Microbiology Lab Test 3

Front 1

Name four distinguishing characteristics of protozoa.

Back 1

1. absence of a cell wall
2. ability to move by locomotor organelles or gliding system during all or part of their life cycle
3. heterotrophic
4. primarily asexual

Front 2

Classes of protozoa are separated by what characteristic?

Back 2

Means of locomotion

Front 3

Name the four classes of protozoa.

Back 3

1. Sarcodina
2. Mastigophora
3. Ciliophora
4. Sporozoa

Front 4

What means of locomotion do the sarcodina class of protozoa use?

Back 4

Pseudopods resulting from the streaming of ectoplasm

Front 5

What means of locomotion do the mastigophora class of protozoa use?

Back 5

One or more whiplike, thin structures called flagella

Front 6

What means of locomotion do the Ciliophora class of protozoans use?

Back 6

Short hairlike projections called cilia

Front 7

What means of locomotion do the sporozoa class of protozoans use?

Back 7

Only immature members have locomotor organelles; these organelles vary between species

Front 8

Which class of protozoa only have parasitic species?

Back 8

Sporozoa

Front 9

Give a(n) example(s) of both free-living and parasitic species of the protozoan class sarcodina.

Back 9

Free-living: Amoeba proteus
Parasitic: Entamoeba histolytica

Front 10

Give a(n) example(s) of free-living genera and parasitic species of the protozoan class mastigophora.

Back 10

Free-living: (genera) Cercomonas, Heteronema, and Wuglena
Parasitic: (species) Trichomonas vaginalis, Giardia lamblia, and Trypanosoma

Front 11

Give a(n) example(s) of both free-living and parasitic species of the protozoan class ciliophora.

Back 11

Free living: Paramecium caudatum
Parasitic: Balantidium coli

Front 12

Which protozoan parasites do not require an intermediate host?

Back 12

Entamoeba histolytica, Balantidium coli, and Giardia lamblia

Front 13

Name the parasitic protozoan of the class Sarcodina that causes amebic dysentery. Upon integestion of this organism, the mature quadrinulceated cyst wall disintegrates and the nuclei divide, producing eight active trophozites (metabolically active cells) that move to the colon, where they establish infection.

Back 13

Entamoeba histolytica

Front 14

This ciliated parasitic protozoan exhibits a life cycle similar to that of E. histolytica except that no multiplication occurs within the cyst. It resides primarily in the lumen and submucosa of the large intestine causing intestinal ulceration and alternating constipation and diarrhea.

Back 14

Balantidium coli

Front 15

This parisitic protozoan flagellate is responsible for the induction of abdominal discomfort and severe diarrhea. Diagnosis is made by finding cysts in the formed stool and both cysts and trophozoites in the diarrhetic stool.

Back 15

Giardia lamblia

Front 16

Name the mastigophoric hemoflagellate responsible for various forms of African sleeping sickness.

Back 16

Trypanosoma

Front 17

What is required for the Trypanosoma to complete its cyclic development?

Back 17

Two hosts: a vertebrate host and an invertebrate, blood-sucking insect host

Front 18

Which class of protozoa demonstrate the greatest degree of cyclic complexity?

Back 18

Sporozoa (composed of exclusively obligate parasitic forms)

Front 19

Which genus of Sporozoa is responsible for malaria in both humans and animals?

Back 19

Plasmodium

Front 20

Which two hosts does a Plasmodium require to complete its life cycle? Which is the definitive host?

Back 20

Human and female Anopheles mosquito; female Anopheles mosquito is the definitive host

Front 21

What happens after a human is bitten my a mosquito infected by one of the Plasmodium species.

Back 21

The parasites pass rapidly from the blood to the liver, where the infect the parenchymal cells (pre-erythrocytic stage). There they develop asexually by a process called schizogony, producing merozoites. Merozoites are released from the ruptured liver cells and cell infect red blood cells (erythrocytic stage).

Front 22

Name the morphological forms that a species of the Plasmodium genus go through during their asexual development. (6)

Back 22

Signet rings, trophozoites, schizonts, segmenters, merozoites, and gametocytes.
(SIGmonds TROPHy Shows Shiny Monkeys and Gorillas)

Front 23

Which asexual form of the Trypanosoma species is capable of infecting other blood cells or liver cells?

