1. Write the differences between cilia and flagella.
2. What are chromosomes? When they become visible? What are the functions o
chromosomes?
3. What are biological nitrogen fixers? Give examples.
4. Explain how vaccination produces immunity to the body.
5. What is food poisoning? Name the causal organisms for food poisoning.
6. Explain the methods of food preservation in detail.
7. How nitrogen dioxide is harmful for plants?
8. How carboxyhaemoglobin is formed? What are its harmful effects?
9. What is acid rain? How it is harmful?
10. Diagrammatically explain the green house effect.
11. List any 10 methods to control air pollution
'12. Make a poster showing conservation of water
13. Make a working model of solar system.
Answers
Answer:
1. Cilia are short, hair like appendages extending from the surface of a living cell. Flagella are long, threadlike appendages on the surface of a living cell. Occurs throughout the cell surface. Presence at one end or two ends or all over the surface.
Answer:
1.Cilia are short, hair like appendages extending from the surface of a living cell. Flagella are long, threadlike appendages on the surface of a living cell. Occurs throughout the cell surface. Presence at one end or two ends or all over the surface.
2.During interphase (1), chromatin is in its least condensed state and appears loosely distributed throughout the nucleus. Chromatin condensation begins during prophase (2) and chromosomes become visible. Chromosomes remain condensed throughout the various stages of mitosis (2-5).
3.Examples of this type of nitrogen-fixing bacteria include species of Azotobacter, Bacillus, Clostridium, and Klebsiella. As previously noted, these organisms must find their own source of energy, typically by oxidizing organic molecules released by other organisms or from decomposition.
4.Vaccines give you immunity to a disease without you getting sick first. They are made using killed or weakened versions of the disease-causing germ or parts of the germ (called antigens). For some vaccines, genetic engineering is used to make the antigens used in the vaccine.
5.Food poisoning is defined as an illness caused by the consumption of food or water contaminated with bacteria and/or their toxins, or with parasites, viruses, or chemicals. The most common pathogens are Norovirus, Escherichia coli, Salmonella, Clostridium perfringens, Campylobacter, and Staphylococcus aureus.
6.To extend the longevity of food used at home or in your food business, you can use refrigeration, freezing, canning, sugaring, salting, and even vacuum packing.
7.Nitrogen dioxide is toxic to plants in short-term concentrations of 120 µg/m3. It reduces plant growth. When sulphur dioxide and ozone are also present, the effects on vegetation are worse. Along with sulphur dioxide, nitrogen dioxide can cause acid rain.
8.Carboxyhemoglobin (COHb) is a stable complex of carbon monoxide that forms in red blood cells when carbon monoxide is inhaled. It is produced from hepatic metabolism of methylene chloride or as a byproduct in the process of hemoglobin degradation.
9.When acid rain falls down and flows into the rivers and ponds it affects the aquatic ecosystem. As it alters the chemical composition of the water, to a form which is actually harmful to the aquatic ecosystem to survive and causes water pollution. Acid rain also causes the corrosion of water pipes.
10.Greenhouse effect, a warming of Earth's surface and troposphere (the lowest layer of the atmosphere) caused by the presence of water vapor, carbon dioxide, ...
11.10 Best Ways to Reduce Air Pollution
1.Using public transports. ...
2.Turn off the lights when not in use. ...
3.Recycle and Reuse. ...
4.No to plastic bags. ...
5.Reduction of forest fires and smoking. ...
6.Use of fans instead of Air Conditioner. ...
7.Use filters for chimneys. ...
8.Avoid usage of crackers.
9. Avoid using of products with chemicals
10. Implement Afforestation