LO 1 Part 1 Flashcards
Define microbiology
The study of living things too small to be seen without a microscope
Micro organisms are called _____ or _____
Microorganisms; microbes
What is the biggest misconception about microbes?
That they are all harmful, more are helpful than harmful
What are the 8 branches of microbiology?
- Bacteriology - study bateria
- Virology - study viruses
- Immunology - study mechanisms of the body that protect against pathogenic microorganisms and foreign cells/substances
- Mycology - the study of pathogenic fungi
- Protozoology- study of pathogenic unicellular animal organisms
- GMOs/GEMs for industrial, pharmaceutical and agriculture
- Improvements of agriculture
- Gene therapy
What are some benefits of microorganisms?
- Maintenance of balance of environment (microbial ecology)
- Basis of food chain
- Digestion, synthesis of vitamins (microbiome)
- Manufacture of food and drink
Microorganisms do not intend to harm or destroy thing, they only want ______
To survive and grow
This person was the first to use a microscope for academic study, proposed that all living things are composed of cells (cell theory), and believed some forms of life could arise spontaneously from non-living matter
Robert Hooke (1665)
Describe Redi’s experiments (1668)
- Kept multiple flasks of decaying meat
- When flasks were isolated from flies, maggots never developed
- When meat was exposed to flies, maggots quickly developed
- Disproved Hooke’s spontaneous generation theory
This person first observed “animacules” (bacteria, yeast, protozoa) when looking at tooth scrapings and gutter water under a microscope
Antoni van leewenhoek
This person was the first to recognize the existence of tiny living particles that cause “catching” disease by direct or indirect contact
Girolamo Fracastoro
Describe Louis Pasteur’s flask experiments
- When the “swan-necked flasks” remained upright, no microbial growth appeared
- When the flask was tilted, dust from the bend in the neck seeped back and made the infusion cloudy with microbes
This person was a proponent of germ theory of disease, heating liquid to kill disease, helped develop rabies vaccine, and proposed antiseptic techniques to prevent contamination
Louis Pasteur
These two stressed the importance of hand-washing
Ignaz Semmelweis and Oliver Holmes
This person became concerned about post-operative infections and created the first aseptic technique for suegery
Joseph Lister UK (1867)
This person used simple staining techniques, postulated germ theory, used steam to sterilize media, used petri dishes, and determine bacteria to be distinct species (saw multiple bacteria in petri dishes)
Koch (1876)
What are Koch’s 4 steps to prove a microbe is the cause of a disease?
- The causitive agent must be found into every case if the disease
- The disease organism must be isolated from the lesions of the infected case and maintained in a pure culture
- The pure culture, inoculated into a susceptable experimental animal should produce the symptoms of the disease
- The same bacterium should be re-isolated in a pure culture from the intentionally infected animal
Who is considered the “father of oral microbiology” and posited the chemo -parasitic theory of caries (that they are caused by acids produced by oral bacteria following fermentation of sugars)
Willoughby D. Miller
Who created the first successful vaccine (smallpox)
Edward Jenner
By ______ bacteria had been recognized as the cause of numerous diseases, which lead to the establishment of _________
1900; infection control procedures
______ are the smallest microorganisms
Viruses
Nano bacteria are _____ times smaller than common bacteria
100
Most significant events in the early history of microbiology came down to these 3 things
- The development of microscopes
- Bacterial staining procedures
- Techniques for microbial lab cultures
We use microscopes to see individual microorganisms, but it is possible to see _____ with the naked eye
Colonies (yeasts/molds and matted strands of algae)
What is the zone of inhibition?
a clear circular area around antimicrobial discs in which bacteria are unable to grow
______ does not destroy all life forms, but does free surfaces of infectious material
Disinfection
_________ is defined as the destruction of all life forms – this includes using and autoclave
Sterilization
The bubonic plague is caused by _______ bacteria and caused _____ deaths between 1346-50
Yersenia pestis; 50 million
What is smallpox and what does it cause?
It is a deadly disease that can cause disfigurement and blindness
Caused by two airborne virus variants, variola major and variola minor
What causes seasonal influenza?
RNA viruses in the family Orthomyxoviridae
________ is a disease that exists permanently in a particular region or population (e.g. malaria in Africa)
Endemic
A(n) _________ is an outbreak of disease that attacks many people at about the the same time or spreads through many communities
Epidemic
A(n) _________ is an outbreak of disease that spreads globally
Pandemic
______ is an infectious inflammatory illness of the liver and is 50-100 times more infectious than HIV
Hepatitis B
This disease has high risk of death due to low blood pressure from fluid loss and typically 6 to 16 days after symptoms appear
Ebolaviruses
What are the 3 aspects of cell theory?
