Botany
- Which hormone promotes internode/petiole elongation in deep water rice? Answer: 4. Ethylene Key idea: In deep water rice, submergence raises ethylene levels, and ethylene promotes rapid elongation of internodes a... 1
- Family Fabaceae differs from Solanaceae and Liliaceae. With respect to the stamens, pick out the characteristics specific to family Fabaceae but not found in Solanaceae or Liliaceae. Answer: 2. Diadelphous and Dithecous anthers Key idea: Fabaceae has diadelphous stamens (9 + 1) with dithecous anthers. Solanaceae and Lilia... 1
- Match List - I with List - II.List - I (Biological Molecules): (a) Glycogen (b) Globulin (c) Steroids (d) ThrombinList - II (Biological functions): (i) Hormone (ii) Biocatalyst (iii) Antibody (iv) Storage productChoose the correct answer from the opt… Answer: 1. (a) - (iv), (b) - (iii), (c) - (i), (d) - (ii) Key idea: Match molecule and function. (a) Glycogen: storage product, (iv). (b) Gl... 1
- Which of the following is a correct statement ? Answer: 2. Cyanobacteria are a group of autotrophic organisms classified under Kingdom Monera. Key idea: Cyanobacteria are autotrophic and b... 1
- Given below are two statements :Statement I :In a scrubber the exhaust from the thermal plant is passed through the electric wires to charge the dust particles.Statement II :Particulate matter (PM 2.5) can not be removed by scrubber but can be remove… Answer: 1. Statement I is incorrect but Statement II is correct Key idea: Electric charging of dust belongs to the electrostatic precipitato... 1
- The recombination frequency between the genes a & c is 5%, b & c is 15%, b & d is 9%, a & b is 20%, c & d is 24% and a & d is 29%. What will be the sequence of these genes on a linear chromosome ? Answer: 1. a, c, b, d Key idea: Higher recombination frequency means a greater distance between genes. The farthest pair sits at the ends. T... 1
- Ten E.coli cells with ^15N - dsDNA are incubated in medium containing ^14N nucleotide. After 60 minutes, how many E.coli cells will have DNA totally free from ^15N ? Answer: 4. 60 cells Key idea: DNA replication is semi-conservative, and the question assumes the usual E. coli doubling time of 20 minutes.... 1
- If a colour blind female marries a man whose mother was also colour blind, what are the chances of her progeny having colour blindness ? Answer: 1. 100% Key idea: Colour blindness is X-linked recessive. The female is colour blind: X^cX^c . The man's mother was colour blind, so... 1
- Breeding crops with higher levels of vitamins and minerals or higher proteins and healthier fats is called : Answer: 4. Bio-fortification Key idea: Breeding crops for higher vitamins, minerals, proteins and healthier fats is called biofortification.... 1
- Identify the microorganism which is responsible for the production of an immunosuppressive molecule cyclosporin A : Answer: 2. Trichoderma polysporum Key idea: Cyclosporin A, an immunosuppressant used in organ transplants, is produced by the fungus Trichod... 1
- A dehydration reaction links two glucose molecules to produce maltose. If the formula for glucose is C_6H_12O_6 then what is the formula for maltose ? Answer: 4. C₁₂H₂₂O₁₁ Key idea: A dehydration reaction removes one water molecule when two units join. 2 glucose = mathrmC₁₂H₂₄O₁₂ . Subtract... 1
- Select the incorrect statement with reference to mitosis : Answer: 3. Spindle fibres attach to centromere of chromosomes. Key idea: Spindle fibres attach to the kinetochores, which are protein discs... 1
- Given below are two statements :Statement I :Mycoplasma can pass through less than 1 micron filter size.Statement II :Mycoplasma are bacteria with cell wallIn the light of the above statements, choose the most appropriate answer from the options give… Answer: 4. Statement I is correct but Statement II is incorrect Key idea: Mycoplasma are the smallest bacteria and have no cell wall. Statem... 1
- In the taxonomic categories which hierarchial arrangement in ascending order is correct in case of animals ? Answer: 2. Kingdom, Phylum, Class, Order, Family, Genus, Species Key idea: The standard hierarchy is Kingdom, Phylum, Class, Order, Family,... 1
- In-situ conservation refers to : Answer: 2. Protect and conserve the whole ecosystem Key idea: In-situ conservation protects species in their natural habitat, so the whole e... 1
- If '8' Drosophila in a laboratory population of '80' died during a week, the death rate in the population is ______ individuals per Drosophila per week. Answer: 2. 0.1 Key idea: Death rate per individual = deaths ÷ population size. death rate = 8/80 = 0.1 individuals per Drosophila per week. 1
- Detritivores breakdown detritus into smaller particles. This process is called : Answer: 3. Fragmentation Key idea: Detritivores such as earthworms break detritus into smaller particles. This step is fragmentation. It is... 1
- If the length of a DNA molecule is 1.1 metres, what will be the approximate number of base pairs ? Answer: 2. 3.3×10⁹ bp Key idea: Distance between two base pairs is 0.34\ nm = 0.34×10⁻⁹ m. N = dfrac1.10.34×10⁻⁹ ≈ 3.2×10⁹ ≈ 3.3×10⁹ bp, whi... 1
- In an E.coli strain i gene gets mutated and its product can not bind the inducer molecule. If growth medium is provided with lactose, what will be the outcome ? Answer: 4. z, y, a genes will not be translated Key idea: If the repressor (product of the i gene) cannot bind the inducer, it stays bound t... 1
- Read the following statements on lipids and find out correct set of statements :(a) Lecithin found in the plasma membrane is a glycolipid(b) Saturated fatty acids possess one or more c=c bonds(c) Gingely oil has lower melting point, hence remains as… Answer: 4. (c), (d) and (e) only (a) Lecithin is a phospholipid, not a glycolipid: false. (b) Saturated fatty acids have no double bonds: fa... 1
- Regarding Meiosis, which of the statements is incorrect ? Answer: 3. DNA replication occurs in S phase of Meiosis-II Key idea: DNA replicates only once in meiosis, in the S phase before meiosis I. M... 1
- Addition of more solutes in a given solution will : Answer: 3. lower its water potential Water potential of pure water is highest (zero). Adding solute lowers the free energy of water, so solu... 1
- Match List - I with List - II.List - I: (a) Metacentric chromosome (b) Acrocentric chromosome (c) Sub-metacentric chromosome (d) Telocentric chromosomeList - II: (i) Centromere situated close to the end forming one extremely short and one very long a… Answer: 2. (a) - (iii), (b) - (i), (c) - (iv), (d) - (ii) Metacentric: centromere in the middle, two equal arms, (iii). Acrocentric: centrom... 1
- Which of the following statements with respect to Endoplasmic Reticulum is incorrect ? Answer: 4. In prokaryotes only RER are present Key idea: Prokaryotes have no endoplasmic reticulum at all, because they lack membrane-bound... 1