Back 23

Merozoites

Front 24

How is the life cycle of the Trypanosoma species completed?

Back 24

Ingestion of the microgametes (male) and macrogametocytes (female) by another mosquito during a blood meal initiates the sexual cycle called sporogamy. Male and female gametes five rise to a zygote in the insects gut which is transformed into an ookinete that burrows through the gut wall to form an oocyst in which the sexually mature sporozoites develop.

Front 25

Distinguish between the pre-erythrocytic and erythrocytic stages of the malarial parasite.

Back 25

Pre-erythrocytic stage occurs in the liver, this is where the parasite develops asexually producing merozoites. Erythrocytic stage occurs when the merozoites infect the blood cells and goes through a series of morphological stages.

Front 26

What is the branch of microbiology that deals with the study of fungi (yeast and molds)?

Back 26

Mycology

Front 27

Name the four classes of true fungi.

Back 27

1. Zygomycetes
2. Ascomycetes
3. Basidiomycetes
4. Deuteromycetes (aka Fungi Imperfecti)

Front 28

What characteristic is used to separate classes of fungi?

Back 28

Their sexual modes of reproduction

Front 29

Why is the Deutoromycete class also know as Fungi Imperfecti?

Back 29

No sexual reproductive phase has been observed

Front 30

Describe the sexual spores of Zygomycetes.

Back 30

External and uncovered

Front 31

Which types of molds are included in the zygomycete class?

Back 31

Water, bread, and terrestrial molds

Front 32

Describe the sexual spores of Ascomycetes.

Back 32

Sexual spores, called ascospores, are produced in a saclike structure called an ascus

Front 33

What is included in the class ascomycetes?

Back 33

Yeasts and molds

Front 34

Describe the sexual spores of basidiospores?

Back 34

The reproductive spores, called basidiospores, are separate from specialized stalks called basidia

Front 35

What are included in the class basidiomycete?

Back 35

Fleshy fungi, toadstools, mushrooms, puffballs, and bracket fungi

Front 36

True or false?
Fungi are limited to metabolizing a limited number of organic substrates.

Back 36

False.
They can metabolize a wide variety of organic substrates.

Front 37

Are fungi heterotrophic or autotrophic?

Back 37

Heterotrophic

Front 38

Name some of the ways fungi are a benefit to humans.

Back 38

They play a vital role in decomposing dead animal and plant tissue maintaining fertile soil. They can also be used industrially to produce beer, wine, bakery products, cheeses, antibiotics, among other things.

Front 39

Which class do most of the pathogenic fungi belong to?

Back 39

Deuteromycetes

Front 40

Name the two groups of pathogenic Deuteromycetes and the areas that they infect.

Back 40

Superficial mycoses; cause infections of the skin, hair, and nails (ex: ringworm infections)
Systemic mycoses: cause infections of the subcutaneous and deeper tissues such as the lungs, genital areas and nervous system

Front 41

Name the only class of fungi that has nonseptate mycelium.

Back 41

Zygomycetes

Front 42

What are the major fungal organisms that can be seen by the naked eye?

Back 42

Molds

Front 43

An "intertwining branching mat" is used to describe what?

Back 43

Mycelium

Front 44

What are the filaments that make up the mycelial mat called?

Back 44

Hyphae

Front 45

What is vegetative mycelium?

Back 45

When most of the mycelium mat grow on or in the surface of the nutrient medium.

Front 46

What is aerial mycelium?

Back 46

When the mycelium mat grows upward from the mat.

Front 47

What type of media is needed to grow molds?

Back 47

Selective media such as Sabouraud agar or potato dextrose agar

Front 48

What is it about the Sabouraud agar and potato agar that facilitate mold growth?

Back 48

Their low acidity (pH 4.5 ti 5.6)

Front 49

What temperatures do most molds grow at?

Back 49

Room temperature (25 degrees C)

Front 50

What is advantageous about observing mold colonies on an agar plate?

Back 50

It allows you to observe the variations of gross colonial morphology which plays a major role in the identification of the filamentous fungi

Front 51

What is yeast?

Back 51

Nonfilamentous, unicellular fungi

Front 52

How does the size of yeast compare to bacteria?

