test 1 Flashcards
benefits of microorganisms:
microorganisms are ? organisms that require a ? to be seen
average size of microbes is ? micrometer
nitrogen fixation, gut health, nutrient recycling, decomposition, antibiotic production, vaccine development, fermentation, gene therapy (genetic engineering)
living, microscope
1
?, such as bacteria and archaea, are generally smaller (0.1–5 µm) and ? a membrane-bound nucleus, with their genetic material located in a nucleoid region. They also lack most membrane-bound ?. Prokaryotic DNA is typically circular and exists as a single chromosome. they are also ?-celled.
prokaryotes, lack, organelles, single
?, such as fungi and protists, are larger (10-100 μm) & have a ?-? nucleus containing their DNA, and various other membrane-bound organelles within its cytoplasm. these cells also have DNA & ?. they are also ?-cellular and single-celled.
eukaryotes, membrane-bound, RNA, multi
how do you correctly write a scientific name?
if typing use italics; if handwriting underline
name some common tools used in gene therapy:
PCR, CRISPR, viral vectors
what kind of microbes would you expect to find in a human GI tract?
E. coli, lactobacillus, clostridium
difference between antiviral and antibiotic:
fun fact: Antibiotics do not work on viruses, which is why they aren’t used for viral infections like the flu or colds.
Antivirals target viruses by blocking viral entry, replication, or release. They do not kill the virus directly but slow its spread.
Antibiotics target bacteria, either by killing them or inhibiting their growth. They work by disrupting bacterial cell walls, protein synthesis, or DNA replication.
who invented the first microscope?
Antonie van Leeuwenhoek
what did robert hooke see in his microscope?
what is he credited with naming?
nematodes, mites, and mold filaments, cells
why was there a long period of time between the invention of the microscope and the use of it in the medical field?
it was due to poor quality of early microscope lenses causing significant image distortion and color aberrations, making it difficult to identify and observe microbes, also combined with a lack of understanding of the behaviors of certain microbes.
John Tyndall (an Irish scientist) stated that repeated cycles of ? are needed to ? material and eliminate ?.
heat, sterilize, endospores
The ?-? experiment simulated early Earth conditions by combining ?, methane, ?, and water vapor, then applying an electrical discharge to mimic lightning. This resulted in the formation of organic compounds, including amino acids, suggesting that life’s building blocks could form ? under those conditions.
Miller-Urey, hydrogen, ammonia, abiotically
what was the first vaccine designed to prevent?
smallpox
what does attenuated mean? a ? form of a ? used in vaccines to provoke ?
weakened, pathogen, immunity
what’s the largest source of natural source of antibiotics we have?
Actinomycetes
A ? is an organism that gains energy by ? inorganic compounds instead of organic matter.
lithotroph, oxidizing
benefits of the bubonic plague:
higher wages, vaccines, epidemiology, understanding of disease transmission, public health and hygiene
the purpose of ? culture is to significantly increase the # of the target microorganism by ? it and cultivating the proper environment for it to flourish, therefore ? the number & production of that target microorganism and making it easier to ?, ? and isolate.
enrichment, isolating, increasing, identify, study
The ? ? states that eukaryotic (plant/animal cells) cells engulfed prokaryotic cells and, instead of digesting them, they formed a ? relationship. Over time, the engulfed prokaryotes evolved into ? (in animal and plant cells) and chloroplasts (in plant cells), both of which have their own DNA and perform essential functions like energy production and photosynthesis.
endosymbiotic theory, mutualistic, mitochondria
the X-ray crystallography pattern of DNA was obtained by ? ?; it is known as the photo ?; this picture shows the double ? structure of DNA
Rosalind Franklin, 51, helical
The first cellular genome is sequenced: Haemophilus influenzae, a ?.
bacteria
In 2000, on a farm in
North Dakota, 67-year-old
Caleb helped bury 5 cows
that had died of ?.
Wearing heavy leather gloves, Caleb placed chains around the heads and hooves of the carcasses and moved them to the burial site. Four days later, he noticed a small lump on his left cheek. Over two days, the lump enlarged and a lesion opened.
