microbe mission 2 Flashcards
What is the structure of bacteria?
Unicellular organisms with a simple structure.
What is the bacterial membrane composed of?
- Phospholipid bilayer
- Proteins
- Lipopolysaccharides (in gram-negative bacteria)
What is the function of the bacterial cell wall?
Provides structural support and protection, maintains cell shape, and prevents osmotic lysis.
What are bacterial flagella used for?
Enable bacterial motility through rotation.
What are bacterial pili (plus) used for?
- Genetic material transfer (conjugation)
- Attachment to surfaces or each other
What are bacterial fimbriae?
Short hair-like structures used to attach to surfaces or host tissues.
What is the bacterial nucleoid?
Region within cytoplasm containing DNA.
What is the bacterial cytoplasm composed of?
- Water
- Enzymes
- Ions
- Small molecules
- Ribosomes
What are bacterial gas vesicles used for?
Provide buoyancy to allow aquatic bacteria to float at specific depths.
What are endospores?
Highly resistant, dormant forms of bacteria encased in a tough coat.
What are archaea?
Microorganisms similar to bacteria but capable of surviving in extreme environments.
What is unique about the archaeal cell membrane?
Contains ether linkages and can be lipid monolayers or bilayers.
What is the archaeal cell wall composed of?
- Pseudopeptidoglycan
- Polysaccharides
- Proteins
What are eukaryotic cells characterized by?
More complex structure with membrane-bound organelles.
What is the eukaryotic cell membrane composed of?
- Lipid bilayer
- Embedded proteins
- Cholesterol
What are the organelles of the eukaryotic cell?
- Mitochondria
- Endoplasmic reticulum
- Golgi apparatus
- Lysosomes
What is the function of contractile vacuoles?
Maintain osmotic balance in some protists.
What are eyespots used for in some protists?
Detect light to help the organism orient itself.
What are carboxysomes?
Protein shells containing enzymes for carbon fixation.
What is the structure of gram-positive bacteria?
Thick peptidoglycan layer with teichoic acids, no outer membrane.
How do gram-negative bacteria differ from gram-positive bacteria?
Thin peptidoglycan layer with an outer membrane made of lipopolysaccharides.
What characterizes acid-fast bacteria?
Cell wall made of mycolic acids, appears red/pink after staining.
What is the gram stain procedure?
Distinguishes between gram-positive and gram-negative bacteria.
What is a virus?
Unique microorganisms capable of infecting host organisms.