Microbiology, Ch 12 Nester's 9th

Algae are important environmentally as: - local contaminants. - major producers of oxygen. - supporting fungal growth. - local flora. - major producers of carbon dioxide.

- major producers of oxygen.

Fungi are classified according to their - mode of locomotion. - this is protozoans - cap color. - morphology. - method of sexual reproduction. - mode of nutrition.

- method of sexual reproduction. - found it. slide 18 - The sexual forms (of reproduction) play an important role in FUNGAL CLASSIFICATION and some are commercially valuable.

The human body only contains bacteria during illness. True or Flase False Viruses, viroids and prions all: - operate intracellularly. - may be considered acellular agents of disease. - contain DNA. - infect only animals. - operate intracellularly AND may be considered acellular agents of disease.

- operate intracellularly AND may be considered acellular agents of disease.

Fungi that are important for fermentation of fruits: - grow well at neutral pH. - are mushrooms. - are obligate aerobes. - secrete degradative enzymes. - All of the choices are correct.

- secrete degradative enzymes.

Algae

-May be green, red, or brown. -Lack roots, stems, leaves, and vascular tissues that are found in terrestrial plants. -Some marine produce neurotoxins that can be concentrated in shellfish and pose a risk of paralytic shellfish poisoning to humans who consume the shellfish. -Both asexual and sexual reproduction occurs among the diversity of species. -Most have a plantlike cell wall composed of cellulose.

Protozoa

-Most protozoa are motile via pseudopods, flagella, cilia, or undulating membranes. -Cysts enable parasites to survive during passage from one host to the next. -While living in the gut of their host, intestinal parasites are usually in the trophozoite form. -As a group exhibit both asexual and sexual reproduction.

Helminths

-The major organ system apparent in tapeworm proglottids is the reproductive system. -Some helminth infections involve more than one intermediate host. -Either eggs or larval stages may be infectious, depending on the species. -Parasitic lack a complete digestive system and they absorb nutrients directly through their cuticles. -Humans can serve as either definitive or intermediate hosts of flatworms.

Some fungi reproduce sexually by forming----- which are sexual spores contained within a sac structure.

-ascospores

Rhizopus stolonifer, the common black bread mold, forms asexual spores called----- which are contained in a sac at the end of aerial hyphae.

-sporangiospores

Which of the following statements about helminths is FALSE? - Some have male and female reproductive organs in one animal. - They are heterotrophic. - They have eukaryotic cells. - They are multicellular animals. - All are parasites.

- All are parasites. Some are parasites. Helminths are worms, a type of animal.

Fungi that are important for fermentation of fruits: - are yeasts. - are facultative anaerobes. - grow well at acid pH. - secrete enzymes that degrade organic molecules. - All of the choices are correct.

- All of the choices are correct

Which of the following statements regarding protozoa is FALSE? - Some protozoa are parasitic. - All protozoa lack mitochondria. - Protozoa are unicellular organisms. - Some protozoa are photosynthetic. - Trichomoniasis is caused by a protozoan.

- All protozoa lack mitochondria.

Yeast infections are caused by: - Saccharomyces cerevisiae. - Candida albicans. - Histoplasma. - Penicillium. - Aspergillus.

- Candida albicans.

Which of the following organisms is photoautotrophic protozoan? - Phytophthora - plasmodial slime mold - cellular slime mold - Euglena - oomycote

- Euglena

What is a definitive host in the life cycle of a parasite? 1. An organism in which the parasite multiplies asexually, without causing any damage to the host. 2. An organism in which either sexual reproduction or asexual reproduction of the parasite occurs. 3. An organism in which sexual reproduction or the adult form of a parasite occurs. 4. An organism from which a parasite typically is not passed to another host, so that the parasite cannot complete its life cycle. 5.An organism in which asexual reproduction or an immature form of a parasite occurs.

An organism in which sexual reproduction or the adult form of a parasite occurs.

Which phylum of protozoa contains organisms that are non-motile, obligate intracellular parasites? - Euglenozoa - Amoebozoa - Apicomplexa - ciliates

Apicomplexa

Members of this group have hard exoskeletons and jointed appendages. Members of this group serve as vectors, transmitting several different viruses, bacteria, and protozoan parasites between hosts.

Arthropods

Please select the FALSE statement regarding arthropod vectors. - Mechanical vectors simply transfer a pathogen from one surface to another. - The incidence of vector-borne diseases can be decreased by controlling the vector or the infected hosts. - Biological vectors play an essential role in the life cycle of the pathogen. - Arthropods are very specific and always bite only one type of host. - Some arthropods cause disease even when they do not act as a vector.