Caleb sought medical attention. The physician reported a firm, superficial nodule surrounded by a purple ring, with an overlying black ? (piece of dead tissue sloughed from the skin).
The physician prescribed
?, the
standard antibiotic for
? anthrax.
anthrax, eschar, ciprofloxacin, cutaneous
name the 3 types of symbiotic relationships:
mutualism (both benefit), commensalism (one benefits while other is unaffected), parasitism (one benefits while other is harmed)
a sign is anything that can be ? or ?
a symptom is anything that can be ? or ?
measured or observed (seen)
felt or reported (felt)
what is an LD50 test?
a test that measures the exact amount of a substance that can be given to cause death in 50% of the test population
A ? is an organism that ? pathogens from one host to another.
vector, transmits
endemic is a disease that…
epidemic is a disease that…
Endemic: A disease that is consistently present in a specific area or population (e.g., malaria in parts of Africa).
Epidemic: A disease that spreads rapidly and affects many people in a short time (e.g., flu outbreak in a city).
Invasive disease: A disease caused by pathogens that ? and ? throughout the body, often affecting internal tissues (e.g., bacterial pneumonia).
? disease: A disease that is new or increasing in frequency in a population (e.g., COVID-19).
? disease: comes back after a while.
enter, spread, emerging, reemerging
say you have an epidemic, what is one/a few factor that can turn that epidemic into a pandemic?
Increased human mobility (e.g., air travel)
Mutations in the pathogen making it easily transmissible.
Lack of immunity allowing the disease to spread unchecked.
Inadequate public health response
Close contact in crowded areas
Climate change
Deforestation and habitat destruction: Can bring humans into closer contact with animals that may harbor new diseases.
Antibiotic resistance
Cultural or societal behaviors: Practices like mass gatherings or lack of sanitation could amplify transmission.
Asymptomatic carriers: People who don’t show symptoms but still spread the disease, making it harder to control.
Inconsistent reporting: Delayed or inaccurate reporting can hinder timely responses and containment efforts.
STOP THE SPREAD:
Urogenital (e.g., sexually transmitted infections):
use ?, get regular ?, ? or mutual monogamy
Parenteral (e.g., bloodborne diseases):
safe handling and ? of needles, ? needles, blood screening and ? testing.
Oral (e.g., foodborne or waterborne diseases)
proper ? hygiene and food safety, safe water and ?
Mosquito Vector (e.g., malaria, dengue)
mosquito ?, and protective clothing, Eliminate mosquito breeding sites (standing water), and ?
condoms, screenings, abstinence, disposing, sterile, donor, hand, sanitation, repellant, vaccination
The most common portal of entry for pathogens in the human body is the ? ?.
respiratory tract
Biosafety level ? organisms have little to no ? potential and require the ? level of containment. Standard sterile techniques and laboratory practices are sufficient.
1, pathogenic, lowest
Biosafety level ? agents have greater pathogenic potential, but ? and/or therapeutic treatments (for example, antibiotics) are readily available. this levels agents require somewhat rigorous ? procedures, such as limiting laboratory access when experiments are in progress.
2, vaccines, containment
Biosafety level ? pathogens produce a serious or ? human disease, but vaccines or therapeutic agents may be available. these room use ? pressure to ensure that ventilation air only flows into the room and exhaust air vents directly to the outside.agents may cause disease by ?.
3, lethal, negative, inhalation
Biosafety level ? examines highly dangerous and exotic pathogens with high risk of ? transmission. in this level full-body ?-pressure suits are used and the lab is completely isolated.
4, aerosol, positive
what are the risk factors working as a healthcare worker in the hospital?
Direct patient contact
Bloodborne pathogens
Needle stick injuries
Respiratory exposure
Inadequate personal protective equipment (PPE)
Hospital-acquired infections (HAIs)
Physical and mental stress
Improper hand hygiene
? host range: A pathogen that can infect a variety of different species.
