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z Micro test 2

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What is a cell without a nucleus called?
A prokaryotic cell
What are the three primary regions of the prokaryotic cell?
The Cell Membrane, Cytoplasm, and the DNA region
The nuclear membrane is characteristic of what type of cell?
The eukaryotic cell
Name the four different types of appendages and their general function.
Flagella and Periplasmic flagella provide motility to the cell. Pili and Fimbriae provide attachment for the cell
Name the three structures found within the cell envelope.
Name the five structures found in the cytoplasm.
True or False: The Cell Wall is part of the Cytoplasm.
False. It is part of the cell envelope
T/F: Capsules and slime layers are part of the Glycocalyx which function as a part of the cytoplasm.
False, the Glycocalyx is part of the cell envelope.
T/F: Chromatin bodies are freely found throughout the cytoplasm.
False, they are located in DNA regions (Nucleoids) in the Cytoplasm.
T/F: Sex Pili are a means of attachment.
True.
T/F: Axial Filaments are Appendages for means of attachment.
False, they are appendages for means of motility
What distinguishes prokaryotes from other bacteria?
It has a flagella.
What are the three parts of the flagella, and where are they located?
The Basal Body – the foundation: sits between cell wall and cell membrane. The Hook – sits above the cell wall surrounding the the filament. The Filament – inserts into the hook, and is able to move 360 degrees.
Name the two different types of arrangements of flagella.
The Polar Arrangement where flagella are attached at one or both ends of the cell. A peritrichous arrangement where flagella are dispersed randomly across the cell.
What are the three types of flagellate arrangements characteristic to polar arrangements and give a description of each?
Monotrichous arrangement – a single flagellum. Lophotrichous arrangement – small bundles of cells emerging from the same site. Amphitrichous arrangement – flagella at both poles of the cell
Define Run.
The linear, counterclockwise movement towards a stimulus.
Define tumble
The interruption of forward movement in a run to change the cell’s course.
Axial Filaments are characteristic of what type of bacteria only?
Spirochetes
Define and describe Axial filaments.
Axial filaments are bundles of fibrils that arise at the end of the cell beneath the outer sheath and spiral around the cell. The rotation of the filaments produces a spiral motion that propels the spirochete.
Define Fimbriae.
Hair like appendages, shorter than flagella, varying in number and distribution which contribute to attachment. Fimbriae enable the cell to adhere to surfaces, including surfaces of other cells – helping the microbe colonize.
Define Sex Pili.
Hair like appendages, shorter than flagella, longer than fimbriae numbering one or two per cell. They are primarily involved in conjugation.
True or False: Flagella are unique to spirochetes.
False, Axial filaments are unique to spirochetes. Flagella are unique to prokaryotes.
T/F: Fimbriae and Pili are longer than Flagella
False, they are shorter.
T/F: Lophotrichous arrangements of flagella are flagella located at both poles of the cell.
False, Lophotrichous arrangements are small bundles of flagella emerging from the same site. Amphitrichous arrangements are where flagella are located at both ends of the cell
T/F: A run is a clockwise linear movement towards a stimulus.
False, counterclockwise.
T/F: The filament moves 360 degrees around the hook.
False, it is inside the hook.
T/F: Monotrichous arrangements of flagella are a cell with a single flagellum, and are classified as a peritrichous arrangement.
False, they are classified as a polar arrangement – attached at one or both ends of the cell.
T/F: Endoflagella are bundles of fibrils beneath an outer sheath, spiraling around the cell.
True
Define Glycocalyx.
A coating which protects the cell, and sometimes allow it to adhere to its environment developing from macromoledules. It sometimes contains a slime layer to prevent nutrient and water loss, and sometimes contains a capsule composed of polysaccharide units and/or proteins contributing to its pathogenicity.
How do capsules make bacteria more virulent?
They protect the bacteria from phagocytosis, allowing them to multiply and infect body tissues.
What is the function of a cell wall?
To give protection, support, shape, and the prevention of cell rupture.
Gram Positive cell walls contain what layer(s) of their cell wall?
They contain one layer, the peptidoglycan layer composed of polypeptide chains (amino acids) and sugar. It is thick.
Gram Negative cell walls are composed of what layer(s) of their cell wall?
They contain two layers, the peptidoglycan layer, thinner than Gram Positive and the Lipopolysaccharide layer composed of a toxic endotoxin Lipid A, and O polysaccharide.