Arthropods are very specific and always bite only one type of host.

Which of the following statements regarding fungi is FALSE? A-Fungi reproduce by forming asexual or sexual spores. B-Most fungi grow well in acidic culture condition. C-Fungi tolerate low moisture conditions. D-Most fungi are pathogenic for humans. E-Fungi are eukaryotic heterotrophs.

D-Most fungi are pathogenic for humans.

In the malaria parasite life cycle, humans are the ________ host, while mosquitoes are the ________ host as well as the vector. A-vector, intermediate B-intermediate, intermediate C-temporary, final D-intermediate, definitive E-definitive, intermediate

D-intermediate, definitive The parasite which causes malaria (called Plasmodium) requires two different hosts—a vertebrate intermediate host, such as a human, and an insect definitive host, also known as the vector. For the types of malaria which infect humans and other mammals, the vector is always a mosquito of the genus Anopheles.

The group of Fungi in which sexual reproduction has not been observed is: Deuteromycetes has been further classified using:

Deuteromycetes. rRNA analysis

Which are the three ways in which fungi cause illness in humans? 1. Hypersensitivity - person has allergic reaction to fungal components. 2. Intoxication - fungus produces a toxin that is ingested. 3. Immune suppression - fungus destroys all red blood cells. 4. Infection - fungus grows on body as a mycosis. -- 1. 1, 2, and 4 2. 4 only 3. 2, 3, and 4 4. 1, 3, and 4 5. 1, 2, and 3

1. 1, 2, and 4

One of the organisms that may cause red tide is: 1. dinoflagellates. 2. euglenids. 3. diatoms. 4. green algae. 5. brown algae.

1. dinoflagellates.

One of the greatest causes of human deaths through time has been due to: 1.Plasmodium spp. 2.Giardia spp. 3.Escherichia spp. 4.Trypanosoma spp. 5.Histoplasma spp.

1.Plasmodium spp. - causes malaria

The return of carbon dioxide to the atmosphere and nitrogen to the soil is due to the action of: 1. fungi and viruses. 2. fungi and bacteria. 3. viruses and plants. 4. plants and bacteria. 5. bacteria and viruses.

2. fungi and bacteria.

Lice and mites... 1. cause Lyme disease. 2. may both be spread by personal contact. 3. are both arachnids. 4. are intestinal parasites. 5. both cause respiratory illness.

2. may both be spread by personal contact.

Once Y. pestis is in the human host, it is ingested by macrophages. Conditions within the macrophage activate certain genes in the bacterium, one of which is a gene for a capsule production. The capsule: 1.allows the bacteria to survive excess heat. 2.allows the bacteria to avoid phagocytosis. 3.provides a source of nutrients for the bacteria. 4. allows the bacteria to float in water. 5.allows the bacteria to exchange DNA with other bacteria.

2.allows the bacteria to avoid phagocytosis.

Protozoans are an important part of the food chain, ingesting large numbers of: 1. other protozoans. 2. bacteria and fungi. 3. bacteria and algae. 4. fish and crabs. 5. shellfish and algae.

3. bacteria and algae.

Sarcodina move by means of: 1. microvilli. 2. apicomplexans. 3. pseudopodia. 4. flagella. 5. cilia.

3. pseudopodia.

Select the TRUE statement regarding algae. 1. Algae are plants and therefore possess a highly organized vascular system. 2. Algae are generally saprophytic, living off dead and decaying matter. 3. Some algae can directly cause infectious diseases in humans and other animals. 4. Although most algae have a cellulose/pectin cell wall, some algae lack a cell wall. 5.Algae always reproduce sexually, producing both haploid and diploid generations.

4. Although most algae have a cellulose/pectin cell wall, some algae lack a cell wall.

The pH at which most fungi thrive is ________.

5 - some fungal species can grow in concentrations of salts, sugars or acids that inhibit the growth of most bacteria. Fungi can grow on pH 2.2-9.6 and usually grow well at pH 5.0 or lower.

Which disease is INCORRECTLY matched with its arthropod vector? 1. Dengue fever—mosquitoes 2. Malaria—Anopheles mosquito 3. Lyme disease—ticks 4. Plague—fleas 5. African sleeping sickness—sand fly

5. African sleeping sickness—sand fly

Sarcoptes scabiei

The mite that causes scabies in humans and mange in dogs.

Which of the statements BEST describes tapeworms? - They may be transmitted by eating undercooked meat. - They do not have a digestive system AND they may be transmitted by eating undercooked meat. - They have a complicated digestive system. - They have a complicated digestive system AND they may be transmitted by eating undercooked meat. - They do not have a digestive system.