? host range: A pathogen that infects only specific species or sometimes a specific tissue within a host.
broad, narrow
As global warming progresses, warmer temperatures allow disease ? to thrive in new areas, spreading illnesses like malaria and dengue. Longer warm seasons can extend the time during which diseases are transmitted, such as flu or waterborne infections. Additionally, extreme weather events like floods and hurricanes can ? water supplies and ? the spread of diseases like cholera. Increased heat and humidity also create favorable conditions for ? and fungi to grow, leading to higher rates of infections like fungal diseases and gastrointestinal illnesses. As ecosystems shift due to climate change, animals and pathogens may come into closer ? with humans, raising the risk of zoonotic diseases like Zika virus or Ebola.
vectors, contaminate, increase, bacteria, contact
? ? is the process by which a pathogen is passed from a mother to her fetus through the placenta
transplacental transmission
In 1884, Yong Ding was a 38-year-old male who worked as a cook in Canton, located in southern China. Life was hard, but he still managed to support his family. As he walked to his restaurant each day, he barely noticed the small bands of rats scurrying through the streets. Disease was rampant that year; victims of the Shuyi (rat epidemic) were stacked like firewood in the streets, five bodies high in places, waiting to be taken for burial. Yong Ding knew that the disease started as a ? gland in the armpit (?) that often had a ? appearance (now called a ?). He checked himself daily for these swellings and, seeing none, always felt relief. Then, one morning, he found one. Within days, Yong Ding began coughing ? as the agent (a mystery at the time) spread though his bloodstream to his ?. Once that happened, he knew death was not far behind. Within weeks, more than 60,000 people died this way in Canton—victims of what would be called the Third Pandemic of bubonic plague. Yong Ding’s body was one of many lining the streets that year.
swollen, axillary, black, bubo, blood, lungs
parts of compound microscope:
condenser: ? light to improve image ?
diaphragm: controls ? of light passing thru
parfocal occurs when the microscope stays in ? when ? ?
total magnification = mag of ? times mag of ? ?
depth of field refers to the ? of the area in focus
wet mount is used to view ? microbes by using ? to keep it hydrated while studying the specimen
focuses, clarity, amount, focus, switching lenses
eyepiece, objective lens
thickness
living, water
PATHWAY OF LIGHT THRU MICROSCOPE:
light can shine on brilliant eyes
light source -> condenser -> specimen -> objective lens -> body tube -> eyepiece -> eye
total mag =
current magnification time 10x
?-field – Standard, uses light for bright backgrounds and stained specimens.
?-field – Special lighting, dark background, great for unstained, living specimens.
Electron (SEM & TEM) – High magnification, ? for surfaces, ? for internal structures.
Scanning Electron Microscope (SEM) – ? images of surfaces.
Phase-contrast – Enhances ? details of transparent, living cells.
Fluorescence – ? specific structures using fluorescent light.
? – Uses X-rays for imaging ? or thick specimens like bones.
baright, dark, SEM, TEM, 3D, internal, highlights, X-ray, dense
??? invented the gram stain
Hans Christian Gram
The purpose of the Gram stain is to classify ? into two groups, Gram-positive and Gram-negative, based on the structure of their cell ?. This helps in identifying bacterial species and guiding the choice of ? for treatment. The stain uses crystal ? dye, iodine, alcohol, and ? to differentiate bacteria based on their cell wall’s ability to ? the dye.
bacteria, walls, antibiotics, violet, safranin, retain
Gram-? bacteria are characterized by a ? peptidoglycan layer in their cell wall, which allows them to ? the crystal violet stain during the Gram staining process, making them appear purple under a microscope. they lack an outer ? membrane which makes their cell walls more rigid and vulnerable to certain ? that target cell wall synthesis. These structural features contribute to their overall susceptibility to different antimicrobial treatments.
positive, thick, retain, lipid, antibiotics
Gram-negative bacteria have a ? peptidoglycan layer in their cell wall, which (does/does not retain) the crystal violet stain during the Gram staining process. As a result, they appear ? or ? under the microscope after the procedure. They ? an outer lipid membrane, which makes them more resistant to certain antibiotics, as the membrane acts as a ? to drug penetration. The outer membrane also contains lipopolysaccharides, which contribute to the bacteria’s ability to cause inflammation and can serve as endotoxins. These structural differences make Gram-negative bacteria more resilient to some environmental factors and antibiotics compared to Gram-positive bacteria.
thin, does not retain, pink, red, possess, barrier
The chemicals used in the Gram staining procedure are:
? ?: A primary stain that stains all bacterial cells purple.
