Question 1: In some developing countries, antibiotics can be purchased without a prescription. Why do you think this is done? What biological consequences would you predict?
Developing countries have a very weak drug regulation system, characterized with low number of physicians per person. Often, one physician has to attend to a large number of patients, and usually some communities live in places where physicians are rare and hospitals are not easily accessible. In addition, the fees charged for just seeing a physician is quite high for moist people to afford. The government thus allows the sale of some antibiotics in shops and chemist in order to allow a large number of persons to access them easily. The consequences of this are that the patients may take the wrong drug; frequency of over dose or under dose is high, drug abuse and misuse.
Question 2: why would the lives of multicellular animals be impossible if prokaryotic and protistan organisms did not exist?
Prokaryotic organisms are certainly the first living things to appear on earth, as per evolution theory. They are involved in various biodiversity activities which are all supportive of the multicellular organisms. Some of these include absorption of nutrients in the gut (animals) and roots in plants, nitrogen fixation in plants; bacteria form the basis for aquatic food chains, decomposition, while others aid in digestion in some specific animals. If none of the prokaryotes existed in the earth, the lives of the multicellular organisms would be endangered, and it is possible that they would also die out within a short period of time (Lengeler, Drews, and Schlegel 78).
Question 3: the discovery of penicillin revolutionized treatment of bacterial diseases; however, penicillin is now rarely prescribed. Why is this?
As a major evidence of bacterial evolution, most bacteria have become resistance to penicillin and its derivatives. This is caused by mutations in the bacterial genome (Lengeler, Drews and Schlegel 124). Bacteria have a highly mutating gnome owing to its ability to engulf extra chromosomal DNA such as plasmids, which normally transfer drug resistance genes between bacteria of even multiple species. Such mutations made it easy for penicillin resistance genes to be transferred into bacteria for several diseases, thus rendering penicillin ineffective for treatment (Lengeler, Drews, and Schlegel 124).
Question 4: what ecological consequences would occur if humans, using a new and deadly fungicide destroyed all fungi on earth?
Ecologically, fungi are one of the most important organisms as they are involved in a variety of activities (Lengeler, Drews, and Schlegel 207). Such activities include biodegradation and bio-deterioration, industrial and natural fermentation, bioremediation, production of food in agriculture, industrial development of biochemical. Of importance to some organisms is that some fungi are involved in transmission of genes in reproduction (Lengeler, Drews, and Schlegel 207). If human beings interfere in any or all of these activities through elimination of fungi, then most of these activities would be halted, and this interference with the ecology. The result is elimination of some food varieties, some organisms and industrial products. The long term effect is elimination of most living organisms of which human is a member.
Lengeler, Joseph W., Gerhart Drews, and Günter Schlegel. Biology of the prokaryotes. London: Georg Thieme Verlag, 2006. Print.