They do not have a digestive system AND they may be transmitted by eating undercooked meat.

Most fungi are: - obligate anaerobes. - microaerophiles. - photosynthetic. - aerobes or facultative anaerobes. - obligate aerobes.

aerobes or facultative anaerobes

Agar is obtained from: - protozoans. - bacteria. - plants. - algae. - yeasts.

algae

Haustoria... 1. are specialized hyphae used by parasitic fungi. 2. are a form of parasitic protozoan. 3. are the reproductive form of protozoans. 4. are a type of root used by all climbing plants. 5. refers to the reproductive structure formed by slime molds.

are specialized hyphae used by parasitic fungi.

Mycorrhizae: - are vital for the survival of lichens AND are vital for the survival of many plants. - are vital for the survival of many plants AND are used in the production of wine, beer, and bread. - increase the absorptive ability of roots AND are used in the production of wine, beer, and bread. - are used in the production of wine, beer, and bread AND are vital for the survival of lichens. - are vital for the survival of many plants AND increase the absorptive ability of roots.

are vital for the survival of many plants AND increase the absorptive ability of roots.

Most of the medically important multicellular parasites are arthropods or helminths, true or false?

True

T/F - Viruses, viroids, and prions are obligate intracellular agents.

True

Typically, arthropods serve as vectors of disease, while helminths directly cause disease, true or false?

True

Why would all protozoa be expected to require large amounts of water in their habitats? - They require water to help them during photosynthesis by providing an electron source. - Without being in water, they would quickly undergo plasmolysis (due to their small size) and die. - Without being in water, they would quickly dehydrate (due to their small size) and die. - They require water to move around in to seek food particles and would be unable to move without water. - None of the statements is correct.

Without being in water, they would quickly dehydrate (due to their small size) and die.

Which of the following are diseases caused by protozoa? 1. Schistosomiasis, amebiasis, AND primary amebic meningoencephalitis. 2. Dengue fever, malaria, AND plague. 3. Amebiasis, malaria, AND plague. 4. Giardiasis, malaria, AND toxoplasmosis. 5. Giardiasis, malaria, AND trichinellosis.

Giardiasis, malaria, AND toxoplasmosis.

Paralytic shellfish poisoning occurs when humans eat shellfish that have fed on: - Vibrio cholerae. - Salmonella species. - Volvox species. - E. coli. - Gonyaulax species.

Gonyaulax species.

Members of this group come in flat or round forms, and although many parasitize animals, there are also free-living forms. Parasitic members of this group often have complex life cycles involving one or more intermediate hosts in which larvae develop.

Helminths

Yersinia pestis is transmitted by fleas. The organism forms biofilms in the digestive tract of infected fleas, often blocking the tract. This prevents the flea from feeding properly, causing bacteria to be regurgitated into the bite wound that the flea has made. In this situation, the flea is a: - dead-end host. - mechanical vector. - mechanical host. - biological vector. - biological host.

biological vector

Which of the following statements is true about the relationship between natural selection and mutation? A) Natural selection creates mutations. B) Mutations assist natural selection. C) Mutations produce natural selection. D) Natural selection does not rely on mutations. E) None of the above are true.

No answer - I think it's B.

Which of the following best explains why Bruce Ames added a rat liver step to his mutagen testing? A) It better modeled how carcinogens act in the body. B) The rat liver extracts increased the mutation rate in the bacteria. C) Rat liver cells detected the mutagens. D) The rat liver produces histidine. E) None of the above are correct.

No answer but I think it's A. - add rat liver to the Ames test so see if a suspected mutagen becomes a problem when in the presence of bodily enzymes.

Are all fungi detrimental (bad) for other organisms?

No—it depends on the fungus and the relationship it has with the other organism. Some fungi can form a symbiotic relationship with plant roots that increases their nutrient and water absorption. This is good.

Coccidioidomycosis is: - a protozoan disease caused by Candida sp. - a viral disease caused by Coccidioides sp. - a protozoan disease caused by Coccidioides sp. - a fungal disease caused by Candida sp. - a fungal disease caused by Coccidioides sp.

a fungal disease caused by Coccidioides sp. - Valley Fever - The name and the myco- = fungal was the give away.

