Final Exam Ch 1 Flashcards
(33 cards)
Microorganisms are found in each of the three domains of life
Archaea, Bacteria, Eukarya
prokaryotes:
- Bacteria and Archaea
- Their cells lack a nucleus
eukarya
- Eukaryotes
- cells have a nucleus
Bacteria Domain
- Are found in nearly every habitat on earth
- Most bacteria are harmless or helpful, but some are pathogens (causing disease in humans and other animals)
- bacteria are prokaryotic because their genetic material (DNA) is not house with a true nucleus
- cell walls contain peptidoglycan
Archaea Domain
- unicellular prokaryotic organisms
- Unlike most bacteria, archaea cell walls do not contain peptidoglycan and instead are composed of pseudopeptidoglycan
- Like bacteria archaea are found in nearly every habitat on earth, even extreme environments that are very cold, very hot, very basic, or very acidic
- Some live in the human body, but none have been shown to be human pathogens
Eukaryotic Domain
- Protists, fungi plants, animals, algae
- A major defining characteristic of eukaryotes: their cells contain a nucleus
Protists
- informal grouping of eukaryotes that are not plants, animals, or fungi
- All Protozoa are examples of protists protozoa are protests that make up the backbone of many food webs by providing nutrients for other organisms
- Some algae are protists
- Algae: photosynthetic organisms that extract energy from the sun and release oxygen and carbohydrates into their environment
fungi
- fungi are not photosynthetic
- Cell walls are usually made out of chitin rather than cellulose
- Some are multicellular some are unicellular (like yeast)
- Mold is a type of fungus
Helminths
multicellular parasitic worms
*Example: Guinea Worm —> Dracunculus medinensis
*Causes dizziness, vomiting, diarrhea, and painful ulcers on the legs and feet when the worm works its way out of the skin
*Infection occurs after a person drinks, water containing water fleas infected by guinea worm larvae
viruses
a cellular microorganisms, which means they are not composed of cells
* or neither eukaryotic or prokaryotic
* consists of proteins and genetic material, either DNA or RNA, but never both
Hierarchy of classification
domain, kingdom, phylum, class, order, family, genus, and species
Hippocrates
considered the “father of Western medicine”
* believed that diseases had natural not supernatural causes
* Hippocratic Corpus: a collection of text that make up some of the oldest surviving medical books
Thucydides
considered the father of scientific history because he advocated for evidence based analysis of causing effect reasoning
* introduced the idea of immunity after observing that survivors of the Athenian plague were immune to the infection
Marcus Terentius Varro:
: a prolific Roman writer, who was one of the first people to propose the concept that microorganisms can cause disease
* “ disease could be caused by certain minute creature… which cannot be seen by the eye”
Antonie van Leeuwenhoek
the first to develop a lens powerful enough to view microbes in 1675
* he observed single celled organisms describing them as “ animalcules” and “wee little beasties” swimming in a drop of rainwater
* FATHER OF MICROBIOLOGY
louis pasteur
French Chemist
* demonstrated that fermentation is caused by microorganisms
* invented pasteurization, a process used to kill microorganisms responsible for spoilage
* developed vaccines for the treatment of diseases, including rabies
robert koch
developed a set of postulates for determining whether a particular disease is caused by a particular pathogen
Carolus Linnaeus
the most famous early taxonomist
* he divided the natural world into three kingdoms: animal, plant, and mineral (mineral kingdom was later abandoned)
* The names of the levels in his original taxonomy were kingdom, class, order, family, genus, and species
Ernst Haeckel:
- proposed to more kingdoms (Protista for unicellular organisms and Monera for unicellular organisms whose cells lack nuclei, like bacteria)
Robert Whittaker
- Proposed adding another kingdom - Fungi
- Whitaker held another categorization above the kingdom level — the empire or super kingdom level — to distinguish between organisms that have membrane-bound nuclei in their cells (eukaryotes) and those that do not (prokaryotes)
- Empire Prokaryota contained just the kingdom Monera
- Empire Eukaryota contained the other four kingdoms: fungi, Protista, plantar, animalia
Ignaz Semmelweis (1818-65)
was a proponent the importance of handwashing to prevent transfer of disease between patients by physicians
John Snow
conducted studies to track the source of cholera (found that it was transmitted via drinking water)
* represents the first known epidemiological study
* father of epidemiology
Joseph Lister
developed procedures for the proper care of surgical wounds and sterilization of surgical equipment
Robert Hooke
first, to observe dead cells by observing a sample of cork through his microscope