Why is it more difficult to treat a gram negative bacterial infection?
There are two layers.
Give examples of gram positive and gram negative bacteria types.
Gram Positive: Strep-, Staph-, bacillus subtilis, corynebacterium xerosis. Gram Negative: Proteus Vulgaris, E. Coli, Pseudomonas, Krypsillin pneumoniae, salmonella
Do all bacteria have cell walls?
Yes, save for a few exceptions.
The Glycocalyx and cell wall are part of what division of the prokaryotic cell?
The Cell envelope
True or False: Capsules make bacteria more virulent.
True, it allows them to escape phagocytosis.
T/F: Destroying a cell wall of a bacteria kills the bacteria.
True, cell walls prevent the cell from rupturing.
T/F: The peptidoglycan layer lies atop the cell membrane.
True
T/F: In the Glycocalyx, the slime layer protects the cell from water loss and nutrients.
True
T/F: The LPS is composed of lipids and polysaccharides.
True
Describe the four steps involved in the Gram Stain and the chemical reaction the bacteria goes under.
1 – Crystal violet is applied, and both take the dye, both turn purple. 2 – Gram’s Iodine is applied, and cyrstalizes the crystal violet in the case of the gram positive, and has no effect on gram negative. 3 – Alcohol is applied dissolving the crystal violet from the gram negative. The gram positive remains unaffected, continuing to be purple. 4 – Safranin dye is applied and the red dye stains the gram negative bacteria, turning them red. The crystals remain purple on the gram positive.
What is the counterstain in the Gram Stain process?
The safranin dye
What is the mordant in the Gram stain procedure?
Gram’s Iodine
True or False: The alcohol is called the dissolvent.
False, the decolorizer.
T/F: The primary dye is Crystal violet.
True
T/F: Certain types of cells have no cell walls or have very little cell wall material.
True, Mycoplasmas have no cell walls.
What are sterols?
Lipids found in the plasma membranes of mycoplasmas – they protect the cell from lysis (breakdown of lipids leading to cell rupture)
Define L-forms.
Cells which normally have cells but become wall deficients, losing them during their lifetime or by chemicals such as lysozyme or penicillin.
Define a spheroplast.
A Gram negative bacteria which has lost its Peptidoglycan layer due to the result of chemicals such as Penicillin or Lysozyme.
Describe the effects chemicals such as lysozyme or penicillin would have on a gram positive bacteria cell.
The Peptidoglycan layer would be dissolved and would become a Protoplast.
Mycoplasma Pneumoniae is an example of what?
A bacteria without a cell wall.
True or false: Lysis is the breakdown of lipids.
True
T/F: A sterol is a lipid thought to be found in Mycoplasmas
True
T/F: A Protoplast is a bacteria which has lost its Peptidoglycan layer yet has retained its Lipopolysaccharide layer
False, a protoplast is formed from Gram positive bacteria which have lost their Peptidoglycan layer. A Spheroblast retains the LPS, yet loses the peptidoglycan layer.
T/F: Lysozyme and penicillin can disrupt the structure of the cell wall.
True
What are Rickettsiae?
An Obligate intraceulluar parasite in animal cells, which cannot survive outside of its host cell and cannot carry out metabolism completely on its own. It is very tiny and gram negative.
How is Rickettsiae transmitted?
By arthropods, such as fleas, lice, or ticks. It alternates between a mammalian host and the arthropod
Name two diseases, their vector and agent of the disease.
Rocky mountain spotted fever is caused by the bacteria rickettsia rickettsii, and is transmitted by ticks. Typhus is caused by rickettsia prowazekii and is transmitted by lice.
What are Chlamydias? Give an example of a Chlamydia.
Very tiny gram negative bacteria which require host cells for growth and metabolism (obligate intracellular parasites). Chlamydia trachomatis is the cause of severe eye infection and is one of the most common STDs
What are Mycoplasmas? Give an example of one.
Extremely tiny bacteria which natually lack a cell wall, and are not obligate prasites. Their cell membrane is stabilized by sterols and is resistant to lysis. Mycoplasma Pneumoniae causes Primary Atypical Pneumonia in humans. It inhibits ciliary action, and thus causes the sloughing off of epithelia causing inflammation and other tissue damage.
True or False: Rickettsiae cannot survive outside their host cell.
True, they are obligate intracellular parasites.
T/F: Chlamydias are transmitted by arthropods.