Macroscopic algae possess a special structure that acts as an anchor and is commonly called: 1. the stipe. 2. roots. 3. the bladder. 4. a thallus. 5. a holdfast.

a holdfast

Plague is caused by Yersinia pestis, a Gram-negative facultatively anaerobic rod. It is non-motile and grows best at 28°C. Because you are a microbiology student, you know that the organism is: - a mesophile that cannot grow when oxygen is present. - a mesophile that grows best in the presence of oxygen but can also grow without it. - a mesophile that grows best without oxygen but can also grow when oxygen is present. - a psychrophile that grows best in the presence of oxygen but can also grow without it. - a psychrophile that grows best without oxygen but can also grow when oxygen is present.

a mesophile that grows best in the presence of oxygen but can also grow without it.

Phthirus pubis, 1. are transmitted by mosquitoes 2. cause "crabs" 3. Transmit bacterial disease 4. Infect the blood 5. Are biological vectors

causes "crabs"

Which of the following pairs is mismatched? - nematodes : complete digestive tract - cestodes : all are free-living - trematodes : flukes - nematodes : many are free-living - cestodes : segmented body made of proglottids

cestodes all are free-living - these are tapeworms.

All fungi have ________ in their cell walls. chitin cellulose peptidoglycan pectin ergesterol

chitin

The site in a photosynthetic eukaryotic cell where photosynthesis occurs is the: - carotenoid. - Golgi. - chloroplast. - nucleus. - mitochondria.

chloroplast.

Convergent evolution

explains the morphological similarity yet major genetic differences found between slime molds and fungi AND refers to two different organisms that develop similar characteristics in adaptation to similar environments

Convergent evolution... 1. refers to two different organisms that develop similar characteristics in adaptation to similar environments 2.explains the morphological similarity yet major genetic differences found between slime molds and fungi AND refers to two different organisms that develop similar characteristics in adaptation to similar environments. 3. explains the morphological similarity yet major genetic differences found between slime molds and fungi.

explains the morphological similarity yet major genetic differences found between slime molds and fungi AND refers to two different organisms that develop similar characteristics in adaptation to similar environments.

Sexual reproduction in algae involves meiosis that results in the production of: 1. spores with twice as much DNA as the parental cells. 2. gametes with the same amount of DNA as in the parental cells. 3. gametes with half the amount of DNA as in the parental cells. 4. swarming cells with the same amount of DNA as the parental cells. 5. spores with the same amount of DNA as the parental cells.

gametes with half the amount of DNA as in the parental cells.

Nematodes: - includes the trematodes. - are carried by bacteria and fungi. - may enter the gastrointestinal tract or the blood. - only infect aquatic plants. - have flat, segmented bodies.

may enter the gastrointestinal tract or the blood.

Dimorphic fungi - may grow as mycelia or yeast AND are mushrooms. are strictly hyphae AND are often associated with disease in humans. - are often associated with disease in humans AND are mushrooms. - are strictly yeasts AND are often associated with disease in humans. - may grow as mycelia or yeast AND are often associated with disease in humans.

may grow as mycelia or yeast AND are often associated with disease in humans.

Schizogony: 1. means multiple fissions AND is performed by protozoa. 2.is performed by protozoa AND is a type of reproduction. 3.is a form of reproduction AND means multiple fissions. 4.is performed by bacteria AND is performed by protozoa. 5.means multiple fissions AND is performed by bacteria.

means multiple fissions AND is performed by protozoa.

The most necessary habitat requirement of protozoa is: 1. Light 2. Moisture 3. UV light 4. basic pH 5. heat

moisture

The terms yeast, mold, and mushrooms refers to: - fungal - morphology. - nutrition. - reproduction. - parasites. - staining.

morphology

Fungal diseases are generally referred to as:

mycoses

Algae: - are always saprophytic or parasitic. - are only found in the soil. - have a vascular system similar to that of plants. - often grow in areas where other forms of life may have difficulty. - are strictly macroscopic organisms.

often grow in areas where other forms of life may have difficulty.

Pediculus humanus

only uses humans as a host AND can transmit a bacterial disease

Pediculus humanus... 1. only uses humans as a host AND is carried by mosquitoes. 2. is an obligate intracellular parasite AND only uses humans as a host. 3. can transmit a bacterial disease AND only infects feet. 4. only uses humans as a host AND can transmit a bacterial disease. 5. only infects feet AND can transmit a bacterial disease.

only uses humans as a host AND can transmit a bacterial disease.

Free-floating, photosynthetic organisms found in marine environments are blue-green algae. phytoplankton. omega-3s Bucella. krill.

phytoplankton

Gonyaulax... 1. infects the nervous system of humans AND is a monoflagellate. 2. produces a non-protein enterotoxin AND is a dinoflagellate. 3. produces a protein neurotoxin AND is a dinoflagellate. 4. is a monoflagellate AND produces a non-protein neurotoxin. 5. produces a non-protein neurotoxin AND is a dinoflagellate.

produces a non-protein neurotoxin AND is a dinoflagellate.

