PCPNDT Act). Quick Tip: Amniocentesis → diagnostic, not therapeutic.

Step 1: Homo habilis (2.4–1.4 mya) → earliest Homo.

Step 2: Brain ~650 cm³, Oldowan tools.

Step 3: "Handy man" → first human-like.

H. erectus → later (1.8 mya). Quick Tip: Evolution: Australopithecus → H. habilis → H. erectus → H. sapiens.

Step 1: XO-type (grasshopper): female XO → heterogametic.

Step 2: XY-type: male XY → heterogametic.

Step 3: Question focuses on XO → female heterogamety. Quick Tip: ZW (birds) → female heterogamety.

Step 1: Mendelian → single gene (thalassemia, haemophilia, CF).

Step 2: Down’s syndrome → trisomy 21 (nondisjunction).

Step 3: Chromosomal → non-Mendelian. Quick Tip: Non-Mendelian: chromosomal, polygenic, mitochondrial.

Step 1: Klinefelter’s (47, XXY) → male.

Step 2: Extra X → low testosterone, high estrogen → gynecomastia (breast development).

Step 3: Turner’s → female (XO). Quick Tip: Klinefelter: tall, sterile, gynecomastia.

Step 1: Pedigree symbols:

- Square → male

- Circle → female

- Filled → affected

Step 2: Affected male → filled square (■). Quick Tip: Carrier → half-filled.

Step 1: Nucleosome → DNA wrapped around histone octamer.

Step 2: H1 histone → linker between nucleosomes.

Step 3: Diagram shows DNA + H1 → nucleosome. Quick Tip: Beads-on-string → 11 nm fiber.

Step 1: Placenta secretes: hCG, hPL, progestogen, relaxin.

Step 2: FSH → anterior pituitary.

Step 3: Not placental. Quick Tip: hCG → pregnancy test.

Step 1: Bulbil → vegetative propagule in Agave.

Step 2: Gemmules → sponge; conidia → fungi.

Step 3: Correct → Bulbil – Agave. Quick Tip: Runner → grass; offset → Eichhornia.

Step 1: ART (Assisted Reproductive Technology) → IVF, IUI, ZIFT, GIFT.

Step 2: Treats infertility.

Step 3: MTP → abortion; RTI → infection; RCH → program. Quick Tip: First IVF baby: Louise Brown (1978).