False, they are not.
T/F: Mycoplasmas are gram positive bacteria.
False, it is neither – it has no cell wall.
T/F: Mcyoplasmas can be grown on artificial media.
True, they are not obligate intracellular parasites.
T/F: Typhus, caused by rickettsia rickettsii is an example of Rickettsiae.
False, it is caused by rickettsia prowazekii
T/F: Chlamydias and Rickettsiae are both very tiny gram negative bacteria.
True
T/F: Mycoplasmas are the smallest bacteria outside living cells.
True
T/F: The inhibition of ciliary action is the result of Chlamydia trachomatis.
False, Chlamydia trachomatis causes severe eye infection. Mycoplasma pneumoniae inhibits ciliary action
T/F: An example of a human disease caused by Rickettsiae is Rocky Mountain fever caused by ticks.
False, it is called Rocky Mountain spotted fever, and it is caused by the bacteria Rickettsia rickettsii
T/F: Mycoplasmas are bacteria which naturally lack a cell wall.
True
What is a cell membrane composed of?
Phospholipids organized in a lipid bi-layer.
Define hydrophylic.
Water Loving.
The Phospholipid consists of what two parts and what are the features of both.
A head which is hydrophylic (water flooded) composed of phosphate. And Two tails which are hydrophobic (fear of water) composed of fatty acids.
Define CD.
Clusters of Differentiation found on the outside of a cell.
True or False: In a cell membrane, the two layers of phospholipids have their tails pointing inward, and heads outward.
True
T/F: the head of a phospholipid is hydrophobic.
False, Hydrophylic.
T/F: The tails of a phospholipid are composed of fatty acids.
True
What type of DNA do bacteria have?
Circular DNA
Define Plasmid.
An additional chromosome which can be transferred by conjugation. This chromosome contains 5 to 90 genes and can make the cell produce a toxin, or provide resistance to antibiotics.
Define Nucleoid.
A cluster of DNA flowing in the cytoplasm.
What is the organelle responsible for protein synthesis? What are its subparts?
Ribosomes which can read genes and genetic info. Ribosomes are made of two subunits: protein and rRNA
How do antibodies manipulate ribosomes to kill bacteria?
Antibodies target ribosomes of bacteria to interfere with protein synthesis, thus killing the bacteria.
True or False: the genetic material in the cytoplasm is free flowing with no nuclear membrane.
True, it is called a nucleoid
T/F: Linear DNA is found in most bacteria.
False, circular DNA is found in bacteria
T/F: Bacteria have one chromosome, sometimes with a plasmid.
True
What is sporulation?
Endospore production by bacteria to produce a dormant stage of bacteria to withstand extreme conditions (heat, cold, etc.)
How many endospores do bacteria produce? And where are they formed in the cell?
One at the end, near the end, or in the middle.
What is the reason for sporulation?
When nutrients become depleted
What two genera produce endospores?
Bacillus and clostridium
Describe the process of sporulation.
1 – Spore septum begins to isolate newly replicated DNA and a small portion of cytoplasm. 2 – DNA is surrounded by septum. 3 – The forming endospore develops within the cell membrane. 4 – Peptidoglycan layer is formed around endospore. 5 – Spore coat forms. 6 – Endospore is released and the mother cell dies
True or False: An endospore is a dormant stage of bacteria.
True, to withstand extreme conditions
T/F: The two genera that produce endospores are Bacillus and corynebacterium
False, Bacillus and Clostridium
T/F: Sporulation increases the number of bacteria.
False
T/F: During sporulation, after the forming of the peptidoglycan layer around the spore, the next step is the formation of the LPS layer.
False, Bacillus and Clostridium are gram positive
Define Virus.
Noncellular agents of disease
What is a virus composed of?
A protein capsid and a nucleic acid.
What is the nucleic acid composed of?
DNA or RNA
What do viruses lack?
Enzymes for most metabolic processes. Machinery for synthesizing proteins (Do not have DNA, RNA and ribosomes for their production)
What is the protein capsid made of? What is its function?
Repeating protein subunits. The capsid encloses and protects the nucleic acid
Why are viruses not cells?
They are inert outside of host cell and active only inside host cells. They cannot produce proteins.
What is the relative size of a virus?
They are ultramicroscopic in size – between 20 and 1000 nm. An Electron microscope is necessary to view them.
True or False: All viruses cause disease
True
T/F: Viruses lack enzymes for all metabolic processes.
