The answer is that the criteria of classification change with the improved understanding of organisms around us. During the time of Aristotle, not much was known about the living organisms. So, he classified them as he observed. Plants were classified into herbs, shrubs and trees; very much like what’s taught to a second grade student. Animals as Enaima and Anaima based on the presence or absence of RBCs. After him, Carolus Linnaeus tried his hand over classification. He came up with the 2 kingdom classification: Plants and Animals. He considered only a set of morphological and physiological criteria to decide the kingdom to which an organism belongs. It includes presence of cell wall, mode of nutrition, contractile vacuole, locomotion and others. Based on these criteria, he included widely differing organisms into a single kingdom, for example, fungi, bacteria, algae, and higher plants were included into plant kingdom just because they have cell wall as a common aspect. Then came, Ernst Haeckel, who came with a third kingdom of Protista to include unicellular organisms. Copeland gave a 4 kingdom classification segregating unicellular organisms into 2 separate kingdoms based on their nuclear structure. R.H. Whittaker came next introducing the most accepted 5 kingdom classification system. You should understand one thing that man’s knowledge of classifying organisms improved with the improving technologies available to him, which he exploited to very effective extent. Carl Woese gave the 6 kingdom classification and 3 domain system based on the 16S rRNA sequence.
Our understanding of organisms around us is improving day by day and the system of classification will also change further in pace with the improvement in technology.
I hope this helps! :D]
~ Kana ^^
Polysaccharides at made up of 2 or more monosaccharides bonded together
All living creatures are classified into systems and sub-systems based on their similar characteristics. They are divided from bigger groups into smaller groups based on the detail of their similarities i.e. how they look, move, reproduce and how they relate to each other. A practical way of understanding the classification of living organisms is that organisms are linked to other similar organisms via family trees. The classification of all living creatures includes at least four levels: order, families, genus and species.
Thermal energy transfer. Ex. Hot to Cold
Answer:
By the numbers, humans produce a lot of food—enough to provide every person on Earth 2,750 calories per day, exceeding almost all dietary recommendations.
There’s one glaring problem, however: Humans aren’t producing enough of the right food.
When researchers at the University of Guelph in Canada broke those calories down into different food groups, they found a shortage in production of the most important foods. In the long run, with the global population expected to balloon to about 10 billion people by mid-century, this could cause some serious problems.
Explanation:
