Term
|
Definition
process by which chemical substances (nutrients) are acquired from the environment and used in cellular activities |
|
|
Term
|
Definition
Essential nutrients must be provided to an organism; Two categories of essential nutrients: macronutrients, micronutrients (or trace elements) |
|
|
Term
|
Definition
required in large quantities; play principal roles in cell structure and metabolism Proteins - nitrogen, carbohydrates - carbon |
|
|
Term
Micronutrients (or trace elements) |
|
Definition
required in small amounts; involved in enzyme function and maintenance of protein structure; Manganese, zinc, nickel; nutrients |
|
|
Term
|
Definition
contain carbon and hydrogen atoms and are usually the products of living things; Methane (CH4), carbohydrates, lipids, proteins, and nucleic acids |
|
|
Term
|
Definition
atom or molecule that contains a combination of atoms other than carbon and hydrogen; Metals and their salts (magnesium sulfate, ferric nitrate, sodium phosphate), gases (oxygen, carbon dioxide) and water |
|
|
Term
Chemical Analysis of Cell Contents |
|
Definition
70% water; Proteins; 96% of cell is composed of 6 elements: Carbon, Hydrogen, Oxygen, Phosphorous, Sulfur, Nitrogen |
|
|
Term
|
Definition
must obtain carbon from an organic form made by other living organisms; proteins, carbohydrates, lipids, and nucleic acids |
|
|
Term
|
Definition
uses CO2 (inorganic gas) as its carbon source; not nutritionally dependent on other living things |
|
|
Term
|
Definition
Organic compounds that cannot be synthesized by an organism because they lack the genetic and metabolic mechanisms to synthesize them; Growth factors must be provided as a nutrient; Essential amino acids, vitamins, nucleotides |
|
|
Term
|
Definition
Main determinants of nutritional type are: Carbon source – heterotroph, autotroph;Energy source -Chemotroph – gain energy from chemical compounds;Phototrophs – gain energy through photosynthesis |
|
|
Term
|
Definition
Oxygenic photosynthesis; Anoxygenic photosynthesis |
|
|
Term
|
Definition
lithoautotrophs survive totally on inorganic substances; methanogens, a kind of chemoautotroph, produce methane gas under anaerobic conditions |
|
|
Term
|
Definition
Aerobic respiration; two categories: saprobes and parasites |
|
|
Term
|
Definition
free-living microorganisms that feed on organic detritus from dead organisms; Opportunistic pathogen; Facultative parasite |
|
|
Term
|
Definition
derive nutrients from host; Pathogens; Some are obligate parasites |
|
|
Term
|
Definition
does not require energy; substances exist in a gradient and move from areas of higher concentration toward areas of lower concentration; Diffusion; Osmosis – diffusion of water; Facilitated diffusion – requires a carrier |
|
|
Term
|
Definition
requires energy and carrier proteins; gradient independent; Active transport; Group translocation – transported molecule chemically altered; Bulk transport – endocytosis, exocytosis, pinocytosis |
|
|
Term
|
Definition
Net Movement of Molecules Down Their Concentration Gradient (Passive Transport) |
|
|
Term
|
Definition
Diffusion of Water (Passive Transport) |
|
|
Term
|
Definition
Water concentration is equal inside and outside of the cell, thus rates of diffusion are equal in both directions |
|
|
Term
|
Definition
Net difussion of water is into the cell; Cell membrane: causes cell to swell and may burst if there is no mechanism to remove the water; Cell wall: swells the protoplast and pushes it tightly against the cell wall, preventing the cell from bursting |
|
|
Term
|
Definition
Water difuses out of the cell; Cell membrane: causes it to shrink and become distoreted; cell wall: causes plasmolysis(shrinks the cell membrane away from the wall) |
|
|
Term
|
Definition
Requires a carrier(Passive transport) |
|
|
Term
Carrier-mediated active transport |
|
Definition
Atoms or molecules are transported into or out of the cell by specialized receptors, driven by ATP or other high energy molecules |
|
|
Term
|
Definition
transported molecule is chemically altered |
|
|
Term
|
Definition
bringing substances into the cell through a vesicle or phagosome (bulk transport); Phagocytosis, pinocytosis |
|
|
Term
|
Definition
ingests substances or cells(bulk transport) |
|
|
Term
|
Definition
ingests liquids(bulk transport) |
|
|
Term
|
Definition
totality of adaptations organisms make to their habitat |
|
|
Term
|
Definition
Environmental factors affect the function of metabolic enzymes; Factors include: Temperature, Oxygen requirements, pH, Osmotic pressure, Barometric pressure |
|
|
Term
|
Definition
Minimum temperature – lowest temperature that permits a microbe’s growth and metabolism; Maximum temperature – highest temperature that permits a microbe’s growth and metabolism; Optimum temperature – promotes the fastest rate of growth and metabolism |
|
|
Term
3 Temperature adaptation groups |
|
Definition
Psychrophiles, Mesophiles, Thermophiles |
|
|
Term
|
Definition
optimum temperature below 15oC; capable of growth at 0oC |
|
|
Term
|
Definition
optimum temperature 20o-40oC; most human pathogens |
|
|
Term
|
Definition
optimum temperature greater than 45oC |
|
|
Term
|
Definition
Oxygen:As oxygen is utilized it is transformed into several toxic products: Singlet oxygen (1O2), superoxide ion (O2-), peroxide (H2O2), and hydroxyl radicals (OH-); Most cells have developed enzymes that neutralize these chemicals: Superoxide dismutase, catalase; If a microbe is not capable of dealing with toxic oxygen, it is forced to live in oxygen free habitats; Carbon dioxide: All microbes require some carbon dioxide in their metabolism |
|
|
Term
|
Definition
utilizes oxygen and can detoxify it |
|
|
Term
|
Definition
cannot grow without oxygen |
|
|
Term
|
Definition
utilizes oxygen but can also grow in its absence |
|
|
Term
|
Definition
requires only a small amount of oxygen |
|
|
Term
|
Definition
|
|
Term
|
Definition
lacks the enzymes to detoxify oxygen so cannot survive in an oxygen environment |
|
|
Term
|
Definition
do not utilize oxygen but can survive and grow in its presence |
|
|
Term
|
Definition
grows best at higher CO2 tensions than normally present in the atmosphere |
|
|
Term
|
Definition
Majority of microorganisms grow at a pH between 6 and 8 |
|
|
Term
|
Definition
|
|
Term
|
Definition
grow at extreme alkaline pH |
|
|
Term
|
Definition
can survive under extreme pressure and willl rupture if exposed to normal atmospheric pressure |
|
|
Term
|
Definition
two organisms live together in a close partnership; mutualism, commensalism, parasitism |
|
|
Term
|
Definition
obligatory, dependent; both members benefit |
|
|
Term
|
Definition
commensal member benefits, other member neither harmed nor benefited |
|
|
Term
|
Definition
parasite is dependent and benefits; host is harmed |
|
|
Term
|
Definition
organisms are free-living; relationships not required for survival |
|
|
Term
|
Definition
members cooperate to produce a result that none of them could do alone |
|
|
Term
|
Definition
actions of one organism affect the success or survival of others in the same community (competition), antibiosis |
|
|
Term
Normal flora(microbes and humans) |
|
Definition
symbiotic bacteria, fungi, and a few protozoa |
|
|
Term
|
Definition
result when organisms attach to a substrate by some form of extracellular matrix that binds them together in complex organized layers; Dominate the structure of most natural environments on earth |
|
|
Term
|
Definition
Communicate and cooperate in the formation and function of biofilms |
|
|
Term
Microbial growthoccurs at two levels: |
|
Definition
growth at a cellular level with increase in size, and increase in population |
|
|
Term
Division of bacterial cells occurs mainly through: |
|
Definition
|
|
Term
|
Definition
Parent cell enlarges, duplicates its chromosome, and forms a central transverse septum dividing the cell into two daughter cells |
|
|
Term
Generation or doubling time: |
|
Definition
Time required for a complete fission, can vary from minutes to days |
|
|
Term
|
Definition
Each new fission cycle increases the population by a factor of 2 |
|
|
Term
|
Definition
In laboratory studies, populations typically display a predictable pattern over time |
|
|
Term
|
Definition
“flat” period of adjustment, enlargement; little growth |
|
|
Term
|
Definition
a period of maximum growth will continue as long as cells have adequate nutrients and a favorable environment |
|
|
Term
|
Definition
rate of cell growth equals rate of cell death caused by depleted nutrients and O2, excretion of organic acids and pollutants |
|
|
Term
|
Definition
As limiting factors intensify, cells die exponentially |
|
|
Term
|
Definition
method of analyzing population growth; most simple; degree of cloudiness, turbidity, reflects the relative population size |
|
|
Term
|
Definition
method of analyzing population growth; Viable colony count; Direct cell count – count all cells present; automated or manual |
|
|