False, for most metabolic processes
T/F: Viruses contain ribosomes.
False, only DNA or RNA
T/F: Viruses are “a package of bad news.”
True
T/F: Viruses are obligate intracellular parasites.
True
What Nucleic acid does a Bacteriophage contain?
DNA
What do bacteriophages infect?
Bacteria
What are the five steps in the life cycle of a Bacteriophage?
1-Attachment 2-Penetration (and injection) 3-Biosynthesis 4-Maturation 5-Release
What is the Life cycle of the AIDS virus?
The Virus binds to CD4 on cell. Virus fuses with cell and releases RNA. Reverse Transcriptase makes a DNA copy of viral RNA. A second DNA strand is copied from the first. Virus DNA enters nucleus and inserts into cell’s chromosome. Virus DNA is transcribed into virus RNA, which moves into cytoplasm. Viral RNA is translated into viral proteins. The New virus buds off of the cell
What does HIV attack?
T cells with CD4 on their cell membrane
What is HIV composed of?
Two strands of RNA and an enzyme, Reverse Transcriptase, in addition to a protein capsid in a lipid envelope. It also has six spikes around the capsid
How does HIV take over our T-cells?
By inserting its Viral DNA, transcribed from its own RNA with the help of Reverse transcriptase, into the nucleus of the T cell changing the cell’s chromosomes to make new HIV strands of DNA. This is copied into RNA, which produces more Reverse Transcriptase which is then bundled up and budded off to attack another T cell.
How does a Bacteriophage take over a bacteria cell?
It injects its genetic material into the bacteria cell, which it then forms more viral units which mature, assemble and move out – killing its host.
True or False: HIV viruses contain one strand of RNA and Reverse transcriptase.
False, they contain two strands of RNA
T/F: Under normal conditions Transcription is a process which copies RNA into DNA.
False, DNA into RNA
T/F: HIV attacks all T-cells.
False, only the ones with CD4 on their cell membranes
T/F: In the life cycle of a Bacteriophage, Maturation comes directly after Penetration.
False, Biosynthesis occurs after penetration
T/F: In the life cycle of an HIV virus, after a second DNA strand is copied from the first strand of viral DNA it then copies itself into virus RNA, which then moves to the cytoplasm in search of ribosomes.
False, after DNA is copied it enters the cell’s nucleus and inserts into the cell’s chormosomes to create new strands of viral DNA to then be copied into RNA in search of ribosomes in the cytoplasm.
T/F: A Bacteriophage resembles a syringe.
True.
Define Viroid
A virus made only of RNA infecting only plants
Define Prion
A virus made only of proteins. Mad Cow disease is an example.
What are Protozoa?
Unicellular eukaryotic, heterotrophic organisms.
The life cycle of a protozoa rotates between what two stages?
A trophozoite – the motile, feeding and growing stage – and the Cyst – a resistant, dormant stage.
How do protozoa reproduce?
Asexually (mitosis) primarily, some by multiple fission (schizogony), or sexually
Define Schizogony.
Nucleus in cell divides many times, then is surrounded by portions of cytoplasm
What are the classifications of protozoa?
Sarcodina, flagellata, sporozoa, and ciliata
Most human parasites go through what three general stages
Infestation – the microbe is transmitted to the human host from a source such as soil, air, water, food, animals, or insects. The microbe invades and multiples in the host. The microbe leaves the host in large numbers by a specific means and, to survive, must find and enter a new host
Define Vector.
An animal that transmits infectious agents from one host to another
True or False: Protozoa are a large group – more thank 20,000 species.
True
T/F: Protozoa are classified according to their motility.
True
T/F: Sarcodina have no mode of transportation
False, Sarcodina move by pseudopods. Apicomplexa (Sporozoa) have no means of locomotion
T/F: A trophozoite is a motile, feedin gand growing stage.
True
T/F: After the microbe invades and multiplies in the host, the microbe leaves the host in large numbers by a specific means and, to survive, must find and enter a new host.
True
What parasite causes ameobic dysentery and ameobic hepatitis?
Entamoeba Hystolytica
Give the location, vector/transmission, key characteristics, and describe the life cycle of Entamoeba Hystolytica.
