General Science Questions

True, the greenhouse effect is caused solely by human activities such as deforrestation, depletion of natural resources and emission of CO2 by using vehicles, refrigerators and AC's.

A pure solid and a pure liquid are definitely a single phase because they are so united, or homogeneous. This leads to a homogeneous mixture also being a single phase.

Hence, the option that cannot be considered a single phase is A. a heterogeneous mixture.

DNA stands for Deoxyribo nucleic acid. It is a nucleic acid made up of monomeric unit called Nucleotide.

A nucleotide consist of -

a) Sugar - Deoxyribose in DNA ( ribose in RNA)

b) An organic base- Adenine, cytosine, guanine.

A living community and its environment is what an ecosystem is.

Dairy products like milk, cheese and yogurt are rich source of protein as well as calcium also. 

The gas usually filled in the electric bulb is Nitrogen.

The phalanges or a phalanx are/is digital bones in the hands and feet of most vertebrates. In primates, the thumbs and big toes have two phalanges while the other digits have three phalanges. The phalanges are classed as long bones.