?: A mordant that forms a complex with crystal violet, helping it bind more tightly to the bacterial cell walls.
Alcohol (or Acetone/?): The decolorizer, which washes away the crystal violet-iodine complex from Gram-negative bacteria due to their thin peptidoglycan layer, while Gram-positive bacteria retain the dye.
?: A counterstain that stains the decolorized Gram-negative bacteria pink or red, allowing them to be visible under the microscope.
crystal violet, iodine, ethanol, safranin
A Congo red stain is primarily used in pathology to identify the presence of ? deposits in ? samples
amyloid, tissue
Malachite green stain is primarily used in microbiology to specifically identify and visualize ? ? within a sample
bacterial endospores
? blue stain is primarily used in microbiology to color and highlight specific structures within cells, like nuclei and bacteria, allowing researchers to easily observe their shapes, locations, and morphology
Methylene
A ? field microscope is used to view unstained specimens with high contrast
dark
Jared was a 48-year-old healthy man who ran a business servicing whirlpool baths and hot tub spas in Columbus, Ohio.
He began to experience ? (shortness of breath) and watery diarrhea.
Jared’s symptoms increased, including a dry cough, ? (muscle pain), nausea, and vomiting. After 6 days, he was admitted to a hospital in Columbus.
The clinician noticed that Jared appeared flushed and had diy mucous membranes. His temperature was 39°C (102.2°F), and his pulse rate was 103 beats per minute. Chest radiographs showed ? with consolidation (formation of a firm mass) of the left lower lobe. His C-reactive protein (CRP, a blood protein produced by the liver) was greater than 220 milligrams per liter (mg/l), a high level that indicates inflammation.
Before onset of symptoms, Jared recalled having cleaned the filter of a hot tub spa at an elite downtown Columbus hotel. The water in hot tubs is filtered and sanitized by chlorination, but it can become contaminated by Gram-negative pathogens. Culture from Jared’s sputum and from the spa filter revealed Gram-? bacilli consistent with Legionella pneumophila. The diagnosis was confirmed by ? microscopy using direct fluorescent antibody (DFA) stain.
The patient received intravenous amoxicillin and clarithromycin antibiotics for 8 days before his condition returned to normal.
dyspnea, mialgia, pneumonia, negative, fluorescence
A ? covalent bond occurs when electrons are shared equally between atoms with similar electronegativity, while a polar covalent bond happens when electrons are shared ? between atoms with different electronegativities
nonpolar, unequally
Hydrophilic means “water-?” and hydrophobic means “water-?”. Hydrophilic substances ? water, while hydrophobic substances ? water.
loving, fearing, absorb, repel
In cells, lipids primarily function as building blocks for cell ?, acting as a barrier to control what ? and exits the cell, while also serving as ? storage molecules
membranes, enters, energy
C₃H₈O₃: this is the molecular structure of ?
glycerol
C₆H₁₂O₆: this is the molecular structure of ?
glucose
The building blocks of a polysaccharide are ?; meaning a polysaccharide is made up of many simple sugars
monosaccharides
? ? replicates new DNA strands by adding nucleotides to a DNA template during PCR, effectively amplifying the target DNA.
Taq polymerase
Primary: ? of amino acids in a polypeptide chain.
Secondary: Local ? into α-helices and β-pleated sheets.
Tertiary: Overall ? shape formed by side chain interactions.
Quaternary: Multiple polypeptide chains assemble into a functional protein ?.
sequence, folding, 3D, complex
When ATP is hydrolyzed to AMP, the free energy change (ΔG) is ? bc it’s an ? reaction.
negative, exergonic
A double ? reaction occurs when two ? compounds exchange their ions to form two new compounds. The reaction typically takes place in ? solution, resulting in the formation of a precipitate, gas, or water.
replacement, ionic, aqueous
First Law: Energy cannot be ? or ?, only converted from one form to another.
