MicroBio Lecture Chapter 1

Endosymbionts

organisms living symbiotically inside a larger organism

Epidemiology

study of frequency and distribution of disease and other health-related factors in defined populations

What is immunization?

the stimulation of an immune response by deliberate inoculation with an attenuated pathogen

Characteristics of Eukaryotes

* Possess a nuclear membrane --> Fungi, Protozoa, and Algae

Algae

*Eukaryote *Contain chloroplasts and conduct photosynthesis *Base of the food web *Algal Bloom

Protozoa

*Eukaryote *Motile, single-celled organisms *Heterotrophs *May be free-living (ameba) or parasitic

Fungi

*Eukaryote *Nonmotile *Absorb nutrients from surrounding *Grow as single cells or as filaments *Can cause disease, particularly in immunocompromised

Characteristics of Prokaryotes

*Lack a nuclear membrane --> Bacteria and Archaea

Viruses

*Not Prokaryote or Eukaryote *Noncellular *Genetic material (DNA or RNA)- takes over the metabolism of a cell to generate more viruses *Can cause disease --> also used in biotechnology

Bacteria

*Prokaryote *0.2-20um *may grow as single cells, filaments, communities *ubiquitous (existing everywhere)

Archaea

*Prokaryote *Genetically distinct from bacteria *Extremophiles (methanogens) *Nonpathogenic

Diseases that changes cultural practices...

*Tuberculosis *Leprosy *Smallpox *Bubonic Plague (Renaissance) *HIV

What is a microbe?

*a living organism that requires a microscope to be seen --> this definition has contradictions ---> some microbes can be seen w/o microscope (amoebas), some form multicellular assemblages that can be seen w/o microscope (mycelia, biofilms), and some organisms need a microscope to be seen but isn't a microbe (mites)

What are the four points of Koch's Postulates?

1. The Microbe is found in all cases of the disease but is absent from healthy ones 2. The microbe is isolated from the diseased host and grown in pure culture 3. When the microbe is introduced into a healthy, susceptible host, the same disease occurs 4. The same strain of microbe is obtained from the newly diseased host

Which of the following did Ignaz Semmelweis demonstrate to be an important means of preventing disease transmission? A. Handwashing B. Autoclaves C. Antibiotics D. Vaccines

A. Handwashing

Which of the following scientists accidentally discovered that an attenuated strain of a microbe can initiate immunity? A. Louis Pasteur B. Edward Jenner C. Joseph Lister D. Alexander Fleming

A. Louis Pasteur

Today, most cases of rabies involve wildlife such as raccoons, foxes, vampire bats, and so on, as well as stray dogs. Small rodents only very rarely get rabies. This is probably a result of what? A. the primary mode of rabies virus transmission B. the fact that rabies infects only mammals C. the intrinsic immunity of rodents to viruses D. the small brain size of rodents E. the life span of rodents being shorter than the incubation time of the disease

A. the primary mode of rabies virus transmission --> As mammals, small rodents are technically susceptible to rabies. However, they are unlikely to survive a bite by a rabid predator—especially long enough to develop and transmit the disease themselves

Who discovered penicillin as a contaminant on a plated culture of Staph and noticed no growth around the contaminant?

Alexander Fleming

Who was the first person to observe single-celled microbes?

Antoine van Leeuwenhoek

Who was the microbiologist who developed the rabies vaccine? A. Edward Jenner B. Louis Pasteur C. Robert Koch D. Alexander Fleming

B. Louis Pasteur

Which scientist was credited with first generating the image of an X-Ray of DNA? A. Frederick Sanger B. Rosalind Franklin C. Francis Crick D. James Watson

B. Rosalind Franklin --> Rosalind Franklin specialized in X-ray crystallography and diffraction, and she is credited with this photograph of DNA. This data was interpreted by James Watson and Francis Crick, who together proposed the three-dimensional model of DNA.

