Botany
- Which of the following is a secondary pollutant ? Answer: 4. O ₃ A secondary pollutant is formed in the air by reactions of primary pollutants; ozone is formed from NO _x and hydrocarbons in... 1
- What type of ecological pyramid would be obtained with the following data ?Secondary consumer : 120 gPrimary consumer : 60 gPrimary producer : 10 g Answer: 1. Inverted pyramid of biomass A pyramid of biomass is inverted when higher trophic levels have more biomass than lower ones. Here b... 1
- Natality refers to Answer: 3. Birth rate Natality is the birth rate of a population, the number of births per unit time. Death rate is mortality; leaving the h... 1
- Niche is Answer: 4. the functional role played by the organism where it lives Niche is the functional role of an organism in its habitat, including i... 1
- Select the *correct* statement : Answer: 3. Punnett square was developed by a British scientist. The Punnett square, a tool to show gamete combinations in a cross, was devis... 1
- Which of the following pairs is *wrongly* matched ? Answer: 1. Starch synthesis in pea : Multiple alleles Starch synthesis in pea is an example of pleiotropy (one gene, many effects), not mult... 1
- Select the *correct* match : Answer: 4. Francois Jacob and Jacques Monod – *Lac* operon Jacob and Monod proposed the lac operon model of gene regulation in E. coli. Jeff... 1
- The experimental proof for semiconservative replication of DNA was first shown in a Answer: 3. Bacterium Meselson and Stahl showed semiconservative replication in 1958 using E. coli. They grew the bacteria in ¹⁵ N medium, sh... 1
- Select the *correct* match : Answer: 1. Ribozyme – Nucleic acid A ribozyme is an RNA molecule with catalytic activity, so it is a nucleic acid. Morgan is linked to linka... 1
- Stomatal movement is *not* affected by Answer: 2. O ₂ concentration Stomata respond to light, CO ₂ level, temperature and water status, but not to O ₂ concentration. Low CO ₂ and... 1
- Which of the following is *not* a product of light reaction of photosynthesis ? Answer: 3. NADH The light reaction makes ATP and NADPH and releases O ₂ from photolysis of water. NADH is a respiration carrier, not a produ... 1
- Offsets are produced by Answer: 3. Mitotic divisions Offsets are vegetative propagules formed by mitosis, so the new plants are clones. They are seen in aquatic pla... 1
- Which of the following flowers only once in its life-time ? Answer: 1. Bamboo species Some plants are monocarpic and flower only once in life; bamboo flowers once after about 50 to 100 years and then... 1
- Which of the following has proved helpful in preserving pollen as fossils ? Answer: 4. Sporopollenin Sporopollenin, the material of the pollen exine, is extremely resistant to heat, acids, alkalis and enzymes. So the... 1
- Sweet potato is a modified Answer: 3. Adventitious root Sweet potato is a root that stores food, and it arises from a non-root part, so it is an adventitious root. Tap... 1
- Plants having little or no secondary growth are Answer: 1. Grasses Secondary growth depends on a vascular cambium, which is weak or absent in monocots. Grasses are monocots with closed vas... 1
- Casparian strips occur in Answer: 4. Endodermis Casparian strips are waterproof bands of suberin on the radial and tangential walls of endodermal cells. They force wa... 1
- Secondary xylem and phloem in dicot stem are produced by Answer: 3. Vascular cambium Secondary growth in a dicot stem is by the lateral meristem called vascular cambium. Vascular cambium cuts secon... 1
- Which of the following statements is *correct* ? Answer: 1. Ovules are not enclosed by ovary wall in gymnosperms. Gymnosperms are 'naked-seeded' plants, so their ovules lie exposed and are... 1
- Pneumatophores occur in Answer: 1. Halophytes Pneumatophores are breathing roots that grow upward out of waterlogged, salty soil. They are found in mangrove plants... 1
- Zygotic meiosis is characteristic of : Answer: 3. textitChlamydomonas In zygotic meiosis the zygote divides by meiosis first, so the plant body is haploid. This is the haplontic l... 1
- Select the mismatch : Answer: 4. textitPinus - Dioecious The mismatch is Pinus - dioecious. Pinus is monoecious: male and female cones are on the same tree. Cycas... 1
- Which one of the following is related to Ex-situ conservation of threatened animals and plants ? Answer: 4. Wildlife Safari parks Ex-situ conservation protects species outside their natural habitat, for example in zoos, botanical gardens... 1
- Presence of plants arranged into well defined vertical layers depending on their height can be seen best in : Answer: 1. Tropical Rain Forest A tropical rain forest shows the best stratification, with well-defined vertical layers: emergent trees, can... 1