The ability to exist as either a trophozoite or a cyst is characteristic of many: - bacteria. - archaea. - protozoa. - fungi. - viruses.

protozoa

Single-celled eukaryotic organisms that lack chlorophyll include: - yeasts AND cyanobacteria. - algae AND yeasts. - protozoa AND yeasts. - protozoa AND cyanobacteria. - algae AND archaea.

protozoa AND yeasts.

When cellular slime molds run out of food, they form a: 1. bladder. 2. rhizoid. 3. myxamoeba. 4. plasmodium. 5. slug.

slug

Lyme disease is transmitted by

ticks

From Ch 1 - The work of Tyndall and Cohn:

was used to explain why others investigating spontaneous generation had obtained results that were opposite of those obtained by Pasteur

You and your exercise buddy decide to go to Yosemite National Park to hike the famous El Capitan trail. You book your trip through a well known agency but before you leave for your vacation, you learn that there have been two cases of plague reported in people who recently visited a different area of the park. Your friend is anxious and tells you he thinks that plague is really dangerous and kills people everyone who gets it. He points out that this disease killed a lot of people during the Middle Ages, and says he doesn't want to do the trip after all. You decide to do some research on the plague and its causative agent before making a decision about your trip. Which of the following is NOT a vector? - Fly - Water - Tick - Mosquito - Flea

water

Plant pathology grew in importance as a field of study after it was shown that the Irish potato blight was caused by: - viruses. - bacteria. - water molds. - fungi. - amoeboid protozoa.

water mold

In the late nineteenth century, immigration from Ireland to the United States occurred in high numbers due to an infection of potatoes by:

water molds

Fungi capable of dimorphism grow either as: - yeast-like or mycelium. - rhizoids or hyphae. - spores or mushrooms. - germ tubes or buds. - yeast-like or mushrooms.

yeast-like or mycellium

Members of this group cause malaria and diarrheal illnesses such as amebiasis and giardiasis. Many members of this group are motile by means of cilia, flagella, or pseudopods

Protozoa

This group includes unicellular as well as filamentous forms, a number of which cause infections. Members of this group produce a variety of different reproductive spores and filaments referred to as hyphae.

Fungi

Which of the statements regarding Naegleria fowleri is FALSE? - Once in a human host, it assumes an amoeboid form. - It is swims though water as a flagellated form. - It causes primary amebic meningoencephalitis (brain eating disease). - It is a small, Gram-negative, flagellated diplococcus. - It forms a cyst under adverse environmental conditions.

- It is a small, Gram-negative, flagellated diplococcus. - an amoeboid Protozoa Naegleria fowleri infects people when water containing the AMOEBA enters the body through the nose. This typically occurs when people go swimming or diving in warm freshwater places, like lakes and rivers. The Naegleria fowleri ameba then travels up the nose to the brain where it destroys the brain tissue. - can't live in salt or treated water.

Which of the following are characteristics of fungi? -They have a nuclear membrane AND their cell wall contains cellulose. - Their cell wall contains chitin AND they use nutrients from dead or decaying organic matter. - Their cytoplasmic membrane contains ergesterol AND they are always multicellular. - They have a peptidoglycan cell wall AND they may be photosynthetic. - Their cell wall contains cellulose AND they use nutrients from dead or decaying organic matter.

- Their cell wall contains chitin AND they use nutrients from dead or decaying organic matter.

Streptococcus pyogenes would be - beta hemolytic and catalase negative. - beta hemolytic and catalase positive. - alpha hemolytic and catalase negative. - alpha hemolytic and catalase positive.

- beta hemolytic and catalase negative.

The encysted larva of the beef tapeworm is called a: - metacercaria. - redia. - proglottid. - cercaria. - cysticercus.

- cysticercus.

Ringworm is caused by a(n)? - trematode. - nematode. - fungus. - cestode. - protozoan.

- fungus

Helminthic diseases are usually transmitted to humans by: - aerosols. - vectors. - respiratory route. - genitourinary route. - gastrointestinal route.

- gastrointestinal route.

All of the following are characteristic of the Platyhelminthes EXCEPT that they? - are multicellular animals. - are hermaphroditic. - are dorsoventrally flattened. - can be divided into flukes and tapeworms. - have highly developed digestive and nervous systems.

- have highly developed digestive and nervous systems.

Giardia and Trichomonas are unusual eukaryotes because they: - are motile. - lack nuclei. - lack mitochondria. - do produce cysts. - do not produce cysts.