Second Law: The ? (disorder) of an isolated system always ? over time.
Third Law: As temperature approaches absolute zero, the entropy of a system approaches a ? value.
created, destroyed, entropy, increases, minimum
Entropy is a measure of ? or ? in a system; the higher the entropy, the greater the disorder.
disorder, randomness
ways a cell can increase the rate of reaction
Increasing ?
Using ?
Increasing ? of reactants
Providing cofactors or coenzymes
temperature, enzymes, concentration
The energy of activation (activation energy) is the ? amount of energy required for a ? reaction to occur. A higher activation energy means the reaction will proceed more ?, while a lower activation energy ? the reaction rate.
minimum, chemical, slowly, increases
The Brønsted-Lowry definition of a weak acid is a substance that ? donates protons (H⁺) to ? or another base in solution, meaning it does not fully ? in water.
partially, water, dissolve
can a weak acid can cross a cell membrane?,
if so, in what form?
yes, typically in its non-ionized form
what kind of molecules can cross phospholipid bilayer
Small ? molecules: Oxygen (O₂), Carbon dioxide (CO₂)
Small ?polar molecules: Water (H₂O), Glycerol
?-soluble molecules: Steroids, Fatty acids, Cholesterol
non-polar, uncharged, lipid
Hypertonic: A solution with a ? concentration of solutes compared to the cell, causing the cell to lose water and ?.
Hypotonic: A solution with a ? concentration of solutes compared to the cell, causing the cell to take in water and ?.
Isotonic: A solution with the ? concentration of solutes as the cell, resulting in no net water movement, and the cell ? its shape.
higher, shrink, lower, swell, same, maintains
an ? is a membrane-bound vesicle formed during endocytosis
a phagosome is a special type of vesicle formed during ?
endosome, phagocytosis
?: The process by which cells take in substances from outside by engulfing them in a vesicle.
endocytosis
Exocytosis: The process by which cells ? substances by ? fusing with the cell membrane, releasing their contents ? the cell.
expel, vesicles, outside
The primary source of antibiotics is ?.
actinomyces
? was the first cellular microbe sequenced
bacteria
In October 2013, Kelsey was a 28-year-old computer programmer who worked for a prominent technology firm in Silicon Valley. In the middle of the night, Kelsey awoke with abdominal cramps and diarrhea. Her temperature spiked as high as 40°C (104°F). She had a bad headache and could not retain sufficient fluids.
After 3 days, her fever subsided, but the diarrhea continued (about 20 times a day) and began showing blood. Kelsey was admitted to the hospital, where she was given intravenous fluids to control her dehydration. The physician asked her about her dietary history preceding the onset of symptoms. Kelsey recalled that, the night before onset, she had eaten rotisserie chicken cooked at the supermarket. An antibody test confirmed the diagnosis of ? enterica serovar Heidelberg. Because of the severity of her symptoms, Kelsey was treated with antibiotics, although sometimes antibiotics may prolong the persistence of Salmonella. When amoxicillin failed to control the infection because of ? resistance, ? was used. Ultimately, Kelsey’s illness was one of more than 400 cases in 23 states traced to contaminated chicken from one California farm. Kelsey recovered, but 3 months later, S. Heidelberg could still be detected in her feces.
Salmonella, bacterial, ciprofloxacin
cholera toxin signaling pathway:
“Big Elephants Always Grab Apples Constantly.”
B: ?- Toxin binds to GM1 ganglioside receptor.
E: ?- Toxin enters the cell via endocytosis and travels to the ER.
A: ? ? release - The A1 subunit is released into the cytoplasm.
G: ? ? modification - A1 modifies the G protein.
A: ? ? activation - G protein activates adenylate cyclase to produce cAMP.
C: Chloride ? - cAMP activates ion channels, leading to chloride and water loss.
binding, endocytosis, A1 Subunit, G protein, Adenylate cyclase, efflux
