Answer:
Single-cell organisms
Explanation:
In 1735, Linnaeus introduced a classification system with only two kingdoms: animals and plants. Linnaeus published this system for naming, ranking, and classifying organisms in the book "Systema Naturae". In the epoch that Linnaeus created this system, single-cell organisms such as bacteria and protists were almost unknown. In 1866, E. Haeckel added a category including both bacteria and protozoa, thereby adding a category formed by single-cell organisms (different from animals and plants). During the 1900-1920 period, bacteria were classified as a separated kingdom named 'prokaryotes'. The current three-domain classification system was introduced by C. Woese in 1990. In this system, all forms of life are divided into three different domains: archaea, bacteria, and eukaryote domains (this last composed of protists, fungi, plants and animals).
2) Cross-fertilization makes for more variation in the traits of plants, giving them immunities and resistances to weather, pests, and disease.
Correct answer: A). The enzyme influences the speed of change from substrate to product
The enzymes are the biological catalyst that speed up the rate of chemical reactions by decreasing the activation energy of the reaction pathway.
They increase the speed of change of substrate to the product and it remains unchanged in the reaction. Hence, it can be used again and again.
Enzymes are highly specific in nature, only a specific substrate binds to the enzyme's active site. Hence, a particular enzyme is required to catalyze a reaction.