236 exam 1 assignments

The nucleocapsid of an icosahedral virus has __________ triangular sides or facets.

20

Suppose 50 cells of Bacterium A, 100 cells of Bacterium B, 500 cells of Bacterium C, and 1,000 cells of Bacterium D are needed to cause an infection, which bacterium is the most virulent?

A

Malaria is an acute illness characterized by fever, chills, headache, weakness, vomiting, cough, diarrhea, and abdominal pain. Four different species of the protozoan parasite Plasmodium are known to cause malaria: P. falciparum, P. malariae, P. ovale, and P. vivax. Humans occasionally become infected with species of Plasmodium that normally infect animals, such as P. knowlesi. In 2017, an estimated 219 million cases of malaria occurred worldwide and 435,000 people died, mostly children in the African Region. About 1,700 cases of malaria are diagnosed in the United States each year. The parasite is most commonly transmitted to humans through the __________.

Bite of an infected female Anopheles mosquito

In 1991, an outbreak of food poisoning occurred at a national conference in the United Kingdom. A detailed postal survey of all conference attendees was carried out to ascertain the cause of the outbreak and 355 questionnaires were returned. Analysis showed that mussels in the seafood buffet were the likely vehicle of infection. A relationship was demonstrated between the amount of mussels consumed and the risk of illness - 18% of individuals who consumed just a mouthful became ill, 32% of individuals who consumed a half portion became ill, and 44% of individuals who consumed a full portion became ill. This is an example of __________.

biological gradient

Autoclave tape is used as a quality control measure to ensure that autoclaves are functioning properly. What happens to the tape after exposure to proper autoclave temperature (121°C-135°C)?

black diagonal lines appear on tape

tinea corporals is an infection of

body trunk

Ms. Sultana, a 25-year-old female, developed a severe respiratory tract infection. She was prescribed a 10-day course of tetracycline by a physician. Tetracycline is a drug that can act against both Gram-positive and Gram-negative bacteria. Based on this characteristic, it can be classified as a __________.

broad spectrum antibiotic

Rabies is a vaccine-preventable viral disease which occurs in more than 150 countries and territories. In up to 99% of cases, domestic dogs are responsible for rabies virus transmission to humans. The virus is spread to humans through bites or scratches, usually via saliva. Initial symptoms of rabies include a fever with pain and unusual tingling, pricking, or burning sensation at the wound site. As the virus spreads to the central nervous system, progressive and fatal inflammation of the brain and spinal cord develops. Rabies is almost always fatal following the onset of clinical symptoms. The virus belongs to the Rhabdoviridae family, and is shaped like a/an __________.

bullet

Room air contains less than 1% carbon dioxide. Some bacteria grow better in the laboratory in the presence of increased concentrations of carbon dioxide (usually 5%-10%). These are referred to as __________.

capnophiles

________ can be grown in candle jars

capnophiles

Streptococci exist as

chains

Staphylococci exist as

clusters

_____________ refers to the initial act of a microbe establishing its presence in the host.

colonization

Over the years, microbiologists have developed several techniques to stain bacteria. Some procedures are used to merely stain bacterial cells so that one can determine their size, shape, and morphologic arrangement (e.g. staining with safranin, staining with methylene blue). Other procedures are used to determine structural elements of bacterial cells (e.g. capsule stains, flagella stains, endospore stains). Yet another category involves procedures that are used to distinguish between groups of bacteria (e.g. Gram-positive versus Gram-negative, acid-fast versus non-acid-fast). What are the procedures in this third category called?

differential staining techniques

__________ are an integral part of the cell wall structure of Gram-negative bacteria that are released during cell lysis and can cause serious, adverse effects in humans (e.g. septicemia).

endotoxins

Plague is a serious disease caused by the Gram-negative bacterium Yersinia pestis. Humans usually get plague after being bitten by a rodent flea that is carrying this bacterium, or by handling an animal infected with plague. Clinical manifestations include a sudden onset of fever, headache, chills, and extreme weakness. Patients may also develop swollen, tender and painful lymph nodes (in bubonic plague), abdominal pain, bleeding and shock (in septicemic plague), or shortness of breath, chest pain and cough (in pneumonic plague). Plague is infamous for killing millions of people in Europe during the Middle Ages. Yersinia pestis makes ATP by aerobic respiration if oxygen is present, but can switch to fermentation if oxygen is absent (i.e. it can thrive in the presence or absence of oxygen). Based on this characteristic, it can be classified as a/an __________.

