Biology

1. What are the three domains of life?
-Bacteria: Domain Bacteria is familiar to most people when associated with human or animal disease. However, most bacterial species do not (and cannot) cause disease. Many species even play beneficial roles by producing antibiotics and food. The soil teems with free-living bacteria that perform many essential functions in the biosphere, e.g. nitrogenfixation. Our bodies are covered with bacteria that make up our normal flora.
-Archaea: The Domain Archaea wasn't recognized as a major domain of life until quite recently. Until the 20th century, most biologists considered all living things to be classifiable as either a plant or an animal. But in the 1950s and 1960s, most biologists came to the realization that this system failed to accommodate thefungi, protists, and bacteria. By the 1970s, a system of Five Kingdoms had come to be accepted as the model by which all living things could be classified. At a more fundamental level, a distinction was made between the prokaryotic bacteria and the four eukaryotic kingdoms (plants, animals, fungi, & protists). The distinction recognizes the common traits that eukaryotic organisms share, such asnuclei, cytoskeletons, and internal membranes.
-Eukaryotes: have been broken down into four kingdoms: animals, plants, fungi, and protists or protoctists. The first three kingdoms are well-defined monophyletic groups, but the "Kingdom Protista" is not monophyletic; it contains organisms which are more closely related to members of other kingdoms than they are to other protists. It's also defined onthe absence of characters (i.e. no complex development from embryos, no extensive cell differentiation, etc.), which is considered poor form.
2. What theory explains the “unity and diversity of life”?
Evolutions theory. In biology the diversity and unity of life simply means that all living things came from ONE organism, so we are all alike but different. Then the diversity because even thoughwe have come from the same organism but from a different branch of the tree of life.
3. What is evolution? Who was the first person that proposed this theory?
Biological evolution is change in the characteristics of living organisms over generations.
Charles Darwin was the father of the theory of the evolution.
4. How do scientist go about finding answers to questions?
The scientific methodis a process for experimentation that is used to explore observations and answer questions. Scientists use the scientific method to search for cause and effect relationships in nature. In other words, they design an experiment so that changes to one item cause something else to vary in a predictable way.
5. What are the three requirements for an experiment to be valid?
Repeatability - theexperiment can be performed more than once with essentially the same results.
Resolution - the effect to be measured can be differentiated from extraneous signals.
Isolation - the measurement itself doesn't have a significant effect on the process under investigation.
6. What is the meaning of the word “theory” in science?
As used in science, a theory is an explanation or model based on observation,experimentation, and reasoning, especially one that has been tested and confirmed as a general principle helping to explain and predict natural phenomena.
7. What are the limitations of the scientific method?
1) Expensive
The scientific farming methods need huge investments in infrastructure, such as building of dams and irrigation pipelines. Not every farmers can afford it, especially farmersin less-developed countries.
2) Technical know-how
It is necessary for farmers to be educated and know to use machines wisely and correctly, however many farmers especially the ones in less-developed countries are less educated and have little technical know-how.
3) Patent of GM crops
Patent of GM crops are owned by few big private companies. Farmers have to buy seeds of GM food year after...