Bacterial Structure and Plasmids Quiz

<p>Reductase (B)</p> Signup and view all the answers

<p>Movement within host cells (C), Coding for metabolic enzymes (D)</p> Signup and view all the answers

<p>Capsule (B)</p> Signup and view all the answers

<p>Adherence to epithelial cells (D)</p> Signup and view all the answers

<p>1–3 (A)</p> Signup and view all the answers

<p>Cocci, bacilli, and spirochetes (C)</p> Signup and view all the answers

<p>Cell wall (C)</p> Signup and view all the answers

<p>Peptidoglycan (D)</p> Signup and view all the answers

<p>Gram-positive bacteria (B)</p> Signup and view all the answers

<p>Capsule (B)</p> Signup and view all the answers

<p>Spirochetes (C)</p> Signup and view all the answers

<p>Structural support (B)</p> Signup and view all the answers

<p>Variable in shape like pleomorphic bacteria (D)</p> Signup and view all the answers

<p>Serve as the origin of the transverse septum (B)</p> Signup and view all the answers

<p>70S with 50S and 30S subunits (A)</p> Signup and view all the answers

<p>Bacterial DNA is circular. (C)</p> Signup and view all the answers

<p>It contains DNA without histones. (D)</p> Signup and view all the answers

<p>They replicate independently of the bacterial chromosome. (D)</p> Signup and view all the answers

<p>It has two distinct areas including the nucleoid. (D)</p> Signup and view all the answers

<p>They serve as storage areas for nutrients. (A)</p> Signup and view all the answers

<p>They target the smaller size and composition differences of bacterial ribosomes. (A)</p> Signup and view all the answers

<p>To facilitate the binding of transpeptidases during peptidoglycan synthesis (D)</p> Signup and view all the answers

<p>It irreversibly binds to its active site, inhibiting function (C)</p> Signup and view all the answers

<p>They can induce septic shock similar to endotoxins (C)</p> Signup and view all the answers

<p>Lipopolysaccharide (LPS) (C)</p> Signup and view all the answers

<p>They trigger inflammatory responses leading to fever and shock (A)</p> Signup and view all the answers

<p>Exotoxins are usually proteins, whereas endotoxins are lipopolysaccharides (B)</p> Signup and view all the answers

<p>Polymers of glycerol phosphate or ribitol phosphate (D)</p> Signup and view all the answers

<p>They prevent transpeptidase from binding to D-alanine (C)</p> Signup and view all the answers

<p>They mediate the attachment of bacteria to specific receptors on human cells. (A)</p> Signup and view all the answers

<p>Neisseria gonorrhoeae (A)</p> Signup and view all the answers

<p>To enable bacteria to adhere firmly to surfaces. (C)</p> Signup and view all the answers

<p>Endospores (B)</p> Signup and view all the answers

<p>Bacillus and Clostridium (D)</p> Signup and view all the answers

<p>Bacterial DNA, peptidoglycan, and a thick coat (A)</p> Signup and view all the answers

<p>Streptococcus mutans (B)</p> Signup and view all the answers

<p>It forms the attachment during bacterial conjugation. (B)</p> Signup and view all the answers

<p>Polysaccharide (A)</p> Signup and view all the answers

<p>84 (A)</p> Signup and view all the answers

<p>Limits phagocyte engulfment (D)</p> Signup and view all the answers

<p>To identify bacterial capsules (A)</p> Signup and view all the answers

<p>Long, whiplike appendages (D)</p> Signup and view all the answers

<p>Rods (C)</p> Signup and view all the answers

<p>Chemotaxis (A)</p> Signup and view all the answers

<p>By propelling bacteria into host tissues (B)</p> Signup and view all the answers

The outermost layer of bacterial cells that is composed of peptidoglycan and provides structural support, maintaining the characteristic shape of the cell.

A unique molecule found only in bacterial cell walls, composed of glycan chains linked by peptide bonds, providing rigidity and shape maintenance.

Gram-positive bacteria have a thick layer of peptidoglycan, making them stain purple in Gram staining. Gram-negative bacteria have a thin layer of peptidoglycan and an outer membrane, making them stain pink.

The outermost layer of Gram-negative bacteria, composed of phospholipids and lipopolysaccharide, providing an additional barrier and protection.

The innermost layer of the bacterial cell that encloses the cytoplasm. It is involved in various cellular processes, including energy production and transport.

Round-shaped bacteria.

Rod-shaped bacteria.

Spiral-shaped bacteria.

Large plasmids that contain genes for transferring themselves between bacteria. They are responsible for the synthesis of the sex pilus and enzymes required for transfer.

Small plasmids that lack the genes for transfer, meaning they cannot move between cells. They are often present in multiple copies within a single bacterial cell.

Specific genes carried by plasmids that provide immunity to specific antibiotics. These genes encode for enzymes that neutralize or inactivate the antibiotic.

Genes found on plasmids that confer resistance to heavy metals like mercury and silver. Usually encode for enzymes that remove or reduce the heavy metals inside the bacteria.

