If electrodes were immersed in water, and a current is passed

(a) Oxygen bubbles formed at the positive terminal
(b) Hydrogen bubbles formed at the positive terminal
(c) Hydrogen bubbles formed at the negative terminal
(d) A & C

 Match [electroplating – purpose]

I. Tin a. Resists scratches
II. Chromium b. Protection from getting spoilt
III. Gold c. Appearance
IV. Zinc d. Protection from corrosion

I II III IV
(a) b a c d
(b) a b c d
(c) a b d c
(d) b a d c

 Fertilization very common in aquatic animals is

(a) External fertilization
(b) Internal fertilization
(c) In vitro fertilization
(d) B & C

loning is the production of

I. An exact copy of a cell II. Any other living part III. A complete organism
(a) I & III only
(b) II & III only
(c) III only
(d) I, II & III

 Which is INCORRECT?

1. The basic components of a cell are cell membrane, cytoplasm and nucleus
2.Chromosomes help in inheritance or transfer of characters from the parents to the offspring
3. Animal cells differ from Plant cells in having an additional layer around the cell membrane termed cell wall
(a) 1 Only
(b) 3 Only
(c) 1 & 2
(d) 1, 2 & 3

A: For fires involving electrical equipment and inflammable materials like petrol, carbon dioxide is the best extinguisher

R: carbon dioxide is lighter than oxygen and the contact between the fuel and oxygen is cut off
(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

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