Quiz Chapter 6 Flashcards
Thermoduric medophiles
Can survive brief high temp during inadequate pasteurization and canning. Can result in food spoilage by thermodruric medophiles.
Mycobacterium leprae
Grows in cooler area of body- extremities. Facial area, grond area. Grows slowly.
Mesophiles
Temperature is moderate. Microbes optimum temp between 20-40 C
Human pathogens- internal body temperature
Culture
Growth of microorganism in a culture medium.
Pure culture
Descendants of a single cell and separated from others.
Colony
Aggregation of cells arising from a single parent cell.
Biofilm
Collection surface microbes living in a complex community.
Physical
Temp./PH of medium/ light/ osmosis pressure.
Chemical
Water/ trace/ nitrogen/ O2
Minimum growth temperature
Lowest temperature at which spices will grow. Slow metabolism.
Optimum growth
Species grows best at this temperture. Fast growth.
Maximum growth
Highest temperature at which growth is possible.
Syphilis
Grows in rabbits scrotum
M. Lepra
Grows in Armadilo foot
Neutrophils
Preferred PH range 6.5-7.5 internal cell PH.
Acidophilus
Optimum PH below 5.5 preferred by many fungi
Acid tolerant microbes
H. Pylori neutralizes stomach acid by secreting bicarbonate and urease an enzyme that converts urea to ammonia which is alkaline.
Alkalinophiles
Opt. pH above 8.5
Found in alkaline soil and lakes.up to 11.5
Obligate
Requires oxygen for growth
Acidophilies
Opt. PH below 5.5
Thiobacillis ferrocidans
Medophilies
Most human pathogen because they like moderate temperature.
Osmosis
High to low
Diffusion of water across a selectively permeable to water molecules
Remember
Living system is always water. During osmosis water movement is to the dryer side of the membrane.
Plasmolysis
The procession which cell lose water in a hypertonic solution. If placed in a hypertonic solution then pressure increases to the point where the protoplasm of a cell wall peels away.
Osmotic lysis
Occurred when the cell butts due to an osmotic imbalance that has caused excess water to move into cell. It occurs in hypotonic environment. Where water moves into the cell by osmosis.
Hypertonic solution
Lower inside
Hypotonic solution
Less solution outside
Water in microbacterium tuberculosis growth
Tap water contains trace elements it is preferred over deionized water.
Mycobacterium tuberculosis growth are abundant in soil and water. The cell can retain water and withstand dry conditions.
Adult urogenital system and yeast infection
Woman have natural acidity results from fermentation of carbs by normal resident bacteria.
If disrupted by antibiotics it results in higher PH and it allows yeasts to grow and lead to a yeast infection.
Obligate acidophilus
Require acidic environment and die if the pH approaches 7.0, acid tolerant microbes merely survive in acid without preferring it.
Thiobacillus
Grows in 0-2 pH in organic sulfur compounds.
Derives energy from oxidation of ferries iron to ferric io and reducded suffer compounds to sulfur acids.
Most human pathogens belongs to which group?
Medophiles
because they like moderate temperatures.
Blood agar and hemolysin
Difference between
Alpha, beta and gamma hemolysin.
Alpha-
Streptococcus pneumonia
Partially digests ( loses) blood cells, producing around its colonies a greenish brown discoloration denoted alpha-hemolysis.
Chemically defined medium
Chemical composition is known
- has all required nutrients
(Glucose, salts) for the target microbes
- some may contain vitamins/ amino acids in known quantity.