- lack mitochondria. Giardiasis is an intestinal infection in humans and animals, caused by a microscopic protozoan parasite Giardia duodenalis (also known as G. intestinalis or G. lamblia). "Giardia is not a "worm", bacteria or virus." Trichomoniasis (or "trich") is a very common sexually transmitted disease (STD). It is caused by infection with a protozoan parasite called Trichomonas vaginalis. Although symptoms of the disease vary, most people who have the parasite cannot tell they are infected.

A.Wherein a parasite sexually reproduces B. Taxonomic category of related organisms, usually containing several species; the first name of an organism in the Binomial System of Nomenclature C. Flowchart of tests used for identifying an organism; each test gives either a positive or negative result D. Characteristic structures of motility in spirochetes E. The group of Gram-negative oxygenic phototrophs genetically related to chloroplasts

A. Definitive Host B. Genus C. Dichotamous Key D. Endoflagella E. Cyanobacteria

A.In molecular biology, a piece of DNA acting as a carrier of a cloned fragment of DNA; in epidemiology, any living organism that can carry a disease-causing microbe, most commonly arthropods such as mosquitoes and ticks B. Organism utilizing nutrients from dead and decaying matter C. Isolated from Agrobacterium tumefaciens, it allows those organisms to cause tumors in plants; a derivative is used as a vector to introduce DNA into plants by genetic engineering D. Pattern of fragment sizes obtained by digesting DNA with one or more restriction enzymes E. Evolutionary relatedness of organisms

A. Vector B. Saprophyte C. Tumor-inducing (Ti) plasmid D. Restriction fragment length polymorphism (RFLP) E. Phylogeny

A. A poisonous substance made by Aspergillus flavus B. Lacking O2 C. Microbiological group of strains having a characteristic biochemical pattern different from other strains; also called a biovar D. Biological production of light E. Organism that obtains energy by oxidizing organic compounds such as glucose

A. aflatoxin B. anoxic C. biotype D. bioluminescense E. chemoorganotroph

A. Phototrophic organism producing O2 B. A common name for members of the family Enterobacteriaceae C. Roundworms D. The group of Gram-positive bacteria generating lactic acid as the major end product of their fermentive metabolism E. A method of distinguishing strains that relies on determining the nucleotide sequence of select DNA regions

A.Oxygenic phototroph B. Enterics C. Nematodes D. Lactic Acid Bacteria E. Multilocus Sequence Typing

Members of this group generally don't cause infections, but some produce neurotoxins that cause intoxications in animals that consume them. Members of this group are found predominantly in aquatic environments.

Algae

Fungi are important in: - food production. - disease of plants. - food spoilage. - production of antibiotics. - All of the choices are correct.

All of the choices are correct.

Trichomonas vaginalis can be distinguished from other parasitic protozoa by which of the characteristics listed below? A-It is usually found in drinking water and is associated with fecal contamination. B-It has an undulating membrane, infects the vagina, and is frequently transmitted by sexual contact. C-It is a photosynthetic organism that lives in fresh water. D-It infects Anopheles mosquitoes and can be transmitted by a bite.

B-It has an undulating membrane, infects the vagina, and is frequently transmitted by sexual contact.

Which of the following statements regarding protozoa is FALSE? A-Some protozoan pathogens are transmitted by arthropod vectors. B-Most protozoa reproduce asexually. C-Nearly all protozoa cause disease. D-Protozoa are common in water and soil. E-Protozoa are unicellular eukaryotes.

C-Nearly all protozoa cause disease.

Serological methods : - are useful in identifying bacteria. - rely on the specificity of an antibody-antigen interaction. - may be simple and rapid. - All of the choices are correct.

Ch 11 - - All of the choices are correct.

A clever technique that streamlines the identification of auxotrophic mutants is - gas chromatography. - replica plating. - direct selection. - reversion

Ch 11 - Replica plating - auxotroph = a mutant organism (especially a bacterium or fungus) that requires a particular additional nutrient which the normal strain does not.

A researcher noted in a bacterium that there were more mutations in stretches of DNA having higher proportions of thymine than the other bases. Which is the most probable explanation for this observation? A) Thymine is easily converted to uracil by mutagens. B) The other bases are not prone to mutation. C) Thymine mutations cannot be repaired by the SOS system. D) Thymine dimers are more likely to form in those stretches. E) Most mutagens do not alter thymine.

D) Thymine dimers are more likely to form in those stretches.

