Regular intake of fresh fruits and vegetables is recommended in the diet since they are a good source of antioxidants. How do antioxidants help a person maintain health and promote longevity?

Options

(a)

They activate the enzyme necessary for vitamin synthesis in the body and help prevent vitamin deficiency.

(b)

They prevent excessive oxidation of carbohydrates, fats and protein in the body and help avoid unnecessary wastage of energy.

(c)

They neutralize the free radical produced in the body during metabolism.

(d)

They activate certain genes in the cells of the body and help delay the ageing process.

Answer

(C)

Science and Technology › Biology,Human Physiology

2011

A married couple adopted a male child. A few years later, twin boys were born to them. The blood group of the couple is AB positive and O negative. The blood group of the three sons is A positive, B positive, and O positive. The blood group of the adopted son is?

Options

(a)

O positive

(b)

A positive

(c)

B positive

(d)

Cannot be determined on the basis of the given data

Answer

(A)

Chemistry

Science and Technology › Chemistry

2011

Aspartame is an artificial sweetener sold in the market. It consists of amino acids and provides calories like other amino acids. Yet, it is used as a low-calorie sweetening agent in food items. What is the basis of this use?

Options

(a)

Aspartame is as sweet as table sugar, but unlike table sugar, it is not readily oxidized in the human body due to lack of requisite enzymes.

(b)

When aspartame is used in food processing, the sweet taste remains, but it becomes resistant to oxidation.

(c)

Aspartame is as sweet as sugar, but after ingestion into the body, it is converted into metabolites that yield no calories.

(d)

Aspartame is several times sweeter than table sugar, hence food items made with small quantities of aspartame yield fewer calories on oxidation.

Answer

(D)

Emerging TechXCommunication

Science and Technology › Emerging TechXCommunication

2011

What is the difference between Bluetooth and Wi-Fi devices?

Options

(a)

Bluetooth uses 2.4 GHz radio frequency band, whereas Wi-Fi can use 2.4 GHz or 5 GHz frequency band.

(b)

Bluetooth is used for wireless local area networks (WLAN) only, whereas Wi-Fi is used for wireless wide area networks (WWAN) only.

(c)

When information is transmitted between two devices using Bluetooth technology, the devices have to be in the line of sight of each other, but when Wi-Fi technology is used the devices need not be in the line of sight of each other.

(d)

The statements (a) and (b) given above are correct in this context.

Answer

(A)

Science and Technology › Emerging TechXCommunication

2011

What is a “Virtual Private Network”?

Options

(a)

It is a private computer network of an organization where the remote users can transmit encrypted information through the server of the organization.

(b)

It is a computer network across a public internet that provides users access to their organization’s network while maintaining the security of the information transmitted.

(c)

It is a computer network in which users can access a shared pool of computing resources through a service provider.

(d)

None of the statements (a), (b) and (c) given above is the correct description of virtual private networks.

Answer

(B)

Emerging TechXIT

Science and Technology › Emerging TechXIT

2011

A new optical disc format known as the Blu-ray disc is becoming popular. In what way is it different from the traditional DVD?
1. DVD supports standard definition video while Blu-ray disc supports high-definition video.
2. Compared to a DVD, the Blu-ray disc format has several times more storage capacity.
3. Thickness of Blu-ray discs is 2.4 mm while that of DVD is 1.2 mm.

Options

(a)

1 only

(b)

1 and 2 only

(c)

2 and 3 only

(d)

1, 2 and 3

Answer

(B)

Genetics,Biotechnology

Science and Technology › Genetics,Biotechnology

2011

At present, scientists can determine the arrangement or relative positions of genes or DNA sequences on a chromosome. How does this knowledge benefit us? 1. It is possible to know the pedigree of livestock. 2. It is possible to understand the causes of all human diseases. 3. It is possible to develop disease-resistant animal breeds.

Options

(a)

1 and 2 only

(b)

2 only

(c)

1 and 3 only

(d)

1, 2 and 3

Answer

(C)

Nuclear Energy Technology

Science and Technology › Nuclear Energy Technology

2011

The function of heavy water in a nuclear reactor is to?

Options

(a)

Slow down the speed of neutrons.

(b)

Increase the speed of neutrons.

(c)

Cooldown the reactor.

(d)

Stop the nuclear reaction.

Answer

(A)

PhysicsXGeneral

Science and Technology › PhysicsXGeneral

2011

An artificial satellite orbiting around the Earth does not fall down. This is so because the attraction of Earth

Options

(a)

does not exist at such a distance.

(b)

is neutralized by the attraction of the moon.

(c)

provides the necessary speed for its steady motion.

(d)

provides the necessary acceleration for its motion.

Answer

(D)

Science and Technology › PhysicsXGeneral

2011

The surface of a lake is frozen in severe winter, but the water at its bottom is still liquid. What is the reason?

Options

(a)

Ice is a bad conductor of heat.

(b)

Since the surface of the lake is at the same temperature as the air, no heat is lost.

(c)

The density of water is maximum at 4°c.

(d)

None of the statements (a), (b) and (c) given is correct.

Answer

(C)