bacteria and infections Flashcards
(18 cards)
What is the primary difference between prokaryotic and eukaryotic cells?
Prokaryotic cells (e.g., bacteria) are smaller (0.4–2.0 µm), lack organelles, and have a circular chromosome. Eukaryotic cells (e.g., animal and plant cells) are larger (5–100 µm), contain organelles, and have linear chromosomes.
What is the significance of peptidoglycan in bacterial classification?
Peptidoglycan is the major component of bacterial cell walls and is crucial for distinguishing gram-positive (thicker peptidoglycan) from gram-negative (thinner peptidoglycan) bacteria.
What are the main shapes of bacteria?
Cocci: Spherical-shaped.
Bacilli: Rod-shaped.
Spirals: Spiral-shaped.
Vibrio: Comma-shaped.
What are the two major bacterial categories based on gram staining?
Gram-positive: Bacteria with a thick peptidoglycan layer in the cell wall.
Gram-negative: Bacteria with a thinner peptidoglycan layer and an additional outer membrane.
What are the major components of a bacterial cell wall?
The cell wall includes peptidoglycan (for shape and protection), teichoic acids (in gram-positive bacteria), and lipopolysaccharides (LPS) (in gram-negative bacteria).
What are plasmids, and how do they contribute to bacterial function?
Plasmids are small, circular DNA molecules that carry non-essential genes (e.g., antibiotic resistance genes) and can be transferred between bacteria, contributing to genetic diversity and antibiotic resistance.
What is the role of flagella in bacteria?
Flagella are long, whip-like structures that provide motility to bacteria, allowing them to move toward or away from environmental stimuli (chemotaxis).
What is the function of pili (fimbriae) in bacterial cells?
Pili (fimbriae) help bacteria adhere to surfaces and host cells. Conjugation pili are involved in the transfer of genetic material (plasmids) between bacteria.
What is the process of synaptic pruning, and how can cannabis use disrupt it?
Synaptic pruning is the process where the brain removes unnecessary neural connections. Cannabis use during adolescence can disrupt this process, leading to cognitive and emotional issues, particularly in regions like the hippocampus and prefrontal cortex.
What is the role of lipopolysaccharides (LPS) in gram-negative bacteria?
LPS is an endotoxin found in the outer membrane of gram-negative bacteria. It can trigger immune responses and contribute to inflammation.
What is bacterial conjugation, and how does it relate to antibiotic resistance?
Bacterial conjugation is the transfer of genetic material (e.g., antibiotic resistance genes) between bacterial cells through pili, facilitating the spread of antibiotic resistance.
What is gram staining, and why is it important in identifying bacterial infections?
Gram staining is a laboratory technique that differentiates bacteria into gram-positive (purple) and gram-negative (pink) based on the structure of their cell wall. This helps determine appropriate treatment, including antibiotic choice.
What are the different classifications of bacterial infections in optometry?
Common bacterial infections in optometry include conjunctivitis, keratitis, and endophthalmitis, which may be caused by both gram-positive and gram-negative bacteria, such as Staphylococcus aureus, Pseudomonas aeruginosa, and Haemophilus influenzae.
What is nosocomial infection, and how does it impact ocular health?
Nosocomial infections are infections acquired in a healthcare setting, which may include post-surgical eye infections or infections in immunocompromised patients, requiring careful monitoring and infection control.
How does systemic disease contribute to ocular infections?
Systemic diseases like diabetes, HIV, and autoimmune diseases can compromise the immune system, increasing the risk of ocular infections such as conjunctivitis, keratitis, and endophthalmitis.
What is the role of antibiotic resistance in ocular infections?
Antibiotic resistance occurs when bacteria evolve to resist the effects of drugs used to treat infections. This can lead to treatment failure in conditions like bacterial keratitis and endophthalmitis, necessitating alternative or more potent treatments.
an example of positive chemotaxis
A bacteria cell being attracted to another bacterial cell
an example of ‘direct’ transmission of disease?
An individual coughing and covering their mouth, followed by
immediately shaking hands with a colleague