Why were the slime molds and water molds once considered to be fungi? - They have the same material in their cell walls (chitin) that fungi possess. - Early identification methods focused on appearances rather than genetic similarities/differences. - Early identification methods focused on appearances rather than biochemical characteristics. - Water molds and slime molds are STILL considered to be fungi. - Water molds and slime molds always occur in the same habitats as fungi.

Early identification methods focused on appearances rather than genetic similarities/differences.

Why would it be more difficult to treat diseases in humans caused by members of the Eukarya than diseases caused by the Bacteria?- - Eukaryotic microbes (unlike prokaryotes) often secrete compounds that breakdown and eliminate drugs used against them. This makes them much harder to effectively eliminate than bacteria. - Multicellular organisms always have their own immune systems for protection, so any treatment we develop needs to overcome this built-in protection mechanism. - Since bacteria are so much simpler (being single-celled) than multi-cellular eukaryotic microbes, they are naturally easier to kill off. - Eukaryotic pathogens multiply much more effectively in a human host than bacterial pathogens do; they attain extremely high numbers in the host, making it very difficult to get rid of them. - Eukaryotic microbes use many of the same enzymes and systems as humans, so we lose the ability to target certain molecules that might be present ONLY in the cell type we want to eliminate.

Eukaryotic microbes use many of the same enzymes and systems as humans, so we lose the ability to target certain molecules that might be present ONLY in the cell type we want to eliminate.

Algae have a vascular system very similar to that found in plants, true or false?

False

Protozoans are eukaryotes and as such will always possess a nucleus, mitochondria, and chloroplasts, true or false?

False

T/F - Fungi are often capable of locomotion through the use of flagella.

False

T/F - Slime molds and water molds are types of fungi.

False

T/F - Algae may directly infect humans and cause disease.

False - indirectly - toxins

Diatoms are algae whose silicon dioxide-containing shells are useful economically as: 1. Fertilizers 2. Filters 3. Stabilizers 4. Agar 5. Thickeners

Filters

Which are not arthropods? - Mosquitoes - Flukes - Lice - Fleas - Ticks

Flukes - flukes (trematodes) are helminths (parasitic worms) - arthropods are insects and arachnids

How does Ascaris lumbricoides, an intestinal parasite, cause choking and pulmonary symptoms in some people? - Ingested Ascaris larvae penetrate intestinal capillaries, from where they are carried to the lungs, causing coughing and shortness of breath. - Ascaris is a pulmonary parasite; it only enters the intestine of people with other lung conditions, including asthma. - Ascaris larvae are highly allergenic; when they are ingested, they cause an allergic reaction which includes coughing. - People inadvertently inhale Ascaris worms when they bring contaminated food close to their mouths; these cause pulmonary blockages. - Ascaris, being anaerobic, form large cysts in pulmonary tissue; these accumulate in the lungs, causing coughing.

Ingested Ascaris larvae penetrate intestinal capillaries, from where they are carried to the lungs, causing coughing and shortness of breath.

How would increased travel lead to increased spread of multicellular eukaryotic parasites? - Many eukaryotic parasites depend on vectors (often small blood-sucking insects) for transmission, so moving an infected individual into an area with new vectors and new susceptible humans would increase spread. - It really would NOT; most individuals are screened for parasitic infections prior to traveling out of highly infected areas. We also have quarantine abilities at customs stations for individuals entering the United States. - Eukaryotic parasites are too small to travel great distances effectively; by hitching a ride on luggage, clothing, fruit/vegetables, and other food products, they can enter new geographic areas. - Traveling generally weakens a person's immune system, making them vulnerable to parasitic eukaryotes in any new place that they visit. - Many eukaryotic parasites are transmitted directly from person to person via airborne transmission, so getting an infected individual onto a plane of susceptible individuals would increase spread.

Many eukaryotic parasites depend on vectors (often small blood-sucking insects) for transmission, so moving an infected individual into an area with new vectors and new susceptible humans would increase spread.

You and your exercise buddy decide to go to Yosemite National Park to hike the famous El Capitan trail. You book your trip through a well known agency but before you leave for your vacation, you learn that there have been two cases of plague reported in people who recently visited a different area of the park. Your friend is anxious and tells you he thinks that plague is really dangerous and kills people everyone who gets it. He points out that this disease killed a lot of people during the Middle Ages, and says he doesn't want to do the trip after all. You decide to do some research on the plague and its causative agent before making a decision about your trip. Please select the FALSE statement regarding plague and its transmission. - People can contract plague when they are bitten by fleas from rodents infected with the causative organism. - Y. pestis is typically transmitted by the bites of infected fleas, an example of biological transmission. Plague is caused by a Gram-negative organism and is thus completely untreatable with antibiotics. - Yersinia pestis is a Gram-negative organism and thus possess an outer lipopolysaccharide layer. - The incidence of vector-borne diseases such as plague can be decreased by controlling the vector or the infected hosts.