This parasite lives in the large intestine. It is transmitted by water and veggies infected with cysts. It divides by binary fission. During the trophozoite stage the parasite feeds on RBCs and tissue of the large intestine. It is asymptomatic when in the large intestine – symptoms arise when it spreads elsewhere in the body. During the dormant stage it becomes a cyst with four divided nuclei, which can resist the environment. The location of the nucleolus determines a parasitic or free-living ameoba – centrally located indicates a parasite. Symptoms arise when the lining of the large intestine is dissolved and dysentery commences: diarrhea, blood, and mucus in stool. In the liver (sometimes spleen), Ameobic hepatitis can develop.
What is the vector and class of trypansoma brucei gambiense?
The tsetse fly. It is a flagellate.
Give the life cycle and disease caused by trypanosoma brucei gambiense.
Life cycle begins when tsetse fly injects victim with 50k plus parasites. The parasite multiplies in the bloodstream and infests the liver, spleen and lymph nodes – enlarging them. Parasite moves to CNS, changes sleeping patterns and causes death and coma: African Sleeping Sickness.
What protozoa causes Chagas Disease primarily in Central America?
Trypanosoma Cruzi
Give the life cycle and vector of Trypanosoma Cruzi.
The vector is the Reduviid bug (the kissing bug) which bites the corner of a person’s mouth, and defecates. When rubbed the person has inoculated themselves. The parasites multiply and infest muscle cells, primarily of the heart.
Give the vector and disease caused by Leishmania Tropica and Leishmania donovani.
The vector is the Sand fly. Leishmania tropica causes Oriental Sores, and Leishmania donovani causes Kala-azar
Give the life cycle of both leishmania tropica and donovani.
The sand fly bites and injects parasites with flagella into bloodstream. They lose their flagella when they enter macrophages. They multiply within the flagella, and depending on the parasite cause different diseases. Leishmania Tropica infects macrophages localized in the capillaries of the skin causing boils: Oriental Sore Leishmania Donovani causes black fever by infecting macrophages of the liver or spleen.
Traveller’s Disease is caused by what protozoa, and how is it transmitted?
Caused by Giardia lamblia from drinking water in nature.
Describe the appearance and life cycle of giardia lamblia.
Fiardia lamblia have two nuclei within two discs, and 8 flagella – resembles a face. The trophozoite lives in the intesinte and there is no vector. It becomes a cyst outside of the body residing in water.
True or False: The vector of Entamoeba Hystolitica are ameobas from pond water.
False, there is no vector.
T/F: Trypanosoma brucei gambiense feeds on RBCs and tissue of large intestine.
False, Trpanosoma brucei gambiense infests the liver, spleen and lymph nodes. Entamoeba Hystolytica feeds on RBCs and tissue of large intestine.
T/F: Trpanosoma brucei gambiense, Trpanosoma Cruzi, Leishmania tropica, Leishmania donovani, and Giardia Lamblia are all flagellates.
True
T/F: the vector of Leishmania tropica and donovani is the Phlebotomus fly.
True
T/F: Traveller’s Disease is caused by Entamoeba Hystolitica.
False, it is caused by Giardia lamblia
T/F: Entamoeba Hystolitica causes several symptoms during its trophozoite stage in the large intestine.
False, only when it spreads to the liver, or when it dissolves the intestinal lining causing dysentery.
T/F: In the nucleus of a parasitic Entamoeba Hystolitica the nucleolus is centrally located.
True
T/F: Trpansoma brucei gambiense has two cures: one toxic, one less toxic. This cure is readily available to Central Africa.
False, it is far too expensive.
T/F: There is no vector of Trpanosoma Cruzi.
False, it is the Reduviid Bug (The Kissing Bug).
T/F: Leishmania donovani causes Oriental Sore
False, it causes Kala-azar. Leishmania tropica causes Oriental sore.
T/F: The transmission of Entamoeba Hystolytica and Giardia lamblia is through drinking water.
True
What is the specific vector of Malaria, and what protozoa is responsible?
The Anopheles genus of mosquito is responsible for harvesting the sporozoites of Plasmodium Falciparum
What are the three phases of the life cycle of Plasmodium Falciparum?
Injection of the parasite by mosquito. Asexual phase – carried out in humans. Sexual phase – carried out in mosquitos
Describe the Asexual phase of Plasmodium Falciparum.
