Which is CORRECT?

1. Viruses reproduce only inside the cells of the host organism
2.Common ailments like cold, influenza (flu) and most coughs are caused by viruses
3. Serious diseases like polio and chicken pox are also caused by viruses
(a) 1 Only
(b) 3 Only
(c) 1 & 2
(d) 1, 2 & 3

 

Which is INCORRECT?

1. Rayon or artificial silk is obtained from a natural source, wood pulp
2.Nylon is prepared from coal, water and air and it was the first fully synthetic fibre
3. Polyester is another synthetic fibre and fabric made from this fibre does get wrinkled easily
4. Cotton is a polymer made of many repeating units called cellulose
(a) 1 Only
(b) 3 Only
(c) 1 & 2 only
(d) 4 Only

Which of the following statements are CORRECT?

1. Antibiotics are being produced only from bacteria
2.Antibiotics are not effective against cold and flu as these are caused by viruses
3. Antibiotics are even mixed with the feed of livestock and poultry to check microbial infection in animals
(a) 1 Only
(b) 2 & 3 Only
(c) 1 & 2 only
(d) 1, 2 & 3

Diseases can be prevented by vaccination

(a) Cholera & Tuberculosis
(b) Smallpox and Hepatitis
(c) Small pox only
(d) Both A & B

Communicable diseases

1. Spread from an infected person to a healthy person through air, water, food or physical contact
2.Cholera, common cold, chicken pox and tuberculosis are examples of Communicable diseases
3. Some insects and animals which act as carriers of disease causing microbes
4. Female Aedes mosquito acts as carrier of malaria
Which is NOT CORRECT?
(a) 4 Only
(b) 2 Only
(c) 1 & 2 only
(d) 1, 2 & 3 only

Which is NOT MATCHED? [Disease – Microorganism – Transmission]

(a) Polio – Virus – Air
(b) Tuberculosis – Bacteria – Water
(c) Cholera – Bacteria – Food
(d) Malaria – Protozoa – Mosquito

Match

1. Preservation by Common Salt a. Jellies and squashes
II. Preservation by Sugar b. Raw mangoes
III. Preservation by Oil and Vinegar c. Vegetables & fruits
IV. Common preservatives d. Sodium benzoate
e. Sodium metabisulphite
I II III IV
(a) b a c d & e
(b) a b c d only
(c) a b c d & e
(d) b a c d only
 

Nitrogen is one of the essential constituents of all living organisms as part of

(a) Proteins & Chlorophyll
(b) Nucleic acids and vitamins

(c) Both A & B
(d) Proteins, Chlorophyll and Nucleic acids only

A: PVC, a thermosetting plastic, used for making electrical switches and handles of various Utensils

R: Thermosetting plastics when moulded once cannot be softened by heating
(a) A & R are CORRECT; R is CORRECT explanation for A
(b) A & R are CORRECT; But, R is not-CORRECT explanation for A
(c) A is CORRECT; But not R
(d) R is CORRECT; But not A

A: To prevent the contact of phosphorus with atmospheric oxygen, it is stored in water

R: phosphorus is a very reactive Metal
(a) A & R are CORRECT; R is CORRECT explanation for A
(b) A & R are CORRECT; But, R is not-CORRECT explanation for A
(c) A is CORRECT; But not R
(d) R is CORRECT; But not A

Uses of Nonmetals

1. Some non – metals essential for our life which all living beings inhale during breathing
2.Some non – metals Used in fertilizers to enhance the growth of plants
3. Some non – metals used in water purification process
4. Some non – metals used as an antiseptic
Which are CORRECT?
(a) 1 & 2 Only
(b) 2 & 3 Only
(c) 3 & 4 only
(d) 1, 2, 3 & 4