The vaccine preparations administered to Joseph Meister contained attenuated rabies virus. This means that the virus was which of the following? A. genetically engineered to be avirulent B. weakened but could still elicit immunity C. completely inactivated ("dead") D. mutated to cause disease in an alternate host

B. Weakened but could still elicit immunity

Which theory proposes how the first eukaryotic cells evolved? A. Biogenesis B. Germ theory C. Endosymbiotic theory D. Spontaneous generation

C. Endosymbiotic theory -->explanation to the origin of eukaryotic cells and how they arose from prokaryotic cells

Which of the following scientists proposed that mitochondria and chloroplasts evolved by endosymbiosis from prokaryotic cells? A. Carl Woese B. Martinus Beijerinck C. Lynn Margulis D. Sergei Winogradsky

C. Lynn Margulis

Which of the following eukaryotic structures most closely resembles a prokaryotic cell? A. Golgi complex B. Nucleus C. Mitochondrion D. Endoplasmic reticulum

C. Mitochondrion

Who discovered that some organisms in Yellowstone have very different genomes than others?

Carl Woese

How are microbes classified?

Classified as members of a species; according to genetic relatedness

Which of the following statements is supported by the model illustrated below? Choose one or more: A. Archaea evolved from endosymbiosis with a proteobacterium. B.Fungi were once photosynthetic but lost their chloroplasts. C.Mitochondria are descended from ancestral endosymbiotic proteobacteria. D.Modern cyanobacteria descended from chloroplasts. E.Having mitochondria is a prerequisite for acquiring chloroplasts

Correct Choices: C.Mitochondria are descended from ancestral endosymbiotic proteobacteria E.Having mitochondria is a prerequisite for acquiring chloroplasts.

Which of the following are prokaryotes? A. Protozoa B. Algae C. Fungi D. Archaea

D. Archaea

Who was the first person to vaccinate for smallpox?

Edward Jenner inoculated people with cowpox which provided immunity for smallpox

Although the rabies vaccine was effective in producing immunity against the disease, the causative agent had yet to be identified. In fact, the first evidence for the existence of viruses came from experiments using...

Filtration --> Because viruses are 10 to 100x smaller than bacteria, the two can be separated by using filtration

Who used statistics to quantify role of disease in population mortality and improved public health in England?

Florence Nightingale

Who purified penicillin?

Howard Florey and Ernst Chain

Who promoted handwashing with chlorine (an antiseptic) prior to assisting with childbirth?

Ignaz Semmelweis

Who began sterilizing instruments and wounds to create an aseptic environment for surgery?

Joseph Lister

Who was the person who brought the idea of vaccination from Turkey?

Lady Mary Montagu

Who performed the sealed flask experiment?

Lazzaro Spallanzani

Who discovered pathogens could be attenuated?

Louis Pasteur

Who performed the swan neck flask experiment?

Louis Pasteur

Who proposed that eukaryotic cells merged with bacteria to form composite cells?

Lynn Margullis

Who studied the tobacco mosaic virus and concluded it was cause by something small enough to pass through a filter?

Martinus Beijernick

How does microbes effect a geochemical cycle?

Microbes fixing both carbon and nitrogen into organic matter

What are some of the contributions of microbes?

Microbes have shaped our: *Atmosphere *Geology *Energy Cycles *Contribute to air we breathe *Fix nitrogen into useable forms by plants *Make essential vitamins --> B12 *Primary producers in food webs

What is an attenuated pathogen?

Microbes that have reduce virullence, but provokes an immune response, providing immunity

What is a geochemical cycle?

Movement of nutrients within and among the atmosphere, lithosphere, and hydrosphere (also involved weathering, erosion, volcanoes, sedimentation, etc.)

Who was the first person to build a compound microscope? --> Only obtained 30x mag.

Robert Hooke

Who recognized the need for scientific method for identifying microbial cause of infectious disease?

Robert Koch

Who was credited for discovering that DNA forms a double helix?

Rosalind Franklin

Who studied microbes in wetlands and found that microbes that only feed on inorganic minerals (lithotrophs) and developed enrichment media

Sergei Winogradsky

What is Koch's Postulates?

Set of criteria that establish whether a particular organism is the cause of a particular disease

Spontaneous generation

The mistaken idea that living things arise spontaneously, from nonliving sources (without parent organisms)

Who identified the filterable agent by crystalizing the ineffective particle from infected tobacco leaves?

Wendell Stanley