Back 52

Yeasts are 5-10 times larger

Front 53

How does yeast reproduce?

Back 53

Asexually by budding or by fission; also sexually

Front 54

Name some ways in which yeasts are important to humans.

Back 54

They are used as leavening agents in dough, for brewing, fermentation of grape juice and their high vitamin content makes them valuable as food supplements

Front 55

Which yeast is responsible for urinary tract and vaginal infections and infections of the mouth?

Back 55

Candida albicans

Front 56

What are urinary tract and vaginal infections that are caused by Candida albicans called?

Back 56

Moniliasis

Front 57

What are infections of the mouth caused by Candida albicans called?

Back 57

Thrush

Front 58

What are the significance of buds in the reproductive activities of yeast cells?

Back 58

A bud is an outgrowth from the parent cell that pinches off during budding, a form of asexual reproduction

Front 59

What is the significance of an ascospores in the reproductive activities of yeast cells?

Back 59

During sexual reproduction two sexual spores conjugate, giving rise to a zygote (diploid cell) which then divides by meiosis producing four new haploid nuclei which are sexual spores called ascospores

Front 60

What is the significance of an ascus in the reproductive activities of yeast cells?

Back 60

The ascus contains the ascospores; it will rupture and release the ascospores allowing them to conjugate, starting the cycle over again

Front 61

What can be used to identify different genera of yeasts?

Back 61

Cultural characteristics, type of reproduction, and the fermentative activities

Front 62

Because of their limited and simplistic structure how are viruses chemically defined?

Back 62

Nucleoproteins

Front 63

What is needed in order to view a virus?

Back 63

An electron microscope

Front 64

What are bacterial viruses called?

Back 64

Bacteriophages, or just phages

Front 65

List the five sequential events involved in phage infection.

Back 65

1. Adsorption 2. Penetration
3. Replication 4. Maturation
5. Release

Front 66

What happens during the adsorption phase?

Back 66

Tail fibers of the phage particle bind to receptor sites on the host's cell wall

Front 67

What happens during the penetration phase?

Back 67

Spiral protein sheath retracts and an enzyme, early muramidase, perforates the bacterial cell wall enabling the phage nucleic acid to pass through the hollow core into the host cell's cytoplasm

Front 68

What happens during the replication phase?

Back 68

The phage genome subverts the cell's synthetic machinery, which is then used for the production of new phage components

Front 69

What happens during the maturation phase?

Back 69

New phage components are assembled and form complete, mature virulent phage particles

Front 70

What happens during the release phase? (Virulent phage)

Back 70

Late muramidase (lysozyme) lyses the cell wall, liberating infectious phage particles that are now capable of infecting new susceptible host cells

Front 71

How is temperate phage different from a virulent phage?

Back 71

The infected host cell continues to function as normal until exogenous physical agents such as ultraviolet, ionizing radiation, or chemical mutagenic agents induces lysis

Front 72

What are the bacterial host cells that have the temperate phage's nucleic acid incorporated in it called?

Back 72

Lysogenic cells

Front 73

How do animal viruses differ from bacteriophages?

Back 73

They lack the spiral protein sheath, base plate and tail fibers; their shapes are helical or cuboidal

Front 74

Why are some animal viruses designated as "naked viruses"?

Back 74

Because they are composed soley of nucleocapsids

Front 75

What are enveloped viruses?

Back 75

Their nucleocapsid is surrounded by a lipid bylayer that may have glycoproteins associated with it

Front 76

How does adsorption differ in an animal host from a bacterial host?

Back 76

Adsorption occurs to receptor sites that are located on the cell membrane of the host cell instead of the cell wall as in the bacterial host

Front 77

How does pentetration differ in an animal host from a bacterial host?

Back 77

Penetration is accomplished by endocytosis in an animal host, the entire virus enters the host cell; in bacteria only the enzyme, early muramidase, goes through the cell wall

Front 78

What is required for endocytosis to occur in an animal host cell?

Back 78

Energy and compliment receptor site

Front 79

How is the latent period different in an infected bacterial cell from an infected animal cell?

Back 79

The latent period in an infected bacterial cell is much shorter; minutes vs. hours or days