Botany
- Identify the wrong statement in context of heartwood : Answer: 2. It conducts water and minerals efficiently Key idea: Heartwood is the old, central secondary xylem that has stopped conducting. I... 1
- Which of the following facilitates opening of stomatal aperture ? Answer: 2. Radial orientation of cellulose microfibrils in the cell wall of guard cells Key idea: A stoma opens when guard cells become turg... 1
- The central dogma of molecular genetics states that the genetic information flows from Answer: 2. DNA → RNA → Proteins Key idea: the central dogma: DNA is transcribed to mRNA, which is translated to protein. Information flows D... 1
- Which of the following is the least likely to be involved in stabilizing the three-dimensional folding of most proteins? Answer: 3. Ester bonds Protein 3D structure is stabilised by hydrogen bonds, hydrophobic interactions, ionic (electrostatic) interactions an... 1
- When cell has stalled DNA replication fork, which checkpoint should be predominantly activated? Answer: 1. G ₂ /M A stalled replication fork means DNA is not fully replicated. The cell must delay entry into mitosis until replication and... 1
- Which of the following describes the given graph correctly? Answer: 1. Exothermic reaction with energy A in presence of enzyme and B in absence of enzyme The graph shows energy released, and the arrow... 1
- Oxidative phosphorylation is Answer: 3. formation of ATP by energy released from electrons removed during substrate oxidation Oxidative phosphorylation is the formation... 1
- Interspecific hybridization is the mating of Answer: 1. two different related species In interspecific hybridisation, male and female animals of two different related species are mated... 1
- Match Column—I with Column—II and select the correct option using the codes given below :Column—I: a. Citric acid; b. Cyclosporin A; c. Statins; d. Butyric acidColumn—II: (i) Trichoderma; (ii) Clostridium; (iii) Aspergillus; (iv) MonascusCodes :a b c… Answer: 1. (iii) (i) (iv) (ii) Citric acid: Aspergillus niger (iii). Cyclosporin A (immunosuppressant): Trichoderma polysporum (i). Statins... 1
- Study the four statements (A-D) given below and select the two correct ones out of them :A. Definition of biological species was given by Ernst Mayr.B. Photoperiod does not affect reproduction in plants.C. Binomial nomenclature system was given by R.… Answer: 2. A and D A: Ernst Mayr gave the biological species concept. True. B: Photoperiod affects flowering and reproduction in plants. Fal... 1
- Biochemical Oxygen Demand (BOD) may not be a good index for pollution for water bodies receiving effluents from Answer: 2. petroleum industry BOD measures the oxygen needed by microbes to break down organic matter, so it is a good index for organic was... 1
- A lake which is rich in organic waste may result in Answer: 3. mortality of fish due to lack of oxygen A lake with a lot of organic waste has a high microbial decomposition. The microbes use u... 1
- Which of the following National Parks is home to the famous musk deer or hangul? Answer: 3. Dachigam National Park, Jammu & Kashmir The Kashmir stag, called hangul, lives in Dachigam National Park in Jammu and Kashmir. Ke... 1
- The highest DDT concentration in aquatic food chain shall occur in Answer: 1. seagull DDT is not broken down and builds up at each higher trophic level (biomagnification). The seagull is the top consumer her... 1
- The principle of competitive exclusion was stated by Answer: 1. G. F. Gause The competitive exclusion principle was stated by G. F. Gause. It says two closely related species competing for the... 1
- A molecule that can act as a genetic material must fulfill the traits given below, except Answer: 2. it should be unstable structurally and chemically A genetic material must: replicate itself, express itself (as Mendelian charact... 1
- If a colour-blind man marries a woman who is homozygous for normal colour vision, the probability of their son being colour-blind is Answer: 4. 0 Colour blindness is X-linked recessive. Let the normal allele be X and the defective allele X^c. Father: X^cY. Mother (homozygo... 1
- DNA-dependent RNA polymerase catalyzes transcription on one strand of the DNA which is called the Answer: 4. template strand In transcription, RNA polymerase reads one DNA strand, which acts as the template strand (it has 3' to 5' polarit... 1
- Match the stages of meiosis in Column—I to their characteristic features in Column—II and select the correct option using the codes given below :Column—I: a. Pachytene; b. Metaphase I; c. Diakinesis; d. ZygoteneColumn—II: (i) Pairing of homologous ch… Answer: 4. (iii) (iv) (ii) (i) Each stage of meiotic prophase I has one signature event. Pachytene: crossing-over between non-sister chromat... 1
- Select the wrong statement. Answer: 4. The walls of diatoms are easily destructible. Diatom cell walls are made of silica and are indestructible, so statement 4 is wron... 1
- Which one of the following is wrong for fungi? Answer: 1. All fungi possess a purely cellulosic cell wall. Fungal cell walls are made of chitin and other polysaccharides, not purely cellu... 1
- Methanogens belong to Answer: 1. Archaebacteria Methanogens produce methane under anaerobic conditions (for example in the gut of ruminants and in biogas plants)... 1
- Conifers are adapted to tolerate extreme environmental conditions because of Answer: 2. thick cuticle Conifers grow in cold, dry conditions. A thick cuticle and sunken stomata, with needle-like leaves, reduce water lo... 1
- Which one of the following statements is wrong ? Answer: 1. Algin is obtained from red algae, and carrageenan from brown algae. The statement is reversed. Algin comes from brown algae and c... 1