Biology 192 Exam 2
why some strict parasitic bacteria like typhus and viruses like rhinovirus has a narrow cardinal temperature range.
Bacteria like typhus and viruses like rhinovirus can only survive a few degrees below or above the hosts body temperature range. Higher 32-38 degrees, lower 32-35 degrees
Aerobes
Bacteria that require oxygen to grow
when organisms are grown in culture media they often produce acids that eventually interfere with their growth. what is added to the medium to maintain the proper pH?
Buffer
name the 6 essential nutrients for an organism
C, H, O, N, P, S
name the 6 inorganic elements that makeup 96% of the dry weight of the cell
C, H, O, N, S, P
Name the 4 organic compounds that make up 97% of the dry weight of the cell
Carbohydrates Lipids Protein Nucleic acids
if an archeae is placed in distilled water what will happen and why?
Cell wall will protect it from exploding as in the case of bacteria
Saprobes
Dead organic matter
give an example where this process is helpful for our society
Food preservation industry
Thermophiles can _____________
Grow in soil and water associated with volcanic activity, organic compost piles.
neisseria gonnorrohoeae and neisseria meningitdis grow mor rapidly in the presence of ______
Iron
Capnophiles
Microbes that require high CO2 conditions
generation time
the time required for the complete cycle to form two daughter cells from a parent cell via binary fission
obligate halophiles
those that grow in up to 30% salt, require high osmotic pressure
obligate parasites
unable to grow outside of a living host
Alkanophiles, such as natromonas grow at ______ pH
up to 12
Photoautotrophs
use photosynthesis
exponential growth
the growth pattern in the bacterial population produces a larger number of cells, useful to express using exponents or log
generation
the number of fission cycles to form 2 daughter cells from a parent cell 2n, n is the generation number
microbes like halobacterium and halococcus must be grown in a medium that is _____ but can grow at _______. Staphylococcus aureus can grown on a _____.
- 25% NaCl -9% NaCl -NaCl media ranging from 0.1% to 20%
in the case of hypertonic solution used as IV, the tonicity of the solution is ___ than the bodys plasma. so the net movement of water is _______________
- Lower _ moving from intravascular to extravascular spaces eventually into the cells of the tissue. in this case the body moves water from intravascular spaces to cells to dilute the higher concentration of electrolytes in the cells.
If a microbe is placed in a higher solute concentration medium or ______ medium the cellular water passes out through _______________. This osmotic loss of water is called_________
- hypertonic - cell membrane in surrounding - plasmolysis
MRsa carrier state is typically diagnosed use PCR by ________, rather than culture
- nasal swab
in the case of isotonic solution used as IV, the tonicity of the solution is ___ at the body's plasma. so the net movement of the water is _______.
- same - very little between body tissue and the blood vessel
Name some bacterial species and the diseases cause by them, when carbon dioxide helps in their isolation
-Neisseria gonorrhea -Streptococcus pneumoniae
very few grow at a pH ___________. obligate acidophikes like euglena mutabilis is algae that grow between ___ and __ pH. Thermaplasma, and archae grow between ___ and ___ pH.
-less than 6 - 0 and 1 -1 and 2
Psychrophiles are capable of growing at _____________________
15 degrees with optimum at 0
Many thermophiles organisms have an optimum growth temperature of _____________, cannot grow below a temperature of about _______.
45-80 60
most bacteria grow best at
6-8 pH
water makes up ________ of all compounds
70%
These bacteria grow between _______________. Researchers sometimes use an autoclave to isolate them as most other bacteria are killed that these temperatures.
80-120 degrees
binary fission
A form of asexual reproduction in single-celled organisms by which one cell divides into two cells of the same size
Commensalism
A relationship between two organisms in which one organism benefits and the other is unaffected
Parasitism
A relationship between two organisms of different species where one benefits and the other is harmed
Mutualism
A relationship between two species in which both species benefit
extreme halophiles
An organism that lives in a highly saline environment, such as the Great Salt Lake or the Dead Sea.
Parasites
An organism that lives in or on another organism, deriving nourishment at the expense of its host, usually without killing it
Mesophiles have adapted to live in the ______________________. The optimum temperature of pathogenic bacteria is about 37 degrees C
Animal, plants, soil and water
One group of bacteria which is now a separate domain ________ includes organisms that grow _____________. These organisms are called _______________ __________.
