BACTERIAL SURVIVAL Flashcards
- Which organisms can produce their own food from inorganic substances?
A) Heterotrophs
B) Autotrophs
C) Chemolithotrophs
D) Animals
B) Autotrophs
Rationale: Autotrophs are organisms that can produce their own food from the substances available in their surroundings without the need for organic nutrients.
- What do chemolithotrophs primarily use as their carbon source?
A) Oxygen
B) Methane
C) Organic matter
D) CO2
D) CO2
Rationale: Chemolithotrophs are a subset of autotrophs that use inorganic compounds for energy and utilize CO2 as their primary carbon source.
- Which element is a major component of proteins and nucleic acids?
A) Carbon
B) Oxygen
C) Nitrogen
D) Phosphorus
C) Nitrogen
Rationale: Nitrogen is an essential component of amino acids (building blocks of proteins) and nucleic acids (DNA and RNA).
- What is the end product of all pathways for nitrogen that most organisms can use?
A) N2
B) NO3
C) NH4
D) NH3
D) NH3
Rationale: Most organisms can utilize ammonia (NH3) as their nitrogen source.
- What form of nitrogen is most abundant in the Earth’s atmosphere?
A) N2
B) NO3
C) NH4
D) NH3
A) N2
Rationale: N2, or molecular nitrogen, makes up about 78% of the Earth’s atmosphere.
- Sulfur is an essential component of which molecules?
A) Carbohydrates
B) Amino acids
C) Fatty acids
D) Monosaccharides
B) Amino acids
Rationale: Sulfur is vital for the functioning of proteins and is an essential component of certain amino acids.
- Which molecule is crucial for storing and transferring energy within cells?
A) DNA
B) Glucose
C) ATP
D) RNA
C) ATP
Rationale: ATP (Adenosine Triphosphate) is essential for storing and transferring energy in cells.
- Phosphorus is a key component of which cellular structure?
A) Cell wall
B) Cytoplasm
C) Nucleus
D) Cell membrane
D) Cell membrane
Rationale: Phosphorus is a vital component of phospholipids that form cell membranes.
- In which form do organisms primarily uptake phosphorus from their environment?
A) Phosphoric acid
B) Phospholipids
C) Phosphate ions
D) Phosphorus gas
C) Phosphate ions
Rationale: Organisms uptake phosphorus in the form of phosphate ions (PO4^3-) from their environment.
- Which mineral is essential for enzymes involved in electron transfer?
A) Calcium
B) Magnesium
C) Iron
D) Potassium
C) Iron
Rationale: Iron is crucial for enzymes involved in electron transfer and oxygen transportation.
- Which organisms rely on organic carbon for their growth?
A) Autotrophs
B) Heterotrophs
C) Chemolithotrophs
D) Both A and C
B) Heterotrophs
Rationale: Heterotrophs are organisms that rely on organic carbon, taken from other living organisms, for their growth.
- Magnesium is primarily required for the activity of enzymes associated with which molecule?
A) DNA
B) Lipids
C) ATP
D) Carbohydrates
C) ATP
Rationale: Magnesium is essential for many enzymes, especially those involved in ATP metabolism.
- Which mineral is NOT crucial for enzyme activity?
A) Zinc
B) Iron
C) Magnesium
D) Helium
D) Helium
Rationale: Helium is a noble gas and is not known to be essential for any biological processes or enzyme activities in organisms.
- Which process involves the conversion of nitrogen into various forms usable by living organisms?
A) Photosynthesis
B) Carbon cycle
C) Nitrogen cycle
D) Oxygen cycle
C) Nitrogen cycle
Rationale: The nitrogen cycle consists of processes like nitrogen fixation, nitrification, and denitrification that help convert nitrogen into forms usable by living organisms.
- What do organisms that depend on plants primarily rely on for sulfur?
A) Proteins
B) Enzymes
C) Vitamins
D) All of the above
D) All of the above
Rationale: Sulfur is an essential component of certain amino acids, vitamins, and is vital for the functioning of proteins and enzymes in plants. Animals that depend on plants would consequently rely on these molecules for their sulfur.
- Which pH range is optimal for most organisms called Neutralophiles?
A) 3.0
B) 6.0 - 8.0
C) 10.5
D) 2-10
B) 6.0 - 8.0
Rationale: Neutralophiles primarily thrive in a pH range that is near neutral, which is 6.0 to 8.0.
- Acidophiles thrive in environments with a pH of?
A) 10.5
B) 5.0
C) 3.0
D) 6.5
C) 3.0
Rationale: Acidophiles prefer acidic environments, and they can thrive in conditions as low as pH 3.0.
- Which temperature range is suitable for Psychrophilic organisms?
A) 20 - 30° C
B) -5 - 15° C
C) 30° C
D) 37° C
B) -5 - 15° C
Rationale: Psychrophilic organisms prefer cold temperatures, and their range is -5 to 15° C.
- Mesophilic organisms have an optimal temperature of?
A) 30° C
B) -5° C
C) 20° C
D) 15° C
A) 30° C
Rationale: Mesophilic organisms have an optimal temperature around 30° C, which is suitable for many free-living forms.
- Which organisms require oxygen as a hydrogen acceptor?
A) Facultative Anaerobes
B) Obligate Aerobes
C) Obligate Anaerobes
D) Microaerophiles
B) Obligate Aerobes
Rationale: Obligate aerobes are organisms that strictly require oxygen as their hydrogen acceptor for energy production.
- Which of the following organisms require high salt concentrations?
A) Mesophiles
B) Psychrophiles
C) Halophilic
D) Osmophilic
C) Halophilic
Rationale: Halophilic organisms thrive in environments with high salt concentrations.
- Which organisms can live both aerobically and anaerobically?
A) Microaerophiles
B) Facultative Anaerobes
C) Obligate Aerobes
D) Aerotolerant Anaerobes
B) Facultative Anaerobes
Rationale: Facultative anaerobes have the capability to live and grow in both aerobic and anaerobic conditions.
- At which pH level do Alkaliphiles flourish?
A) 3.0
B) 6.5
C) 8.0
D) 10.5
D) 10.5
Rationale: Alkaliphiles are adapted to alkaline environments and can thrive at a pH as high as 10.5.
- Which organisms are indifferent to oxygen and do not use it as a hydrogen acceptor?
A) Microaerophiles
B) Obligate Aerobes
C) Aerotolerant Anaerobes
D) Facultative Anaerobes
C) Aerotolerant Anaerobes
Rationale: Aerotolerant anaerobes can grow in the presence of oxygen but do not use it as a hydrogen acceptor.