Evolution of Bacteria Flashcards
Which type of bacteria stores energy from sunlight in the form of ATP?
Phototroph
Which type of bacteria gets energy from inorganic salts?
Chemolithotroph
Which type of bacteria gets energy from organic compounds like sugar, fats, proteins etc?
Chemoheterotroph
Which type of bacteria uses carbon dioxide as a source of carbon?
Autotroph
Which type of bacteria uses organic compounds as a source of carbon?
Heterotroph
Why do most bacteria not use carbohydrates as a source of energy/carbon?
They lack to required enzymes
Why might bacterial growth be limited by low levels of phosphate?
They lack the ability to synthesize it themselves
How do bacteria use sulfate/sulfide?
They convert it in to organic form for use in protein synthesis
Give 3 nitrogen containing substances which some bacteria can extract cellular materials from
Nitrates in soil
Dinitrogen gas
Ammonia
Why is the binding of iron particularly important for pathogenic bacteria?
They must compete with the host for iron
Bacteria secrete chemicals called _ , which tightly bind iron
Siderophores
The final acceptor in the electron transport chain for obligate aerobes is _
Oxygen
Which bacteria require oxygen in order to grow?
Obligate aerobes
Which bacteria have means of generating energy that are not coupled to oxygen consumption?
Obligate anerobes
What type of bacteria grows in the presence of low levels of oxygen?
Aerotolerant/microaerophilic
Which bacteria change metabolic processes depending on the presence/absence of oxygen?
Facultative anaerobes
Oxygen is very reactive and produces several toxic by-products. Name 3
Superoxide O2-
Hydrogen peroxide H2O2
Hydroxyl radical OH-
Which enzyme breaks down hydrogen peroxide?
Catalase
Which enzyme breaks down superoxide?
Superoxide dismutase
Why is oxygen poisonous to obligate anaerobes?
They do not produce the required amount of enzymes to detoxify the by-products of oxygen
What type of bacteria grows below 15 degrees celcius?
Psychrophilic
What type of bacteria has optimum growth between 20 and 45 degrees celcius?
Mesophilic
What type of bacteria grows in temperatures above 60 degrees celcius?
Thermophilic
What is the pH range that most bacteria grow within?
5 to 8
What type of bacteria can grow in pH of 10 to 11?
Alkalophilic
What type of bacteria prefers salty environments?
Halophiles
Extreme halophiles show optimum growth in conditions of _
20 to 30 percent salt
Moderate halophiles show optimum growth in conditions of _
5 to 20 percent salt
Which energy generating process takes place in the absence of an external electron acceptor?
Fermentation
The energy output of fermentation is _
Relatively low compared to respiration
The characteristic end products of different fermentation pathways _
Can aid in the identification of bacteria
Give 4 examples of inorganic compounds which can function as final electron acceptors in anaerobic respiration
Nitrate NO3-
Nitrite NO3-
Sulfate
Carbon Dioxide