Genes carried by plasmids that allow the bacteria to survive exposure to ultraviolet (UV) light. These genes produce DNA repair enzymes.

Genes found on plasmids that code for pili (fimbriae), hair-like structures that extend outward from the bacterial cell and allow them to attach to cell surfaces. These pili play a crucial role in bacterial infections.

Genes carried by plasmids that produce exotoxins, including enterotoxins which cause intestinal discomfort and illness.

Pieces of DNA that can move freely within and between bacterial genomes, plasmids, and bacteriophages. These 'jumping genes' can carry genes for antibiotic resistance, toxins, and metabolic enzymes.

Enzymes that catalyze the formation of peptide cross-links in peptidoglycan, essential for bacterial cell wall synthesis.

A class of enzymes that break down peptide bonds within a protein chain.

Penicillin-binding proteins (PBPs) are essential bacterial enzymes involved in peptidoglycan synthesis. They are the primary targets for beta-lactam antibiotics like penicillin.

Beta-lactam antibiotics like penicillin bind to and inhibit the active site of transpeptidases, blocking the formation of peptide cross-links in peptidoglycan. This disrupts bacterial cell wall synthesis, leading to cell death.

Teichoic acids are polymers found in the cell walls of gram-positive bacteria, contributing to their structural integrity and mediating attachment to host cells. They can also trigger immune responses.

Lipopolysaccharide (LPS) is a major component of the outer membrane of gram-negative bacteria. It acts as an endotoxin, triggering immune responses and contributing to disease pathogenesis.

Endotoxins are toxins that are an integral part of the bacterial cell wall, unlike exotoxins, which are secreted.

The outer membrane of gram-negative bacteria is composed of a phospholipid bilayer containing lipopolysaccharide (LPS), which contributes to its structural integrity and plays a crucial role in immune responses.

The outermost layer of a bacterial cell, composed of polysaccharides, that protects the cell from its environment.

A reaction that occurs when a bacterium's capsule swells in the presence of specific antibodies. This reaction is used for identifying bacteria.

Long, whip-like structures that allow bacteria to move towards nutrients and other attractive substances.

The process by which bacteria move in response to chemical signals, such as nutrients or toxins.

The movement of bacteria using a flagellum-like structure called the axial filament, which wraps around the cell causing a wave-like motion.

A type of antigen found on some bacteria that is used to identify them.

The ability of a bacterium to cause disease, which is often influenced by the presence of a capsule that helps it evade the immune system.

Capsular polysaccharides can be used to make vaccines against certain bacterial diseases.

An invagination of the cytoplasmic membrane that plays a role in cell division by forming the transverse septum and serving as a binding site for DNA.

The gel-like substance within the cell, containing ribosomes, nutrients, metabolites, and plasmids. It also houses the nucleoid region, the DNA-containing area.

Small structures responsible for protein synthesis. Bacterial ribosomes are 70S, with 50S and 30S subunits, compared to eukaryotic ribosomes which are 80S.

The differences in ribosomal RNAs and proteins allow certain antibiotics to specifically inhibit bacterial protein synthesis, leaving human cells unaffected.

Storage areas for nutrients within the cytoplasm, often staining differently with specific dyes.

The region in the cytoplasm where DNA is located. It lacks a nuclear membrane, a nucleolus, and histones, making it different from a eukaryotic nucleus.

Extrachromosomal, circular DNA molecules that replicate independently of the bacterial chromosome. They can integrate into the chromosome and exist in both Gram-positive and Gram-negative bacteria.

Bacteria have a single, circular DNA molecule with approximately 2000 genes, whereas human DNA has around 100,000 genes.

Hair-like filaments extending from the bacterial cell surface, shorter and straighter than flagella, mainly found in gram-negative bacteria. Key roles include mediating bacterial attachment to specific receptors on human cells and forming the connection between donor and recipient bacteria during conjugation.

A polysaccharide coating secreted by many bacteria. It acts like a film, helping bacteria adhere to various surfaces like skin, heart valves, and catheters. It's crucial for some bacteria, like Streptococcus mutans, to stick to teeth, contributing to plaque formation.

Highly resistant structures formed inside certain bacteria (Bacillus and Clostridium) in response to harsh conditions. They contain bacterial DNA, a small amount of cytoplasm, and a thick, keratin-like coat, allowing survival in extreme environments.

A specialized pilus involved in bacterial conjugation, forming the connection between the donor and recipient bacteria during the transfer of genetic material.

A type of bacterial movement that involves the rotation of flagella, allowing the bacteria to move towards or away from stimuli like food or toxins.

A specialized pilus that allows bacteria to adhere to surfaces, crucial for colonization and infection. It's a major factor in bacterial pathogenicity.

The process of spore formation in bacteria, triggered by adverse conditions like nutrient depletion. It involves the encapsulation of genetic material and essential components within a resistant spore.

A type of bacterial motility where bacteria move across surfaces by extending and retracting pili. It's different from flagellar motility and often involved in surface colonization and biofilm formation.