#neet
- All of the following are included in 'Ex-situ conservation' except Answer: 3. Sacred groves Key idea: Ex-situ conservation means protecting species outside their natural habitat. In-situ means within the nat... 1
- Match the items given in Column I with those in Column II and select the correct option given below :Column I | Column IIa. Eutrophication | i. UV-B radiationb. Sanitary landfill | ii. Deforestationc. Snow blindness | iii. Nutrient enrichmentd. Jhum… Answer: 2. a-iii b-iv c-i d-ii Key idea: Match each term with its meaning. Eutrophication: nutrient enrichment of water (iii). Sanitary land... 1
- In a growing population of a country, Answer: 1. pre-reproductive individuals are more than the reproductive individuals. Key idea: The age pyramid shape shows population growth.... 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
- 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 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
- World Ozone Day is celebrated on Answer: 2. 16 ^th September World Ozone Day marks the signing of the Montreal Protocol on 16 September 1987. 5 June is World Environment Day... 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
- 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
- Which among the following is *not* a prokaryote ? Answer: 1. *Saccharomyces* Saccharomyces is yeast, a unicellular fungus, so it is a eukaryote. Nostoc and Oscillatoria are cyanobacteria and... 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
- 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
- Select the *wrong* statement : Answer: 2. Pseudopodia are locomotory and feeding structures in Sporozoans. Sporozoans (e.g. Plasmodium) have no locomotory organs, so the s... 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: 4. Francois Jacob and Jacques Monod – *Lac* operon Jacob and Monod proposed the lac operon model of gene regulation in E. coli. Jeff... 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
- 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
- Which of the following is commonly used as a vector for introducing a DNA fragment in human lymphocytes ? Answer: 1. Retrovirus To put a gene into animal cells such as human lymphocytes, disarmed retroviruses are used as vectors. Retroviruses inf... 1
- The correct order of steps in Polymerase Chain Reaction (PCR) is Answer: 4. Denaturation, Annealing, Extension PCR is a cycle of three steps in a fixed order: denaturation, annealing, extension. Heat (abou... 1
- In India, the organisation responsible for assessing the safety of introducing genetically modified organisms for public use is Answer: 4. Genetic Engineering Appraisal Committee (GEAC) In India GEAC (Genetic Engineering Appraisal Committee) decides on the safety of G... 1