facultative anaerobe

true or false tinea cruris is an infection on the scalp

false

true or false: Cocci are rod-shaped bacteria

false

__________ are inanimate objects capable of transmitting pathogens.

fomites

possess chitin in their cell walls.

fungi

Penicillin is a widely used antibiotic for treating infections of the middle ear, sinuses, stomach, intestines, bladder, and kidney. Alexander Fleming, a Scottish bacteriologist, discovered it in the year 1928. Several Gram-positive bacteria are sensitive to penicillin because the antibiotic inhibits the synthesis of peptidoglycan, an essential constituent of their cell walls. Penicillin is derived from a cellular microbe called Penicillium notatum, which is a type of __________.

fungus

Mycobacterium is a __________ of acid-fast bacteria, which includes human pathogens such as M. tuberculosis, and M. leprae.

genus

the first phase in both cellular respiration and fermentation.

glycolysis

The bacterium Salinibacter ruber and the alga Dunaliella salina are examples of microbes that thrive in extremely salty environments such as the Great Salt Lake and the Dead Sea. These microbes are categorized as __________.

halophiles

mycoplasmas are pleomorphic because they

have no cell walls

protozoa do not possess

hyphae

Cholera is an infectious disease caused by the bacterium Vibrio cholerae that manifests as severe watery diarrhea, which can lead to dehydration and even death if untreated. The bacterium thrives wherever crowded housing conditions exist, and water and sanitation facilities are suboptimal. The World Health Organization (WHO) estimates that 3 to 5 million new cases occur globally every year.

incidence

India, the second most populated country in the world, was heavily impacted by the novel coronavirus in 2020-2021. More than 412,000 new cases of COVID-19 were reported in India on May 5, 2021.

incidence

The infection control nurse in NewLife Hospital was interested in estimating the proportion of women in the obstetrics ward who developed a surgical site infection after undergoing a Caesarean section for delivery between January 1, 2021 and December 31, 2021.

incidence

receptors

integrins

What is the correct sequence of phases in a bacterial growth curve?

lag phase, log phase, stationary phase, death phase

adhesions

ligands

Cerebrospinal fluid is collected by __________. In this procedure, a needle is inserted into the subarachnoid space between the 3rd and 4th lumbar vertebrae.

lumbar puncture

is a procedure to inhibit the in vitro growth of microbes that involves a combination of freezing and drying. It is commonly used to preserve vaccines, blood samples, and other biological materials in labs.

lyophilization

Which of the following agents is commonly used to "fix" bacteria to a glass microscopic slide?

methanol

Who would be most susceptible to an infection by an opportunistic pathogen?

middle aged female with advanced HIV infection

Mesophiles grow best at

moderate temperatures

Tinea unguium is an infection of

nails

__________ involves the rapid destruction of soft tissues caused by "flesh-eating" strains of Streptococcus pyogenes.

necrotizing fasciitis

Epstein-Barr virus (EBV), also known as human herpesvirus 4, is a member of the herpes virus family. It is one of the most common human viruses, and is found all over the world. EBV spreads most commonly through bodily fluids, primarily saliva. Infection with this virus increases a person's risk of getting nasopharyngeal cancer, as well as a fast-growing cancer of the lymphatic system known as Burkitt lymphoma. EBV is an example of a/an __________ virus.

oncogenic

__________ is an abnormal posture seen in severe tetanus where the back becomes extremely arched due to muscle spasms.

opisthotonus

Diplococci exist in

pairs

Chemotherapy is the use of any chemical (or drug) to treat any disease. Who is considered to be the "Father of Chemotherapy"?

paul ehrlich

Toxins secreted by some algae are known as __________, and toxins secreted by some moulds and fleshy fungi are known as __________.

