Microbiology exam 1

What is a microbe?

a microbe or organism is a living thing that is too small to see with the naked eye.

They are ubiquitous, meaning they can be found anywhere

they can be helpful, harmful, or neither.

How do we see microbes?

a microscope is a tool that uses refraction to bend light using lenses.

What is a germ?

a germ is a pathogen, an organism that causes a disease. not all pathogens are microscopic.

what did prehistoric humans thing believe disease was the result of?

angry gods, poverty, and other ridiculous things.

what are a result of microbial fermentation

pickles, cheese, yogurt, bread, soy sauce, beer, wine

what is microbial fermentation?

bacteria, mold, or yeast. Archaeologists found evidence of fermented beverages in jars from as earyly as 7000 bc.

What was the cloaca Maxima or “greatest sewer” ?

An engineering marvel that carried waste away from the city and into the river tiber. The ancient latrines(toilets) emptied into the cloaca maxima.

who was hippocrates?

known as the father of western medicine, believed that disease had natural, not supernatural causes.

who was thucydides?

the father of scientific history, he observed that survivors of the athenian plague were subsequently immune to the infection.

who was Marcus Terentius Varro?

He proposed that disease could be caused by certain minute creatures which cannot be seen by the eyes.

who invented the first microscope?

Hans and Zacharias. Evidence even suggest that they developed the first telescope.

who invented the microscope powerful enough to view microbes?

Anton Van Leeuwenhoek in 1675

who is Lous Pasteur?

he is credited with numerous innovations that advanced the fields of microbiology and immunology, like Pasteurization.

Who is Robert Koch?

He identified the specific microbes that caused specific disease, such as anthrax, cholera, and tuberculosis.

What tools do we use in lab to see microbes?

A Petri dish and a inoculation loop to streak bacteria on the Petri dish.

What is taxonomy?

Taxonomy is the classification and naming of a living organism.

What did Carolus Linnaeus do?

He developed a new system for categorizing plants and animals.

How did Carolus Linnaeus name microbes?

He used a system of binomial nomenclature, a two word naming system, for identifying organisms by their genus and species.

what is a phylogeny?

A evolutionary relationship shown across time?

What is based on Morphology?

prior phylogenis. Morphology are observable characteristics.

what did carl woese and george fox discover?

Appeared to be a living record of the evolution of organisms using small subunit ribosomal RNA

What are the three domains?

Bacteria, Archea, Eukarya

Bacteria and archea contain all prokaryotic organisms and eukarya contains all eukaryotic organisms.

What are Biosafety Levels (BSL)?

standards that must be met when working with microorganism.

a BSL-1 organism, like E. coli, is unlikely to cause disease in a healthy individual

A BSL-4, like ebolavirus, is incredibly contagious and there is no vaccine or cure.

How do microorganisms differ from eachother?

In size, structure, habitat, metabolism, and many other characteristics.

While some microbes are unicellular, made up of a single sell. Some are multicellular, composed of many sells, and, acellular, not composed of cells.

whats the unified cell theory?

it states that all living things are composed of one or more cells; that the cell is the basic unit of life; and that new cells arise from existing cells.

What are the common bacterial shapes?

Coccus- spherical

Bacillus- rod shaped

vibrio- curved rod

spirillum- spiral

spirochete- more tightly coiled spiral

Whats the difference between bacteria and archaea

visually, they are similar. However, they differ metabolically, genetically, and structurally, and no archaeans are known to be human pathogens.

What does the domain Eukarya contain?

All eukaryotes, including uni- or multicellular eukaryotes such as protists, fungi, plants, and animals. Eukaryote cells contain a nucleus.

what is an assorted diatom?

a kind of algae, live in annual sea ice in antarctica. Diatoms range in size from 2 um to 200 um.

Whatv is Giardia Lamblia?

An intestinal protozoan, a type of protist, parasite that infects humans and other mammals, causing Giardia, which is characterized by severn diarrhea. Giardia is contracted by ingesting G. lambia contaminated water.

What are viruses?

Acellular microorganism, which means they are not composed of cells.

A virus consists of proteins and genetic material, either DNA or RNA, but never both, that are inert outside of a host organism.

By incorporating themselves into a host cell, viruses can co-opt the host’s cellular mechanisms to multiply and infect other hosts.

What are some fields in microbiology?

Bacteriology: study of bacteria

Mycology: study of fungi

Protozoology: study of protozoa

parasitology: study of helminths and other parasites

virology: study of viruses

immunology: study of the immune system

what is wavelength?

wavelength is the distance between one peak of a wave and the next peak

What is brightfield microscopy and darkfield microscopy?

brightfield microscopy renders a darker image on a light background

darkfield microscopy increases contrast, rendering a brighter image on a darker background

what is amplitude?

the height of each peak (or the depth of each trough)

what is frequency?

the rate of vibration of the wave, aka the number of wavelengths within a specified time period

what are the interactions of light?

light waves interact with materials by being reflected, absorbed, or transmitted

reflection: when a wave bounces off a material

absorbance: when a material captures the engery of a light wave.

transmission: when a wave travels through a material

diffraction: light waves interacts with small objects or openings by bending or scattering.

what is refraction?

occurs hen light waves change direction as they enter a new medium.

what is refractive index?

a material is the extent to which it slows transmission speed relative to empty space.

what is focal point & focal length?

focal point is the image point when light entering the lens is parallel

focal length is the distance to the focal point

what does the human eye contain?

the human eye contains a lens that allow us to see images.

The lens focuses the light reflecting off the objects in front of the eye onto the surface of the retina, which acts like a screen in the back of the eye.

what is visible light?

one form of electromagnetic radiation, a type of energy that is all around us.