Macromolecule Definition and Examples

Macromolecule Definition and Examples In chemistry and biology, a  macromolecule is defined as a molecule with a very large number of atoms. Macromolecules typically have more than 100 component atoms. Macromolecules exhibit very different properties from smaller molecules, including their subunits, when applicable. In contrast, a micromolecule is a molecule which has a small size and molecular weight. The term macromolecule was coined by Nobel laureate Hermann Staudinger in the 1920s. At the time, the term polymer had a different meaning than it does today, or else it might have become the preferred word. Macromolecule Examples Most polymers are macromolecules and many biochemical molecules are macromolecules. Polymers consist of subunits, called mers, that are covalently linked to form larger structures. Proteins, DNA, RNA, and plastics are all macromolecules. Many carbohydrates and lipids are macromolecules. Carbon nanotubes are an example of a macromolecule that is not a biological material.

Answers to Questions About Hyphens in References to Age

Answers to Questions About Hyphens in References to Age Answers to Questions About Hyphens in References to Age Answers to Questions About Hyphens in References to Age By Mark Nichol The rules about references to age, and the proper use of hyphens in such references, are simple yet easily misunderstood. Here are a few explanations in response to readers’ questions about the topic. 1. Could you help me understand the correct way to write ages? For example, â€Å"My three-year-old was too young for the movie† is hyphenated, while â€Å"He is three years old† is not, or at least I dont think it is. Your examples are correct: Hyphenate â€Å"three-year-old† and similar phrases only when they serve as phrasal adjectives describing someone or something (or when, as in the case of the first example above, the someone or something of that age is implied). The simple phrase â€Å"three years old† merits no hyphenation, because it isn’t being combined to modify anything. Unfortunately, many people are confused by this distinction, so the phrase is often hyphenated incorrectly, and the frequently seen error perpetuates the confusion. 2. In your sentence â€Å"Write ‘fifty years old,’ for example, rather than ‘aged fifty years,’† the phrase should read â€Å"fifty years-old,† shouldnt it? â€Å"Fifty years old† should be styled just like that, as explained in the previous response; in reference to a fifty-year-old, hyphenate as shown whether what is fifty years old is explicit or implicit. Never hyphenate years and old while leaving the preceding number detached, and never hyphenate fifty and year without also including old in the hyphenated string of words; â€Å"fifty-year old man† refers to an old man who is fifty years, which is nonsensical. The only case in which years and old would be hyphenated is in a sentence such as â€Å"It’s a years-old tradition† a reference to a tradition that is (many) years old. 3. â€Å"When a doctor was dictating a report, he said, ‘This is an approximately 40 50 year old woman . . . .’ It’s my job as a transcriptionist to make the doctor look good; I don’t just type verbatim. So I put, ‘This is an approximately 40- to 50-year-old woman . . . .’ ‘This is a 40-50-year-old woman . . .’ looks awful and confusing, even though that is actually what the doctor said. I could also have written, ‘This is a woman who is approximately 40 or 50 years old . . . .’† Both of your solutions are elegant. If, however, you were required to transcribe verbatim and I think doing so would be necessary only in a legal context the solution would be, â€Å"This is an approximately 40-, 50-year-old woman.† The comma indicates a pause for expansion or self-correction. Want to improve your English in five minutes a day? Get a subscription and start receiving our writing tips and exercises daily! Keep learning! Browse the Punctuation category, check our popular posts, or choose a related post below:Wether, Weather, Whether50 Idioms About Arms, Hands, and FingersWoof or Weft?