phycotoxins; mycotoxins

Herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) are common, lifelong infections, which often have no signs or symptoms. Some people may develop painful blisters or sores at the site of infection. According to the National Health and Nutrition Examination Survey (NHANES) conducted in 2015-2016, 47.8% of persons aged 14-49 years were living with HSV-1, and 11.9% of persons aged 14-49 years were living with HSV-2.

prevalence

Tuberculosis (TB) is an infectious disease caused by the bacterium Mycobacterium tuberculosis that spreads from person to person through the air. TB usually affects the lungs, but not everyone with this bacterial infection becomes sick (known as latent TB infection). According to the Centers for Disease Control and Prevention, up to 13 million people in the United States are living with latent TB infection.

prevalence

Feline spongiform encephalopathy (in cats) and bovine spongiform encephalopathy (in cows) is cause by a __________.

prion

__________ is the phase in the course of an infectious disease during which a patient feels like they are "coming down with something". Non-specific signs and symptoms such as mild fever, fatigue, body ache, and headache start appearing.

prodromal period

Which of the following rare infections is caused by a genus of algae?

protothecosis

Protozoa may possess

pseudopodia, flagella, cilia

Clostridium difficile is a rod-shaped bacterium that can cause symptoms ranging from diarrhea to life-threatening inflammation of the colon. Older adults in hospitals or in long-term care facilities are most commonly affected, and the infection typically occurs after the use of antibiotics. The bacteria are passed in feces and can spread to food, surfaces and objects when people who are infected do not wash their hands thoroughly. Touching a contaminated surface may then result in swallowing the bacteria without one's knowledge resulting in infection. What kind of a disinfectant should be used in a healthcare setting to prevent Clostridium difficile infections?

sporicidal

have no visible means of locomotion

sporozoa

Inoculation of a solid medium involves using a sterile inoculating loop to apply a portion of a specimen to the surface of the medium. This process is referred to as __________.

streaking

Sometimes two antimicrobial agents may be used simultaneously to treat an infectious disease. When the use of two drugs produces a degree of pathogen killing that is far greater than that achieved by either drug alone, the phenomenon is known as __________.

synergism

Which of the following steps occurs during the multiplication of animal viruses, but not during the multiplication of bacteriophages?

uncoating

obligate intracellular pathogens

viruses

If a dimorphic fungus is causing a respiratory infection, which of the following might be seen in a sputum specimen from that patient?

yeasts

Brucellosis is a bacterial infectious disease caused by species in the genus Brucella. People can get the disease when they are in contact with infected animals or animal products contaminated with the bacteria. Animals that are most commonly infected include sheep, cattle, goats, pigs, and dogs. Therefore, this is an example of a __________ disease

zoonotic

is a machine that is used to sterilize surgical equipment, lab instruments, and pharmaceutical items using high-pressure steam.

autoclave

tinea barbae is an infection of

beard

Alicyclobacillus is a genus of Gram-variable, rod-shaped, spore-forming bacteria. They are of special interest to the fruit juice industry because common pasteurization techniques do not deactivate their spores. They have been implicated in spoilage of orange, peach, and mango juices, as well as tomato products. Most species grow in the pH range of 2.0-6.0, and none have been demonstrated to grow above a pH of 6.5. These bacteria are categorized as __________.

aciophiles

pilli

adhesion factors

__________ studies test hypotheses in order to evaluate potential causal relationships between an exposure and a disease.

analytic

Green sulfur bacteria and purple sulfur bacteria are phototrophs that are capable of carrying out __________ photosynthesis.

anoxygenic

Solutions such as ethanol and potassium permanganate that can be used to disinfect skin are called __________.

antiseptics

In which part of a thioglycollate broth tube can facultative anaerobes grow?

anywhere

What is the general term used to describe infections caused by viruses spread to people by the bite of infected arthropods?

arboviral disease

Which of the following are common mechanisms by which antimicrobial agents kill or inhibit the growth of bacteria?

CM damage, inhibits cell wall and protein synthesis

places microbes in a state of "suspended animation"

Freezing and drying

bacteremia

NOT septicemia

________ is the lowest temperature at which all organisms of a species (in pure culture) are killed in a specified time period.

thermal death point

In __________, a bacteriophage picks up a short piece of chromosomal DNA from one bacterium during multiplication, and "accidentally" transfers it to another bacterium.

transduction