Plague is caused by a Gram-negative organism and is thus completely untreatable with antibiotics. - you can use antibiotics on G-. - The three main antimicrobial agents recommended to treat plague are streptomycin, tetracycline, and chloramphenicol (1). Streptomycin remains the drug of choice. See? - is a Gram-negative, nonmotile, rod-shaped, coccobacillus bacteria, with no spores. It is a facultative anaerobic organism that can infect humans via the Oriental rat flea. It causes the disease plague, which takes three main forms: pneumonic, septicemic and bubonic plagues.

Which of the following definitions is CORRECT? - Zooplankton—microscopic free-floating photosynthetic organisms. - Saprophytes—organisms that take in nutrients from dead and decaying matter. Proglottids—short, non-segmented, bilaterally symmetrical flatworms. Kinetoplastids—a group of protozoa that penetrate host cells by means of a structure called an apical complex. Mycelium—thread-like structure that characterizes the growth of most fungi and some bacterial species.

Saprophytes—organisms that take in nutrients from dead and decaying matter. - zoo = animal - flatworms (Platyhelminthes) - proglottids are the tapeworm segments with both male and female reproductive structures. - Apicomplexans have the apical complex. - the threadlike structures are filaments and a visible mass of them is the mycellium.

Please select the INCORRECT statement regarding helminths and the diseases they cause. - Sometime helminth eggs are ingested on the surface of contaminated foods. For example, pinworm eggs (Enterobius vermicularis) may be transmitted a food surface. - Some helminths are inadvertently ingested. For example, Onchocerca volvulus, the cause of River blindness, is transmitted by drinking contaminated water or eating fish carrying this parasite. - Some helminths are inadvertently eaten with food. For example, eating undercooked pork containing Trichinella spiralis larvae is the most common cause of trichinellosis. - Some helminths burrow into people. For example, immature forms of hookworm larvae live in the soil and can burrow through human skin. - Some helminths are transmitted through insect bites. For example, Wuchereria bancrofti, the cause of elephantiasis, is transmitted by mosquitoes.

Some helminths are inadvertently ingested. For example, Onchocerca volvulus, the cause of River blindness, is transmitted by drinking contaminated water or eating fish carrying this parasite. - it is transmitted by black flies

A researcher discovered a mutation in bacteria that causes rapid degradation of the bacterial DNA. Which of the following provides the best explanation of the mutation? A) Restriction enzyme function was hindered by the mutation. B) The mutation increased DNA methylation. C) Methylation of the bacterial DNA was decreased by the mutation. D) The mutation disabled SOS repair. E) Thymine dimers were not repaired as a result of the mutation.

There was no answer but I think it's C. Why? Unmethylated isn't seen as self and is destroyed by restriction enzymes.

Some arthropods cause disease even when they do not act as a vector. Which of the following is an example of this? - Dust mites do not transmit infectious disease, but inhalation of the mites and their waste products can sometimes trigger asthma. - The larvae of some mites are called "chiggers" and may cause intense itching where they attach and feed on fluids within skin cells. - Scabies is characterized by an itchy rash caused by allergic reactions to female mites that have burrowed into the outer layers of skin. - The pubic louse is commonly transmitted during sexual intercourse and can cause an unpleasant itch associated with "crabs." - These are all examples of the situation described.

These are all examples of the situation described.

Which statement about aflatoxins is NOT true? They are possible carcinogens. They are produced by Aspergillus. They are toxins. They are produced by Candida. They may be found in peanuts.

They are produced by Candida.

Which of the following statements regarding tapeworms is FALSE? - They absorb nutrients from the host's gut through their skin. - A single worm contains broth male and female reproductive organs. - They do not have a digestive system. - They complete their life cycle in a single host. - They can sometimes cause neurological signs and symptoms in the host.

They complete their life cycle in a single host. -tapeworms don't have a complete digestive system because they latch on and absorb nutrients from the host's gut through their SKIN - the SCOLEX is the head with suckers or hooklets, attached by the neck to PROSTIGLIDS that have both male and female reproductive parts so that as the worm elongates the segments farther way are full of fertilized eggs that come off and get pooped out. - they can sometimes cause neurological signs and symptoms in the host and no, they don't live their whole lives in one host - some use fleas, rabbits, deer, sheep, etc for their INTERMEDIATE HOST