7.2 Bacterial Classification

Bacteria are classified into how many major groups based on genetic similarities? a) 2 b) 5 c) 8 d) 10

What is the main characteristic used to differentiate Gram-positive and Gram-negative bacteria? a) Cell size b) Flagella presence c) Cell wall structure d) Nucleus structure

Which bacterial group is known for its wavy, spiral structure? a) Proteobacteria b) Spirochetes c) Chlamydias d) Cyanobacteria

Cyanobacteria are often referred to as: a) Red algae b) Blue-green algae c) Brown algae d) Green algae

What is the primary characteristic that distinguishes Green Sulfur Bacteria? a) Aerobic phototrophy b) Production of oxygen during photosynthesis c) Utilization of sulfide or sulfur for photosynthesis d) Lack of chlorosomes in their cells

What is the primary function of the carboxysome in cyanobacteria? a) Photosynthesis b) Nitrogen fixation c) Carbon dioxide fixation d) Oxygen production

Which bacterial group includes species capable of causing diarrhea in humans? a) Alpha Proteobacteria b) Beta Proteobacteria c) Gamma Proteobacteria d) Delta Proteobacteria

Gram-positive bacteria have a cell wall composed mainly of: a) Peptidoglycan b) Lipopolysaccharides c) Cellulose d) Chitin

What is a unique characteristic of spirochetes? a) Flagella located outside the cellular body b) Lack of flagella c) Flagella located in the periplasm d) Flagella used for external fluid interaction

What is the smallest group of Proteobacteria? a) Alpha Proteobacteria b) Beta Proteobacteria c) Gamma Proteobacteria d) Epsilon Proteobacteria

What is the characteristic shape of bacteria that are classified as cocci? a) Rods b) Spirals c) Spheres d) Cubes

Which bacterial group is intracellular obligate parasites of animals and humans? a) Proteobacteria b) Chlamydias c) Spirochetes d) Cyanobacteria

Which bacterial group is characterized by the absence of nuclei and membrane-bound organelles? a) Archaea b) Eukaryotes c) Prokaryotes d) Viruses

What is the name of the unique cellular envelope found in thermophilic bacteria known as Thermotogae? a) Capsule b) Toga c) Coccus d) Peptidoglycan

Which bacterial group includes species that are often used as vectors in genetic engineering? a) Alpha Proteobacteria b) Beta Proteobacteria c) Gamma Proteobacteria d) Delta Proteobacteria

What bacterial group is widely studied for its potential use in biofuel production? a) Chlamydias b) Spirochetes c) Cyanobacteria d) Gram-positive bacteria

Which bacterial group is found in the gastrointestinal tract of humans and animals, forming mutualistic relationships with hosts? a) Bacteroidetes b) Thermotogae c) Green Sulfur Bacteria d) Green Non-Sulfur Bacteria

What is the primary pigment used by green sulfur bacteria for photosynthesis? a) Chlorophyll b) Bacteriochlorophyll c) Phycoerythrin d) Phycocyanin

Which bacterial group is characterized by its ability to fix nitrogen? a) Alpha Proteobacteria b) Beta Proteobacteria c) Gamma Proteobacteria d) Cyanobacteria

What is the function of the light-trapping organelles called chlorosomes in green sulfur bacteria? a) Oxygen production b) Carbon dioxide fixation c) Photosynthesis using sulfide or sulfur d) Locomotion

What is the function of the light-trapping organelles called chlorosomes in green sulfur bacteria? a) Oxygen production b) Carbon dioxide fixation c) Photosynthesis using sulfide or sulfur d) Locomotion

What is the main characteristic of green non-sulfur bacteria that distinguishes them from green sulfur bacteria? a) Type of electron acceptor used in photosynthesis b) Presence of flagella c) Gliding motion for locomotion d) Ability to produce oxygen during photosynthesis

Which bacterial group is known for its spiral or curve-shaped members that are pathogenic to animals and humans? a) Alpha Proteobacteria b) Beta Proteobacteria c) Gamma Proteobacteria d) Epsilon Proteobacteria

What is the primary structure of the cell wall in Gram-positive bacteria? a) Outer membrane b) Peptidoglycan layer c) Lipopolysaccharides d) Cellulose