Two parts: Exoerythrocytic and Endoerythrocytic. The exoerythrocytic stage happens outsid eof RBCs – taking place in liver cells at a period of incubation. The number of parasites increases by schizogony – the host feels no symptoms. The liver cells rupture releasing new parasites: 2000 or more. The Endoerythrocytic cycle takes place within RBCs. Merozoites are the motile parasites traveling to these RBCs. During the Ring Stage, the parasites is converted within the cell, it digests the hemoglobin, where the byproduct is melanin. The parasite then divides by multiple fission forming more parasites within the cell. The cell ruptures releasing the melanin and parasites into the bloodstream. The parasites form male and female gametes and are then drawn up by a mosquito where the sexual phase takes place.
Describe the sexual phase of Plasmodium falciparum
The sexual phase is completed in the intestine of the mosquito, which cannot digest the gametes. Here the gametes reproduce forming zygotes. The zygote forms an oocyst which moves into the stomach and undergoes multiple fission. It then forms thousands of sporozoites which move to the salivary glands of the mosquito ready to move on out to a new victim of the mosquito.
Describe the life cycle of trichomonas vaginalis.
Trichomonas vaginalis is transmitted by direct contact between membranes, and cannot survive outside a living host. There is no cyst stage – there is also no vector – it dies after the trophozoite stage. This protozoa is mostly asymptomatic but when aggressive can cause vaginitis in females (frequent urination, pain, yellow discharge), and in males: urethritis, and infection of the prostate gland.
Describe the physical characteristics, causative disease, transmission and life cycle of Balantidium Coli.
Balantidium Coli has contractile vacuoles which get rid of excess water, maintaining osmotic pressure. It causes severe diarrhea and lives in the colon of large intestine. It is transmitted to pig handlers through infected water and food. Balantidium Coli reproduces by binary fission and sexually reproduces – conjugation: the exchange of genetic materials.
Describe the life cycle of Toxoplasma Gondii.
Primarily found in cats, it has two phases: the asexual phase within the cat, and the sexual phase within the intestine of cat. During the asexual phase the Toxoplasma Gondii ingested from soil of food is called a trochozoite. A pseudocyst forms from the trochozoite, and is found in the muscle tissues of the cat. During the sexual phase an oocyte is released by the cat into the soil.
Define opportunistic.
Parasite becomes aggressive with a being with a weak immune system
What causes the symptoms of malaria?
The rupturing of RBCs containing melanin
True or False: Plasmodium Falciparum is the most malignant form of malaria.
True
T/F: Merozoites are male and female gametes ingested by a mosquito.
False, they are exoerythrocytic parasites motile and on their way to RBCs
T/F: Balantidium Coli is transmitted by direct contact between membranes.
False, Balantidium Coli is transmitted by food and water, especially by pig handlers. Trichomonoas vaginalis is transmitted by direct contact between membranes
T/F: Toxoplasma gondii primarily uses cats for its life cycle.
True
T/F: Toxoplasma gondii are opportunistic.
True
T/F: Trichomonas vaginalis cannot survive outside of living host
True
T/F: Balantidium Coli is dangerous to pregnant women.
False, Balantidium Coli causes severe diarrhea. Toxoplasma gondii is dangerous to pregnant women – toxoplasmosis can occur.
T/F: Balandtidium coli is found in individuals who handle cats.
False, it is found high in individuals who handle pigs. Toxoplasma gondii is found in cats.
T/F: The Plasmodium falciparum lives out its sexual phase carried out in mosquitos.
True
T/F: the reason for malaria is because Anopheles mosquitos cannot digest the sporozoites of plasmodium falciparum.
False, they cannot digest the gametocytes of plasmodium falciparum
T/F: Trichomonas Vaginalis has no vector
True
T/F: Transverse division in paramecium is where one individual splits to become two.
True
T/F: A speudocyst forms from a trochozoite during the Sexual phase of Tocoplasma gondii.
False, the Asexual phase.
T/F: Chagas Disease is caused by Giardia Lamblia
False, it is caused by Trypanosoma cruzi
T/F: Malaria is caused by Mycobacterium Pneumoniae.
False, it is caused by Plasmodium falciparum
T/F: Trichomonas vaginalis causes vaginitis.
True
T/F: Leishmania tropica causes oriental sore
True
T/F: Giardia lamblia cuases diarrhea
True
T/F: Dum-dum fever is caused by Trpanosoma brucei gambiense.
False, Leishmania donovani causes dum-dum fever. Trypanosoma brucei gambiense causes African sleeping sickness.
T/F: Dysentery is caused by Toxoplasma gondii
False, Dysentery is caused by Entamoeba hystolytica. Toxoplasma gondii causes Toxoplasmosis.
How do fungi reproduce?
By budding or pseudohypha. Budding is where a bud develops and breaks off of mother cell with exact DNA replication. Pseudohyphae are where buds remain attached to mother cell and do not separate
What is mycology?
The study of fungi
What two basic forms do microscopic fungi exist in?
Yeasts and Hyphae
Define Yeast.
A nonfilamentous, unicellular fungi which is typically spherical or oval.
Define Hyphae.
Long filaments found in the bodies of molds.
What are the two different types of hyphae?
Septate hyphae – hyphae which containe cross walss called septa which divide them into uninucleate cell-like units. Coenocytic hyphae – when hyphae contain no septa and appear as continuous cells with many nuclei
What is it called when hyphae grow to form a filamentous mass?
Mycelium
Define fungi.
Eukaryotic, heterotrophic organisms which obtain their nutrients from remnants of dead plants and animals (saprobes)
What are the four phyla of fungi?
Zygomycota, Ascomycota, Basidiomycota and Deuteromycota
What is a substrate, and how do fungi use it?
A substrate is a target substance where fungi secrete enzymes and nutrients are then absorbed. This is done this way since fungi digest extracellularly.
What are the two types of spore formation and what cell division process accompanies each?
Asexual spores are the product of mitosis and sexual spores are formed through a process involving the fusing of two parental nuclei followed by meiosis.
True or False: Male and Female are used to designate opposing parent cells during sexual reproduction.
False, they are designated as positive or negative parent cells.
T/F: Parasitic fungi can use the bodies of living plants and animals as substrates.
True
T/F: Hyphae are long filaments found in the bodies of molds.
True
T/F: Meiosis is the reduction of chromosome number
True
T/F: Digestion is extracellular in fungi
True
T/F: Microscopic fungi exist in three forms.
False, two: yeasts and hyphae
T/F: Apicomplexa is a phyla of fungi.
False, the phyla are ascomycota, zygomycota, Deuteromycota and Basidiomycota.
Define Sporangium.
A ball of spores which produces more spores.
Give the life cycle of Rhizopus
Asexual Phase – mother cells form asexual spores in sporangia (through mitosis) which germinate and form hyphae. Sexual phase – two hyphae come together, their cells joining together forming a zygote to form a sporangium (through meiosis). The sporangium produces sexual spores.
Give an example of ascomycota and the growing characteristics of it.
Candida Albicans is opportunistic and is the cause of vaginitis and thrush in newborns. Antibiotics can stimulate its growth by lowering the pH level in the vagina. The increase in glucose also stimulates growth.
Meningitis is caused by what fungi?
Cryptococcus neoformans
What is the portal of entry and life cycle of cryptococcus neoformans?
The portal of entry is the respiratory system, where the fungus grows in the lungs. It gains access to the bloodstream when the immune system is weak. It travels to the CNS causing meningitis.
Coccidiodes minitis causes what disease?
Valley Fever, San Joaquin Fever
What is the portal of entry and life cycle of Coccidioides minitis?
The portal of entry is in the respiratory system of humans. It forms a sphenule in the lungs, and forms endospores which infect lung tissues causing pain, cough, headache and fever.
Define arthrospores.
Spores which form between joints of hyphae.
How is Coccidioides minitis spread?
By dust and wind – the arthrospores germinate in soil.
Define Lichen
Symbiotic relationship between fungi and algae
Define Mycorrhizae.
Symbiotic association between roots of plants and fungi.
True or False: Antibiotics can stimulate the growth of candida albicans.
True
T/F: Cryptococcus neoformans has a capsule.
True
T/F: During the sexual phase of Rhizopus, the mother cells from asexual spores in sporangia germinate and form hyphae through mitosis.
False, the sexual phase involves two hyphae coming together to form a zygote, in turn forming a sporangium which produces sexual spores.
T/F: Fungi grow at a lower pH than bacteria.
True.
T/F: Fungal diseases require a longer treatment period than most bacteria.
True
T/F: San Joaquin Fever is caused by the fungus Aspergillus flavus.
False, caused by Coccidioides minitis
T/F: Arthrospores form along hyphae.
False, between joints of hyphae
T/F: Lichens are symbiotic associations between fungi and algae.
False, they are symbiotic relationships between plants and fungi.

Deck Info

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