Chapter 16 Environmental Issues
Chapter 16 Environmental Issues Question 1. What are the various constituents of domestic sewage ? Discuss the effects of sewage discharge on a river. Solution: The domestic sewage contains every-thing that goes down the drain into the sewer of the house. The various constituents of domestic sewage are suspended solids, colloidal particles, pathogenic contaminants and […]
Chapter 15 Biodiversity and Conservation
Chapter 15 Biodiversity and Conservation Question 1. Name the three important components of biodiversity Solution: The three important components of biodiversity are genetic diversity, species diversity and ecological diversity. These components are the basic building blocks of biodiversity. These are intimately linked and may have common elements. Question 2.How do ecologists estimate the total number […]
Chapter 14 Ecosystem
Chapter 14 Ecosystem Question 1. Fill in the blanks (a) Plants are called as ___ because they fix carbon dioxide. (b) In an ecosystem dominated by trees, the pyramid (of numbers) is ___ type. (c) In aquatic ecosystem, the limiting factor for the productivity is ___ (d) Common detritivores in our ecosystem are ____ (e) […]
Chapter 13 Organisms and Populations
Chapter 13 Organisms and Populations Question 1. How is diapause different from hibernation ? Solution: Diapause is different from hibernation. The table below shows the differences between them : Question 2. If a marine fish is placed in a freshwater aquarium/will the fish be able to survive? Why or why not? Solution: If a marine […]
Chapter 12 Biotechnology and Its Applications
Chapter 12 Biotechnology and Its Applications Question 1. Crystals of Bt toxin produced by some bacteria do not kill the bacteria themselves because (a) bacteria are resistant to the toxin (b) toxin is immature (c) toxin is inactive (d) bacteria encloses toxin in a special sac. Solution: (c) Toxin is inactive: In bacteria, the toxin […]
Chapter 11 Biotechnology: Principles and Processes
Chapter 11 Biotechnology: Principles and Processes Question 1. Make a chart (with diagrammatic representation) showing a restriction enzyme, the substrate DNA on which it acts, the site at which it cuts DNA and the product it produces. Solution: Restriction enzyme – Eco RI Source – Escherichia coli RY13 Question 2. Can you list 10 recombinant […]
Chapter 10 Microbes in Human Welfare
Chapter 10 Microbes in Human Welfare Question 1. Bacteria cannot be seen with the naked eyes, but these can be seen with the help of a microscope. If you have to carry a sample from your home to your biology laboratory to demonstrate the presence of microbes under a microscope, which sample would you carry […]
Chapter 9 Strategies for Enhancement in Food Production
Chapter 9 Strategies for Enhancement in Food Production Question 1. Explain in brief the role of animal husbandry in human welfare. Solution: Animal husbandry evolves new techniques and technologies for the management of livestock like buffaloes, cows, pigs, horses, cattle, sheep, camels, goats, etc., that are useful to humans. These methods can also be applied […]
Chapter 8 Human Health and Diseases
Chapter 8 Human Health and Diseases Question 1. What are the various public health measures, which you would suggest as a safeguard against infectious diseases? Solution: Prevention and control of infectious diseases I. For water-borne diseases like typhoid, amoebiasis, etc. Practice personal and public hygienic measures. a. Personal hygienic measures Keeping the body clean Consumption […]
Chapter 7 Evolution
Chapter 7 Evolution Question 1. Explain antibiotic resistance observed in bacteria in light of Darwinian selection theory. Solution: Penicillin when discovered was used as an antibiotic against all bacteria. Soon many of these became resistant. This is because alleles of resistance which are already present in bacteria are of no importance in absence of antibiotics. […]