Onion is a modified form of

• leaf
• stem
• root
• None of these
Correct Option: B  [ stem ]

Remark:

Dehydration in human body is caused due to the loss of

• salts
• water
• hormones
• vitamins
Correct Option: B  [ water ]

Remark:

The phenomenon of radioactivity was discovered by:

• Marie Curie
• Pierre Curie
• Henri Becquerel
• J J Thomson
Correct Option: C  [ Henri Becquerel ]

Remark:

To an astronaut in space, the sky appears to be:

• Red
• White
• Dark
• Blue
Correct Option: C  [ Dark ]

Remark:

Thyroid gland is located

• near the heart
• at the base of the brain
• below the liver
• in the neck region
Correct Option: D  [ in the neck region ]

Remark:

The location of where an organism lives would be best described as its:

• niche
• habitat
• range
• biome
Correct Option: B  [ habitat ]

Remark:

Sound-waves from a loud speaker is caused by:

• frequency
• vibrations
• pitch
• amplitude
Correct Option: B  [ vibrations ]

Remark:

Which of the following statements is correct ?

• Protons are negatively charged and are present in the nucleus
• Electrons are positively charged and are present in the nucleus
• Electrons are negatively charged and are present in the orbits
• The entire mass of atom is distributed in the orbits
Correct Option: C  [ Electrons are negatively charged and are present in the orbits ]

Remark:

The speed of light will be minimum while passing through :

• Glass
• Vacuum
• Air
• Water
Correct Option: A  [ Glass ]

Remark:

Cause of global warming is:

• Excessive use of organic manure
• Increase in the amount of CO₂ in the atmosphere
• Increase in the amount of atmospheric nitrogen
• Excessive use of fertilizer.
Correct Option: B  [ Increase in the amount of CO₂ in the atmosphere ]

Remark: