Bacterial DNA Organization and Plasmids

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What did Louis Pasteur's 'swan neck experiment' demonstrate?

Microorganisms do not just spontaneously arise. (correct)

Microorganisms can develop from nonliving or decomposing matter.

Microorganisms can only develop in the presence of foul air and bad smells.

Microorganisms are the result of the process of decay.

What did Joseph Lister innovate to prevent infections during surgery?

Introduction of techniques for study of microbial pathogens.

Use of foul air and bad smells to disinfect the surgical environment.

Application of miasma theory to cleanse the surgical tools.

Development of surgery methods to prevent infections. (correct)

What is the highest rank in microbial taxonomy?

Phylum

Order

Domain (correct)

Genus

How are gene names and protein names typically correlated in bacteria?

Both gene names and protein names consist of three lowercase letters followed by an uppercase fourth letter. Signup and view all the answers

What is the term for organisms that are variable in shape?

Pleomorphic Signup and view all the answers

What is the purpose of the 'swan neck' in Louis Pasteur's experiment?

To prevent microorganisms from developing in nutrient solutions placed in flasks. Signup and view all the answers

What is the function of external receptors on the cell surface in receptor-mediated endocytosis?

They specifically bind to macromolecules Signup and view all the answers

What is the main difference between bacterial and eukaryotic ribosomes?

Eukaryotic ribosomes have 60S + 40S subunits while bacterial ribosomes have 40S + 60S subunits Signup and view all the answers

What is the role of cilia and flagella in eukaryotic cells?

They are associated with motility Signup and view all the answers

What is a viroid composed of?

Nucleic acids (DNA/RNA) Signup and view all the answers

What do all virions contain?

Nucleic acid and a protein coat (capsid) Signup and view all the answers

What is the function of envelope proteins in viruses?

They are involved in viral attachment to host cells Signup and view all the answers

What type of transport uses ion gradients to cotransport substances?

Secondary active transport Signup and view all the answers

Which type of transport chemically modifies molecules as it is brought into the cell?

Group translocation Signup and view all the answers

What is the major component of the bacterial cell wall peptidoglycan?

Meshlike polymer of identical subunits forming long strands Signup and view all the answers

Which type of bacteria has a cell wall that consists primarily of peptidoglycan and may also contain teichoic acids?

Gram-positive Signup and view all the answers

What do Gram-negative cell walls consist of, in addition to a thin layer of peptidoglycan?

Lipids, lipoproteins, and lipopolysaccharide (LPS) Signup and view all the answers

What connects to peptidoglycan and lipids in the plasma membrane in Gram-positive cell walls?

Lipoteichoic acids (LTA) Signup and view all the answers

What are the two types of alternative sugars in the peptidoglycan structure?

N-acetylmuramic acid (NAM) and N-acetylglucosamine (NAG) Signup and view all the answers

What is very insoluble, making its uptake difficult for microorganisms?

(Fe3+) Signup and view all the answers

Which type of bacteria consists of a thin layer of peptidoglycan surrounded by an outer membrane composed of lipids, lipoproteins, and lipopolysaccharide (LPS)?

Gram-negative Signup and view all the answers

What do Gram-positive cell walls primarily consist of?

Peptidoglycan Signup and view all the answers

What is covalently linked to peptidoglycan in Gram-negative cell walls?

Cell wall proteins with the LPXTG protein sequence Signup and view all the answers

What are the two types based on gram stain?

Gram-positive and Gram-negative Signup and view all the answers

Which structure aids in the condensation of the nucleoid in bacteria?

Nucleoid associated proteins (NAPs) Signup and view all the answers

What is the main function of plasmids in bacteria?

Conjugation Signup and view all the answers

Which type of motility involves short, intermittent, jerky motions due to pili at the ends of the cell?

Twitching motility Signup and view all the answers

What is the purpose of bacterial endospore formation?

Environmental adaptation Signup and view all the answers

Which statement best describes the movement of a bacterium during chemotaxis?

With increased concentration of attractant, the frequency of counterclockwise (CCW) rotation decreases Signup and view all the answers

What is the role of nucleoid associated proteins (NAPs) in bacteria?

Folding and condensation of the nucleoid Signup and view all the answers

What is the main function of flagella in bacteria?

Motility and attachment to surfaces Signup and view all the answers

Which structure is required for conjugation in bacteria?

Pili Signup and view all the answers

What triggers the process of sporulation in bacteria?

Lack of nutrients Signup and view all the answers

What is the main feature that distinguishes Archaea from Bacteria and Eukarya?

Unique elements specific to Archaea Signup and view all the answers

What is a characteristic feature of spirochete motility in bacteria?

Periplasmic flagella inside outer membrane Signup and view all the answers

What is the smallest observed size for Archaeal rods?

0.2 μm in diameter Signup and view all the answers