Which of the following is a fossil fuel?

The process of separating petroleum into useful fractions is called:

The main constituent of natural gas is:

The purest form of carbon is:

Which form of coal has the highest carbon content?

Petroleum is formed from:

Coal is mainly used for:

The process of coal formation is called:

Which fuel is called ‘black gold’?

Diesel is obtained from:

Kerosene is used mainly for:

The product used to make roads is:

Which gas is supplied in CNG cylinders?

Which of the following is NOT a fossil fuel?

Petrol is mainly used in:

LPG mainly contains:

A disadvantage of fossil fuels is:

Which is an exhausted natural resource?

A product obtained from coal used in steel manufacturing is:

Coal tar is used to make:

Paraffin wax is used in making:

Natural gas is a cleaner fuel because:

Petrol and diesel belong to which group?

Which form of coal is soft and brownish?

CNG stands for:

The petroleum fraction used as fuel in aircraft is:

The main disadvantage of using CNG vehicles is:

Fossil fuels were formed over:

The alternative energy resource to reduce fossil fuel use is:

Sound is produced due to:

The number of vibrations per second is called:

The SI unit of frequency is:

The maximum displacement of a vibrating body from its mean position is:

Sound cannot travel through:

The speed of sound is highest in:

High frequency sound is called:

The human ear can hear sounds between:

The time taken to complete one vibration is called:

Loudness of sound is measured in:

Sound travels fastest in which medium?

A sound with frequency below 20 Hz is called:

Which part of the ear collects sound?

The eardrum vibrates when:

Higher amplitude means:

High frequency sound has:

Sound is a:

The sound produced by a mosquito has:

When a bell is struck harder, its sound becomes:

Sound waves travel by:

Which of the following will result in noise?

Reflection of sound is called:

Echo can be heard only if the reflecting surface is at least:

Sound can travel through:

Noise pollution can cause:

The unit of loudness is:

Soft materials like carpets reduce noise by:

The device used to measure frequency is:

Sound produced by a drum has:

Which part of the ear sends electrical signals to the brain?

Adolescence begins around the age of:

The period of transition from childhood to adulthood is called:

The onset of puberty in girls generally occurs between:

The onset of puberty in boys generally occurs between:

The gland called the “master gland” is:

Which hormone is responsible for changes in boys during puberty?

Which hormone is responsible for changes in girls during puberty?

The Adam’s apple is more prominent in:

The larynx in boys grows larger during puberty causing:

The period when the body becomes capable of reproduction is called:

The changes that occur during adolescence are controlled by:

Growth of moustache and beard occurs due to:

Menstruation in girls usually begins at:

Rapid physical changes during adolescence are known as:

Which vitamin is essential for strong bones during adolescence?

Iron-rich foods are especially important for:

Which of the following is a secondary sexual characteristic?

Reproductive age in women lasts from approximately:

Night blindness can occur due to lack of:

Which of these changes occurs in both boys and girls during puberty?

The hormone that regulates metabolism is:

The menstrual cycle in girls occurs roughly every:

Voice cracks during puberty because:

Sweating increases during adolescence due to:

Overeating junk food during adolescence may cause:

Reproductive health means:

A balanced diet includes:

Personal hygiene is important during adolescence to avoid:

Emotional changes during adolescence occur due to:

Which of the followings is NOT a healthy habit for adolescents?

The process by which living organisms produce new individuals is called:

Animals that give birth to young ones are called:

Animals that lay eggs are called:

The union of male and female gametes is called:

The male reproductive cell is called:

The female reproductive cell is called:

The process of fertilization in humans is:

Which of the following shows external fertilization?

The cell formed after fertilization is called:

The zygote grows and develops into a: