CH1-S2 Flashcards
_____ is the study of the life processes of microoraganisms
Microbial physiology
The energy sources for certain organisms (called ___ ) is light and for other organisms (called ____ ) is organic or inorganic chemicals
phototrophs, chemotrophs
_____ need to acquire nutrients from other sources of organic carbon, mainly plant or animal matter
Heterotroph
____ refers to all of the _____ that occur within a living cell, including the production of energy and the synthesis of new molecules
Metabolism, chemical reactions
____ involve the breaking of chemical bonds and the release of energy
Catabolic reactions
____ require energy because they involve the formation of chemical bonds
Anabolic reactions
Most metabolic reactions are regulated by ____
enzymes
Enzymes are biologic molecules that serves as _____ to control the rate of metabolic reactions
catalysts
Describe 2 types of enzymes (bacteria will release)
Endoenzymes- ramain within the cells that produced them, Exoenzymes- enzymes that leave the cell to catalyze reactions outside of the cell
When will enzyme operate at peak efficiency?
It operate at peak efficiency within a particular pH and temperature range and when an appropriate concentration of the substrate for that enzyme exists
______ enzymes produces in constant amounts without regard to to physiological demand or the concentration of substitute
Constitutive
_____ enzymes requires or its stimulated by a specific small molecule
Induced
What is the common pathway by which bacteria catabolize glucose?
Aerobic respiration
____ must catabolize glucose by ______, a relatively inefficient method that yields only two ATP molecules from a molecule of glucose
Anaerobes, fermentation
Is oxygen participate in fermentation reactions?
No
List 5 factors that affect microbial growth
Availability of nutrients, moisture, temperature, pH, gaseous atmosphere
Describe one of the 5 factors that affect microbial growth-availability of nutrients
All living organisms require nutrients to sustain life
Describe one of the 5 factors that affect microbial growth-moisture
Microbes require water to dissolve enzymes and nutrients required in metabolism, certain microbial stages (e.g., bacteria endospores and protozoal cysts) can survive a drying process (desiccation)
Describe one of the 5 factors that affect microbial growth-temperature
Generally, Temperature increase will increase enzymatic activity; too high temperature denature protein, best growth between 25 to 40 degree Celsius, optimum temperature commonly 37 degree Celsius
Describe one of the 5 factors that affect microbial growth-pH
Most microorganisms prefer a neutral or slightly alkaline growth medium (pH 7.0 - 7.4)
Describe one of the 5 factors that affect microbial growth-Gaseous atmosphere
Aerobic bacteria require oxygen for growth, anaerobic bacteria dies in the presence of oxygen, and therefore avoids oxygen
_____ require oxygen for growth, e.g. most fungi, protozoa, and many bacteria, such as _____, and _____
Aerobes, Bacillus spp., Mycobacterium tuberculosis
_____ only anaerobic growth (avoid ______), e.g. many _____, _____ bacteria
Anaerobes, oxygen, oral, intestinal
______ - both aerobic and anaerobic growth; greater growth in ______ of oxygen, e.g. many gram _____ intestinal bacteria, ______
Facultative anaerobes, presence, negative, staphylococci
_____ - only _____ growth, but continues in _____ of oxygen, e.g. certain ________ and _________, clostridial spp.
Aerotolerant anaerobes, anaerobic, presence, lactobacili, streptococci
In a loose-fitting cap with a tube holding liquid, ____ go upward.
Obligate aerobes
In a loose-fitting cap with a tube holding liquid, _____ go downward.
Obligate anaerobes
In a loose-fitting cap with a tube holding liquid, most of the ____ go upward and some are in middle and bottom
Facultative anaerobes
In a loose-fitting cap with a tube holding liquid, _____ equally distributed.
Aerotolerant anaerobes
An organism’s _____ is its complete collection of genes, whereas an organism’s _____ is all the physical traits, attributes, or characteristics of the organism.
genotype, phenotype
What is genotype?
It is its complete collection of genes
What is phenotype?
It is all the physical traits, attributes, or characteristics of the organism.
Random mutations arise naturally during ____.
cell division
_____ are expressed not only in the cell in which the mutation occurred, but in subsequent generations as well.
Mutations
_____ are used in genetic and medical research and the production of vaccines.
Mutant bacteria
Mutations may be _____, _____, or of _____ to the cell or organism containing the mutation.
beneficial, harmful, no consequence
Some harmful mutations are _____ to the organism.
lethal
Physical or chemical agents that cause an increased mutation rate are called _____.
mutagens
What are the examples for physical agents?
Control temperature/ filtration/ desiccation
What are the examples for chemical agents?
Disinfectants/ antiseptics
_____, ___, ____, ____ or ____ may cause mutations and genetic changes in a bacterial cell.
Lysogenic conversion, transduction, transformation, conjugation
_____ is the process that ______, which are obligate intracellular virues that specifically infect _____; enter the host cell to reproduce
Lysogenic conversion, bacteriophage, bacteria
_____ is the process by which a virus transfers genetic material from one bacterium to another
Transduction
The process of transduction: _____ infect ________ and use them as hosts to make more viruses. After multiplying, these viruses assemble and occasionally remove a portion of the host cell’s bacterial DNA. When one of these bacterial DNA, this piece of _____ may be incorporated into the _____of the new host.
bacteriophages, bacterial cells, bacterial DNA, genome
_____ uptake of DNA fragments (“naked DNA”) from the environment.
Transformation
_____ involves the transfer of genetic material from a donor cell to a recipient cell through a hollow sex pilus.
Conjugation
_____ refers to the manufracture and manipulation of genetic material in vitro體外(in the laboratory)
Genetic engineering
When a molecule of _____ is inserted into a bacterial cell, the bacterium is able to produce the gene product, usually a protein.
recombinant DNA
An example of a product produced by genetic engineering is _____, a hormone produced in _____ cells and used to treat _____.
insulin, E. coli, diabetic
Give examples that are produced by genetically engineered E. coli.
Human growth hormone (somatotropin), tissue growth factors, clotting factors, interferon
