A good reason for why tobacco smoke is considered a carcinogen is because it causes mutations leading to cancer.
The correct answer is: A. How does changing the amount of water affect the growth of corn?
While options B, C & D are not impossible to test, option A is the only question that can be tested using quantitative methods, such as statistical analysis. The question in option A states: "How does changing the amount of water affect the growth of corn?". This question is easily testable using scientific investigation, because controlled or measured amounts of water can be added to corn, and the consequent growth rate of corn can be easily measured and recorded. However, the questions in options B, C & D cannot be precisely measured using quantitative tools, since they aim to measure qualitative (subjective) factors, such as: ethics, happiness and disappointment.
The believe that the best answer among the choices provided by the question is the E. All contain histones.
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Taxonomy- the classification of something, especially organisms.
Classify- arrange (a group of people or things) in classes or categories according to shared qualities or characteristics.
Binomial nomenclature- the scientific way to name living things with a two part generic (genus) and specific (species) name.
Kingdom- a country, state, or territory ruled by a king or queen.
Species- a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding. The species is the principal natural taxonomic unit, ranking below a genus and denoted by a Latin binomial, e.g. Homo sapiens.
Prokaryote- a microscopic single-celled organism which has neither a distinct nucleus with a membrane nor other specialized organelles, including the bacteria and cyanobacteria.
Eukaryote- an organism consisting of a cell or cells in which the genetic material is DNA in the form of chromosomes contained within a distinct nucleus. Eukaryotes include all living organisms other than the eubacteria and archaea.
Heterotroph- an organism deriving its nutritional requirements from complex organic substances.
Autotroph- an organism that is able to form nutritional organic substances from simple inorganic substances such as carbon dioxide.
Unicellular- having or consisting of a single cell.
Multicellular- composed of several or many cells.
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66% of new HIV infections occur in sub-saharan Africa.