Archaea Extreme T Extreme Thermophiles
What are the three cardinal temperatures
Minimum T - lowest temp that allows the continuous growth and metabolism of the microorganism Maximum T - highest temp that allows the continuous growth and metabolism for the microorganism Optimum T - small range of the temp between the highest and the lowest temp that allows the maximum growth and metabolism of the microorganism
What is meant by cardinal temperature
The range of temperatures for the growth of a given microbial species can be expressed as three cardinal temperatures
why are molds and yeast, the most common cause of spoilage of pickled foods?
They can survive in moderate acidity
What are biofilms?
a thin, slimy film of bacteria that adheres to a surface.
pH is the ______ or _____ of a solution
acidity alkalinity
antagonism
active hostility or opposition
Pathogens
any agent that causes disease
What is the significance for zinc
binding factor
facultative anaerobes
can grow with or without oxygen
Phototrophs
can use visible light rays as an energy source
aerotolerant anaerobes
cannot use oxygen for metabolism, but can survive in an oxygen-containing environment
What is the significance for sodium
cell transport
describe the steps in the formation of a biofilm
colonizer initially attaches to a surface the other microbes then attach to those bacteria or polymeric sugar or protein substance secreted by the microbial colonizers. attached cells are stimulated to release chemicals as the cell population grows
CFUs
colony forming unit, a colony forming unit is a unit in microbiology to estimate the number of viable bacteria or fungal cells in a sample
what are some of the precautions that must be considered to prevent the spread of MRSA?
contact isolation, gown and gloves, private rooms, daily cleaning and separate frequently used medical equipment.
What is the significance for iron
cytochrome proteins in respiration
What is the significance for magnesium
found in chlorophyll and stabilizes membranes and ribosomes
heterotrophs
get carbon from an organic sorce
Chemoheterotrophs
get energy and carbon from organic compounds
Thermoduric microbes are ________________
grown at temperatures higher than 45 degrees
Microorganisms obtain almost all their nutrients in solutions from the surrounding water. Because their composition is _____ to the water.
hypertonic
in reality, why the population bacteria does not maintain it potential growth rate
in a closed system there are numerous factors that limit the exponential growth rate of bacterial population.
what structure is acting as a semipermeable membrane
in terms of the use of IV fluids of various tonicity, the walls of the blood vessels are acting as a semipermeable membrane to exclude the large solutes, not water.
symbiotic
involving a close relationship of mutual dependence
how is the PCR testing better than culture?
it detects bacterial DNA in the sample and is a very rapid test.
Anaerobes
lack the metabolic enzyme systems for using oxygen in respiration
Endoparasites
live inside the host
Ectoparasites
live on the body
Synergism
members cooperate and share nutrients
why proteus is the most common cause of infection in the urinary system?
metabolism of the urea is one way that proteus can neutralize the acidity of urine to colonize and infect the urinary system.
Chemotrophs
obtain energy from chemicals
Nonsymbiotic
organisms are free-living; relationships not required for survival
Barophiles
organisms that live under extreme pressure
What is the significance for potassium
protein synthesis and membrane function
you cooked some soup kept in the refrigerator and forgot about it . After a few weeks, you found the soup was in the refrigerator it was spoiled by __________, as these types of organisms slowly degrade food at lower temperatures like in the refrigerator.
psychrotrophs
They are much more common than psychrophiles and most likely encountered at low temperature food spoilage are called ___________. Examples of these types of bacteria are _______________________________. They can cause foodborne illnesses
psychrotrophs staphylococcus aureus and listeria monocytogenes
Microaerophiles
require oxygen concentration lower than air
faculatative halophiles
resistant to salt, they do not require high salt concentration, but are able to grow at salt concentration up to 2 percent, some can even tolerate 15 percent
autotrophs
self-feeder, gets carbon from an inorganic source
What is the significance for calcium
stabilize cell wall and endospore
What is quorum sensing?
the ability of bacteria in a biofilm to communicate with each other and coordinate their activities
Antibiosis
the association between two organisms in which one is harmful to the other