Microbiology for Optometry (BIMI200) Practice Flashcards

Comprehensive vocabulary flashcards covering the basics of microbiology, bacterial growth, control methods, and specific ocular infections like keratitis and conjunctivitis.

Bacteriology

The branch of microbiology specifically focused on the study of bacteria.

Mycology

The study of fungi.

Phytology

The study of algae.

Koch's Postulates

A set of four criteria proposed by Robert Koch to confirm that a specific microorganism is the causative agent of an infectious disease.

Prokaryotic Cells

Primitive, earliest forms of life ranging from $0.2 ext{-}2.0 ext{ μm}$ in diameter that lack a predefined nucleus and membrane-bound organelles.

Eukaryotic Cells

Complex organisms typically $10 ext{-}100 ext{ μm}$ in diameter containing true nuclei with linear DNA and membrane-bound organelles.

70S

The size classification of ribosomes found in prokaryotic cells.

Generation time ($G$)

The time required for an individual bacterial cell to undergo a division cycle and for the population to double.

Lag Phase

The initial period of the bacterial growth curve where individual cells increase in size but not in number as they adapt to their environment.

Stationary Phase

The growth phase where the rate of bacterial cell growth equals the rate of cell death.

Psychrophiles

Bacteria that grow optimally at cold temperatures between $0 ext{-}5^{ ext{ ∘}}C$.

Thermophiles

Microorganisms that grow optimally at or above temperatures of $55^{ ext{ ∘}}C$.

Autotrophs

Organisms that utilize inorganic nutrients or light as a source of energy.

Selective Medium

A bacterial growth medium designed to grow only certain types of microbes while inhibiting the growth of others.

MacConkey's (MAC)

A selective and differential medium that inhibits Gram(+) bacteria and uses neutral red to identify lactose fermenters by a pink color change.

Blood Agar (BAP)

A differential growth medium containing 5 ext{%} sheep blood used to distinguish bacteria by their ability to produce hemolysins.

Mannitol Salt (MSA)

A selective medium with 7.5 ext{%} $NaCl$ used to isolate Staphylococcus species and differentiate mannitol fermenters by a yellow color change.

Transcription

The process by which RNA polymerase creates a complementary RNA sequence from a DNA sequence.

Translation

The biological process in which an mRNA nucleotide sequence is converted into an amino acid sequence at the ribosome.

Sterilization

A microbial control process that destroys 100 ext{%} of microbes on non-living surfaces typically using steam under pressure or incineration.

Antisepsis

The reduction in the number of microorganisms, particularly potential pathogens, on living tissue.

Microbistatic agents

Agents that temporarily inhibit the reproduction of microbes but do not kill them.

Autoclaving

A physical control method using moist heat at $121^{ ext{ ∘}}C$ for $15 ext{ min}$ and pressure to achieve sterilization.

Antibiotics

Antimicrobial agents produced by microorganisms that kill or inhibit the growth of other microorganisms.

Plasmids

Transferable genetic elements that can transmit multiple resistance mechanisms to different types of antibiotics between bacteria.

Kirby-Bauer disc diffusion

A susceptibility test performed on an agar plate to determine if bacteria are susceptible or resistant to specific antibiotics.

Gram-positive bacteria

Bacteria with a cell wall consisting of many layers of peptidoglycan that remain violet or purple after Gram staining.

Gram-negative bacteria

Bacteria with a thin layer of peptidoglycan and an outer membrane of protein and fat that stain reddish pink.

Streptococci

Circular bacteria (cocci) arranged in chains.

Pleomorphic

A term describing bacteria that are genetically predisposed to have many shapes rather than just one.

Chitin

The primary substance found in the rigid cell walls of fungi.

Coccidioidomycosis

A fungal infection, also known as Valley Fever, caused by Coccidioides immitis through the inhalation of infectious arthrospores.

Ocular coccidioidomycosis

A rare secondary involvement of the eye following dissemination, most commonly affecting the eyelids, conjunctiva, and uvea.

Fungal keratitis

An infective process of the cornea caused by fungi like Fusarium or Aspergillus species, often occurring after trauma or in immunocompromised patients.

Acanthamoeba

A free-living amoebic protozoan found in water, soil, and dust that can cause serious ocular infections like keratitis.

Bacterial Keratitis

A rapidly progressive corneal infection that can cause complete corneal destruction within $24 ext{-}48 ext{ hours}$ by virulent bacteria.

Conjunctivitis

Inflammation of the conjunctiva, often called 'pink eye,' which can be viral, bacterial, or caused by allergens.

Acyclovir

A successful anti-viral agent that inhibits viral DNA and is used to treat Herpes zoster ophthalmicus (HZO) and speed resolution of HSV keratitis.

Adenovirus

The most common viral cause of conjunctivitis, typically leading to acute follicular reactions and preauricular adenopathy.

Innate immunity

Nonspecific defense mechanisms including physical barriers like the skin and blinking reflex that respond immediately to antigens.