Unit 2 Test Review

What is a pathogen?

A disease-causing microorganism.

What are macrophages/monocytes?

White blood cells that engulf and digest pathogens.

What are neutrophils?

White blood cells that are the most abundant and also engulf and digest pathogens.

What do eosinophils target?

Parasites and are involved in allergic reactions.

What are lymphocytes involved in?

Adaptive immunity, including T cells and B cells.

What is the innate immune system?

Non-specific defenses present at birth; rapid response.

What is the adaptive immune system?

Specific defenses that develop over time; slower response; immunological memory.

What defines eukaryotic cells?

Cells with a nucleus and membrane-bound organelles.

What defines prokaryotic cells?

Cells lacking a nucleus and membrane-bound organelles.

What types of organisms are fungi, plants, and animals?

Eukaryotic organisms.

What defines bacteria?

Prokaryotic organisms.

What is binary fission?

Replication of a cell to create 2 clone cells.

What is gene expression?

Process by which genetic information is used to synthesize proteins.

What is transcription?

Copying DNA code into mRNA.

What is translation?

Reading mRNA code and making a specific protein.

What makes up bacterial cell walls?

Peptidoglycan.

What is Gram-positive (G+)?

Thick peptidoglycan layer; stains purple.

What is Gram-negative (G-)?

Thin peptidoglycan layer and lipopolysaccharide layer; stains pink.

What does LPS stand for?

Lipopolysaccharide; outermost layer of cell wall in G- bacteria; contains Lipid A (endotoxin).

What are flagella?

Appendage used for motility.

What are the shapes of bacterial cells?

Coccus (spherical), Bacillus (rod-shaped), Spirilla (spiral-shaped).

What is a bacterial endospore?

Dormant, resistant stage that some bacteria can produce to survive harsh conditions.

What is the difference between a bacterial endospore and a bacterial cell?

An endospore cannot feed, grow, or reproduce; it is a survival form.

What disease does Bacillus anthracis cause?

Anthrax.

What is phagocytosis?

Ingestion of bacteria or other material by phagocytes.

Which white blood cells guard the alveoli in the lower respiratory system?

Macrophages located in the lower respiratory system.

What is a nosocomial infection?

Hospital acquired infection.

Who are at the highest risk for a C. diff infection?

Patients taking antibiotics, immunocompromised individuals, those with long hospital stays.

What role do antibiotics play in a C. diff infection?

Antibiotics can suppress beneficial bacteria, allowing C. diff to thrive.

What is the route of transmission for C. diff?

Fecal-oral route.

What is the treatment for recurrent (3 or more) C. diff infections?

Fecal microbiota transplantation (FMT).

Can C. diff form a bacterial endospore? Why does this make it more dangerous?

Yes, it allows it to survive for extended periods and resist sterilization methods.

Which antibiotic increases the chance a patient will develop a C. diff infection?

Clindamycin.

What are archaea?

Prokaryotic; not typically pathogenic.

What is a biofilm?

Bacterial communities on surfaces; protected by a matrix.

What are nosocomial infections?

Infections acquired in a hospital or clinical setting.

What is a nucleus?

Enclosed in a double membrane; contains genetic material (DNA).

What do mitochondria do?

Generate chemical energy (ATP) by cellular respiration.

What is the function of a lysosome?

Contains digestive enzymes for breaking down materials.

Do all eukaryotic cells have a cell wall?

No.

Do plant cells have a cell wall?

Yes.

Do animal cells have a cell wall?

No.

Do fungal cells have a cell wall?

Yes.

What is an eukaryotic cell wall composed of?

Composed of polysaccharide (chitin, cellulose).

What is taxonomy?

Formal system for classifying, identifying, and naming organisms.

How must the scientific name of an organism be written?

Italics; underlined.

What is the smallest group in taxonomy?

Species.

What is the largest group in taxonomy?

Domain.

Are yeast prokaryotes or eukaryotes? Are they single-celled or multicelled?

Eukaryotes; single-celled.

What does acellular mean?

Not made up of cells; lack cytoplasm and metabolism.

What type of microscope is used to view viruses?

Electron Microscope.

What are anabolic reactions?

Reactions that build/make other molecules/compounds; requires energy.

What are catabolic reactions?

Reactions that decompose or break down molecules/compounds; releases energy.

What is metabolism?

All the chemical reactions in an organism.

What are enzymes?

Protein catalysts that carry out chemical reactions.

What is cellular respiration?

How cells make ATP.

Does aerobic respiration require oxygen?

Yes.

How much ATP does aerobic respiration generate?

36-40 ATP.

Does anaerobic respiration require oxygen?

No.

How much ATP does anaerobic respiration generate?

2 ATP.

What are the products of photosynthesis?

Glucose and oxygen.

What is ATP?

Adenosine Triphosphate; energy currency of the cell.

What is DNA polymerase?

Enzyme that forms the DNA polymer.

What are autotrophs?

Organisms that make their own food.

What are heterotrophs?

Organisms that must eat other living things for carbon and energy.

What is an obligate aerobe?

Must have O2 at normal atmospheric levels (20%).

What is an obligate anaerobe?

Cannot live in the presence of O2.

What is a facultative anaerobe?

Can live in the presence or absence of O2.

What are halophiles?

Require high salt concentrations.

What are thermophiles?

Like it hot.

What is Listeria monocytogenes?

Gram + bacillus, facultative anaerobe.

What are the 2 main forms of infection caused by Listeria?

Gastroenteritis: infection of the GI tract; disseminated Listeriosis: spread to other organs.

What is meningitis?

Inflammation of the protective membranes covering the brain and spinal cord.

What is a transplacental infection?

Infection transmitted across the placenta.

What are methods of diagnosis for infections?

Stool culture, serologic testing, cerebrospinal fluid, amniotic fluid, CT scan.

Who is at higher risk for listeriosis?

Newborns, pregnant women, 65+.

How do low temperatures or freezing affect Listeria monocytogenes?

Survives and can grow under refrigeration; freezing will not eliminate it.

What is an acidophile?

An organism that thrives in low pH environments.

What is an alkalinophile?

An organism that thrives in high pH environments.

What does microbial growth refer to?

Increase in population due to reproduction (binary fission).

What are the 4 phases of log growth?

Lag phase, Log phase, Stationary phase, Death phase.

What do βeta-lactam antibiotics target?

Cell wall of bacterial cells.

What is the effect of βeta-lactam antibiotics on bacteria?

They destroy bacterial cell walls.