- All living things are made of cells
- Cells can only come from other cells
- All functions of a living thing are carried out in cells
What are the 2 main cell types and distinguishing features?
- Prokaryotic - lack membrane-bound organelles and nucleus, found in bacteria and Archaea, have strong cell walls which allows resistance to environmental changes
- Eukaryotic - membrane-bound organelles/nucleus, found in protists, plants, fungi, and animals
What is the Greek origin of prokaryotic?
“before nuclei”
How do bacteria reproduce?
Binary fission
Some prokaryotes move using _______
Flagella - allow bacteria to move toward more favourable environments
______ are hair-like structures that allow bacteria to stick to surfaces
Pili (fimbriae)
_______ easily attaches from the cell wall and enables gliding/sliding along solid surfaces
The slime layer
_________ is firmly attached to the cell wall and has an antiphagocytic function (protects bacteria from being engulfed by phagocytes)
Capsule
_______ are a means of survival when bacteria and nutrient supplies are low.
Endospores
Describe the features of bacterial spores (endospores)
- Help bacteria survive in extreme environments
- Resistent to heat, cold, drying, and most chemicals
- Survive many years and are resistant to disinfectants and boiling
- Can lay dormant for years until exposed to proper nutrients and other growth requirements (germinates into actively dividing cell)
- VERY DIFFICULT TO KILL
What is the Greek origin of Eukaryote?
True nucleus
What is the function of the cell membrane?
Transports substances in and out of the cell
(Some cells also conduct phagocytosis (engulf solids) or pinocytosis (engulf liquids)
What is the function of the cell wall?
Gives shape and strength to the cell to protect against osmotic imbalances (only in plants)
What is the function of chloroplasts?
Photosynthesis
What is the function of cilium?
Movement of substances
What is the function of the endoplasmic reticulum?
Protein synthesis (folds protein) and transportation of material around the cell
What is the function of flagellum?
Propulsion/motility
What is the function of the golgi apparatus?
Transfer of proteins to the exterior cell
What is the function of the mitochondria?
Synthesis of ATP
What is the function of the nucleolus?
Site of formation of ribosomal components
What is the function of ribosomes?
Protein synthesis
What is the function of vacuoles?
- Location of water
- storage site of amino acids, carbs, and proteins
- Dumping ground for cellular wastes
What is the function of lysosomes?
the digestive system of the cell, serving both to degrade material taken up from outside the cell and to digest obsolete components of the cell itself.
What are the 4 main types of protista and their characteristics?
- Algae - contain chlorophyll, photosynthetic aquatic organisms, part of the plankton population
- Protozoa - unicellular, non-photosynthetic, motile, require organic food,any form cysts and can serve as a site for spreading pathogens
- Fungi - non-photosynthetic, grow in dark/moist environments, few speculate pathogenic to humans
- Slime molds - parasitic and injure plants such as cauliflower, radish, and turnip
What are the 4 steps of mitosis?
- Prophase
- Metaphase
- Anaphase
- Telophase
What are the stages of meiosis?
- Prophase 1
- Metaphase 1
- Anaphase 1
- Telophase 1
- Prophase 2
- Metaphase 2
- Anaphase 2
- Telophase 2
What are 3 internal mechanisms of movement for microorganisms?
- The centriole
- The cytoskeleton
- Actin and tubulin proteins
What are 2 external mechanisms of movement for microorganisms?
- Flagella
- Cilia
Plants and animals require oxygen to breath, which means they are strict _________
Aerobes
Define aerobic respiration
A chemical reaction whereby organic compounds such as glucose are converted into energy for the cell using oxygen from the environment
Describe anaerobic respiration
- A process whereby respiration takes place without oxygen
- Occurs in groups of bacteria living in anaerobic environments (e.g. soil or stagnant water)
- Oxygen can be toxic to some anaerobic microorganisms or can inhibit growth
__________ is a metabolic process converting sugar to acids, gases, and/or alcohol using yeast or bacteria
Fermentation
Yeasts and many bacteria can use either _______ or ________ depending on the availability of oxygen
Fermentation; aerobic respiration
(Fermentation is less productive than aerobic respiration as an energy source for cells)
______ will die when exposed to atmospheric levels of oxygen - require fermentation
Obligate anaerobes
________ may or may not use oxygen when it is present depending on the levels of oxygen or fermentable material in the environment
Facultative anaerobes
________ may use oxygen, but only at low concentrations
Microaerophiles
Are viruses considered eukaryotes or prokaryotes?
Eukaryotes
(They have a membrane-bound nucleus)
