Questions

• Cactus spines are also known as modified bud scales, which are also called modified leaves.

• Cactus spines occur in clusters in the axil of leaves.

Deoxyribonucleic acid (DNA) is a nucleic acid polymer composed of monomers called nucleotides. Nucleotides are composed of three components: (1) a pentose sugar; (2) a nitrogenous base; and (3) one to three phosphate groups.

Phoebus Levene, a Russian biochemist was the first to discover the nucleotide and the first to correctly identify the way nucleic acid molecules, DNA.

Atomic weight=number of neutrons+number of protons

Public relations includes promotional activities that work to create a strong public image of the company. Public relations activities include helping the public to understand the company and its products. Public relations if done right can reach a large audience without the expensive cost of traditional advertising and marketing.

Parabola, because when the coin is dropped at a particular point, it has the same velocity as the running train. So by Newton's first law, it continues its motion horizontally with that velocity. But then, it is also pulled down by earth's gravity continuously. In this situation its horizontal motion gives way to the parabolic motion until it reaches the ground.