NOTE—Q.no.1 to 30 carry two marks each.Q.no.31 to 35 carry three marks each.
Q.1 Differentiate between chloroplasts and chromoplasts.
Q.2 Why were the cells remained undiscovered for a long time?
Q.3 Name the unit used to express cell size. Express its value in metres.
Q.4 What is the function of albumen and yolk in an egg?
Q.5 What is the composition and function of cytoplasm?
Q.6 Describe the structure of nucleus.
Q.7 What is the importance of cilia and flagella ?
Q.8 Describe the various levels of organization.
Q.9 Why do plant cells have cell wall?
Q.10 Classify the living organisms on the basis of the cell number.
Q.11 What advantage does amoeba derive by changing shape?
Q.12 A hen’s egg can be seen easily. Is it a cell or a group of cells? Give reason.
Q.13 Are the cells in an elephant larger than the cells in a rat? Justify your answer.
Q.14 Why do vaccum packed chips not get spoiled?
Q.15 How does boiling of milk prevent its spoilage?
Q.16 A child is suffering from cholera. Answer the following------
(a) Name the causative agent and mode of transmission for the disease.
(b) State any two preventive measures against the disease.
Q.17 What are toxins? How do they affect our body?
Q.18 Why is yeast used in baking industry?
Q.19 Why are certain microbes commonly called biological nitrogen fixers ?
Q.20 What are the different modes of transmission of communicable diseases?
Q.21 How are microorganisms useful in fuel production?
Q.22 “Milk tastes sweet while curd tastes sour”. Give a suitable reason to justify this statement.
Q.23 What was the reason for Irish Famine in 1740-41 ?
Q.24 What is food poisoning? What are its symptoms? Name a bacteria and virus that cause this disease.
Q.25 How does the drying method help to preserve the food items?
Q.26 Why is salt used in the preservation of meat and fish?
Q.27 How is canning of food done?
Q.28 Name two acids added in carbonated beverages. Why are these acids used?
Q.29 Write two importance of food preservation.
Q.30 How do bacteria cause damage to teeth?
Q.31 Name two factors that affect the shape of the cell. Explain by giving an example.
Q.32 Define the following terms --- (i) organelles (ii) cell membrane (iii) cytoplasm
Q.33 A child suffering from chicken pox was taken to a doctor. The doctor told the parents that they should have got their child vaccinated earlier. Answer the following-
(i) How vaccination would have helped the child to develop immunity against the disease?
(ii) Name two viral diseases for which vaccinations are available for children other than chicken pox.
(iii) Name two methods used for administering vaccines .
Q.34 Define Rancidity , Food Preservation and Bioaugmentation.
Q.35 What is pasteurization? Why is it done? Why is pasteurized milk stored under refrigerator?