Chapter 1 bio229 - focus outline PDF

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1. Define microorganism/microbe. Know what types of organisms and agents this includes. -Microorganisms are organisms that are too small to see with the naked eye. There are bacteria, fungi, protozoa, some fungi and algae - Microbe is not considered organisms because they are not composed of cells → acellular. Such as viruses and some infectious agents 2. Contrast the Theory of Biogenesis with that of Spontaneous Generation. Be familiar with what kind of experiments were performed to support the currently accepted theory. Spontaneous Generation

Theory of Biogenesis

Is discredited belief that organisms can arise from non-living matter

-the unheated air or the broths themselves contains “vital force” necessary for spontaneous generation. -is the production of living things from other living things.

Experiments that helped disprove Spontaneous  Generation: In 1668, Francesco Redi used a simple experiment to show worms found on rotting meat originated from the eggs of flies, not from the decaying meat as supporters of spontaneous generation believed. In 1749, John Needham showed that flasks containing various broths (made by soaking nutrients such as hay or chicken in water) gave rise to microorganisms even when the flasks were boiled and sealed with a cork. Brief boiling was thought to kill all organisms, so organisms arose spontaneously. In 1768, Spallanzani’s experiments contradicted Needham’s experiment. No bacteria appeared after boiling. He boiled the broths for longer periods and he sealed the flasks by melting their

glass necks closed.--> broths were sterile. But if the neck was cracked, the broths rapidly became cloudy due to the growth of microorganisms.--> Microorganisms entered through the air -Theory of Biogenesis: Louis Pasteur filtered air through a cotton plug, trapping organisms. He demonstrated that the trapped microorganisms with a microscope were identical to those described by others who had been studying broths. When he dropped the cotton plug into a sterilized broth, the broth became cloudy from the growth of the microorganisms. He also demonstrated that sterilized broths remained sterile with swan-neck flasks. Microorganisms from the air were settled in the bends of the flask neck. Only the flasks were tipped so the microorganisms entered and grew. He also argued that unheated air or broths contained “vital force” necessary for spontaneous generation. Is the production of living things from other things 3. You should be familiar with the steps of the scientific method. -Scientific method is a process of formulating a testable explanation for a question, doing controlled experiments to test that explanation, and then publishing the methods, results, and conclusions. Steps:

-Making an observation about something and asking a question about the situation. -

Developing an explanation and then devising an experiment that tests the explanation Doing the experiment, collecting data, and drawing a conclusion Communicating the methods, results and conclusions

4. List some benefits of microbes:

Can compete with infectious microbes, thus helping to prevent disease; helps to digest food; promotes the immune system; Normal flora play an essential role in human health; Fermentation; Some microbes can degrade pollutants; Bacteria and fungi can produce foreign proteins including vaccines and enzymes

Virus used in gene therapy; Agrobacterium tumefaciens delivers genes into many genetically-modified plants Bacteria used to produce human insulin; bacteria then used as a factory to produce this protein safer and more efficiently Using microbes for the production of Biotherapeutics: Insulin, clotting factors, growth hormones, vaccines

5. State the germ theory of disease and discuss the advancements in microbiology that came about in the Golden Age of Microbiology. Many important advances were made during which time the field of microbiology blossomed, including discoveries that led to acceptance of the suggestion that microorganisms can cause the certain disease called the Germ theory of Disease. The advancements in microbiology that came about the Golden Age of Microbiology: led to developments of: -

Antimicrobial medication; vaccinations and immunity; improved surgical methods to prevent infection; also led to greater understanding in agricultural pathology,

6. Be familiar with how vaccines have made an impact on survival from various diseases (you do not have to remember a timeline but should be familiar with some major vaccines) Flu vaccine, Measles, HPV, Hepatitis, ... 7. Define pathogen, virus, viroid, prion Pathogen is disease-causing microbe, a noticeable impairment in body function; Prion is an acellular infectious agent consisting of protein

Viroid is an acellular infectious agent consisting of RNA Virus is an acellular infectious agent consisting of nucleic acid surrounded by a protein coat 8. Define the 3 domains of life and provide some basic characteristics along with an example of each. - Bacteria: +are single-celled prokaryotes; most bacteria have specific shapes (cylindrical, spherical round or spiral) + have rigid cell walls that contain peptidoglycan, a compound unique to bacteria +many of the bacteria can move using flagella, appendages that extend from the cell; +Asexual reproduction via binary fission +obtain energy from foods, but some can gain energy such as hydrogen sulfide; others are photosynthetic, they make cellular material using the radiant energy of sunlight. -Archaea: + + + + + + +

Are single-celled prokaryotes Have similar shapes, sixes , appearance to bacteria Multiply by binary fission Move primarily by means of flagella Have rigid cell walls Different groups of archaea use different energy sources Some are photosynthetic, harvesting the energy of sunlight to make cellular material + Ribosomal RNA nucleotide sequences differ from Bacteria + Have many biochemical properties + Cell walls lacking peptidoglycan

9. Describe the binomial system and use scientific names correctly. The binomial system is nomenclature developed by Carl Lonnaeus First name :genus Second name: species 10. List the roles of microorganisms in maintaining the life support systems of the Earth. List some roles that microorganisms play in the carbon cycle and nitrogen cycle. Are masters of recycling, and without them we would run out of certain nutrients The supply of O2 , and there are some microorganisms (microbes) Humans depend on certain microbes that convert N2 into a form of Nitrogen that other organisms can use (Nitrogen Fixation); Nitrogen is needed in building of Nucleic acid and proteins , without microorganisms playing this role many living things, we cannot exit 11. Estimate the size range of microorganisms and explain where they generally fall in terms of size comparisons with other particles or organisms. 100 nm- 10um

12. Describe how the Ti plasmid of Agrobacterium tumefaciens  functions in nature and how it was modified to make A. tumefaciens  a vector for the genetic engineering of plants. Plasmids used in genetic engineering; Ti (Tumor inducing) plasmid present in the bacteria Agrobacterium tumefaciens (plant pathogen) provides a naturally occurring transformation system. Deliver genes into many genetically-modified plants, transport through cell walls.

13. Briefly state why viruses might be effective vectors for the genetic engineering of animals. Because viruses can be used in gene therapy. Being as vectors mean virus are tools to transfer genes into other organisms 14. Distinguish between emerging and re-emerging infectious diseases and discuss the general causes of these with examples. Emerging infectious disease (EID) is an infectious disease that has been more common in the last 35 years. Many of these are new recognized Example: Ebola virus disease, congenital Zinka syndrome, hepatitis C, Lyme disease, acquired immunodeficiency syndrome,

Re-emerging infectious diseases are diseases that once were major health problems globally or in a particular country, and then declined dramatically, but are again becoming health problems for a significant proportion of the population Examples malaria and tuberculosis Changes in society bring opportunities for infectious agents to spread, resulting in an emerging disease. More mobile populations can contribute to disease emergence as people may inadvertently carry pathogens around the globe Newly infected international travelers could theoretically circle the globe, touch down in several countries, and expose many people before becoming ill themselves. Meanwhile, as suburbs of cities expand into rural areas, human populations come into closer contact with animals as well as the mosquitoes and other arthropods that normally feed on those animals. Consequently, people are exposed to pathogens they might not have encountered previously....