Chapter 5 – Microbiology Test Questions – Flashcards
Unlock all answers in this set
Unlock answers| How were eukaryotic cells evolved? |
Through symbiosis (large prokaryotic cell engulfed smaller bacterial cells that began to live and reproduce inside prokaryotic cell rather than being destroyed)
First primative cell was probably single-celled and independent. Eventually formed colonies that became specialized and evolved into multicellular organisms. |
| Which eukaryotic organism is always unicellular? |
| protozoa |
| Which eukaryotic organisms may be unicellular or multicellular? |
Fungi Algae |
| Which eukaryotic organism is always multicellular? |
Helminths (have unicellular eggs or larval forms) |
| How are eukaryotic flagella different from prokaryotic flagella? |
10x thicker Structurally more complex Covered by an extension of the cell membrane |
| What's the arrangement of microtubules in euk. flagella? How does it move? |
9+2 arrangement (9 outside, 2 in middle) ; Whip-like movement (not runs and tumbles) |
| What are cilia? |
Shorter locomotor appendages that are more numerous. ; Also function as feeding and filtering structures |
| Describe the glycocalyx and its functions. |
Appears as network of fibers, a slime layer, or a capsule. ; They both function as protection, adhesion, and reception of signals. |
| Identify the variations of the layer beneath the glycocalyx. |
Fungi and most algae have a thick, rigid cell wall ; Protozoa and animal cells do not have a cell wall |
| What makes up the cell wall of fungi? |
Thick inner layer of chitin or cellulose ; Thin outer layer of mixed glycans |
| What makes up the cell wall of algae? |
| Varies- may contain cellulose, pectin, mannans, and minerals |
| What makes up the cytoplasmic membrane of a eukaryotic cell? |
| Phospholipid bilayer with embedded protein molecules. Also contains sterols, which gives it stability. Sterols are important in cells without a cell wall. |
| What are three unique things about eukaryotic mitochondria? |
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| What do chloroplasts do? What do they have that's unique? |
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| What's the S count for eukaryotic ribosomes? Why is this important for medicine? |
80S ; We can use drugs to affect 70S ribosomes of prokaryotic cells without affecting 80S ribosomes of eukaryotic cells. The drugs would however affect the ribosomes of the mitochondria and the chloroplasts of eukaryotic cells. |
| What are the two types of cytoskeleton elements? |
| Microfilaments and microtubules |
| What two groups can Fungi (myceteae) be divided into? Give examples of each. |
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| What distinguishes a yeast cell? |
| Its round shape and its mode of asexual reproduction (buds) |
| What makes up a mold? How are they classified? |
Hyphae- long, threadlike cells ; Septate (segmented surface) or nonseptate (smooth surface) |
| What's a dimorphic fungi? |
| A fungi that can take either the form of yeast or the form of hyphae depending upon growth conditions, such as changing temperature. |
| What is a mycelium? |
| The woven, intertwining mass of hyphae that makes up the body of colony of a mold |
| What's a pseudohypha? |
| A chain of yeasts formed when buds remain attached in a row and look like hyphae but are not. |
All fungi are heterotrophic. True or False? |
| True- they acquire nutrients from organic materials called substrates |
Few fungi are saprobes. True or False? |
| False- most are saprobes. They obtain their substrates from the remnants of dead organisms in soil or aquatic habitats |
Few fungi are parasites. True or False? |
| True- Parasites are on the bodies of living animals or plants. |
| What's the useful yeast identified in class? |
| Saccharomyces (makes beer, wine) |
| What are two pathogenic fungi identified in class? |
Cryptococcus Candida |
| What's the name of fungal reproductive bodies? |
Spores |
| What are the two subtypes of asexual spores? Describe them. |
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Sexual spores are produced by most fungi at some point. True or False? |
| True |
| What's a protist? What two subkingdoms does it contain? |
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| Describe algae. |
| Photosynthetic protists that are unicelluar, colonial, and filamentous in forms. They also have larger forms that possess tissues and simple organs. |
Algae contain all eukaryotic organelles. True or False? |
| True |
Algae are one of the main components of plankton. True or false? |
| true |
| Algae are rarely infectious but one of their primary medical threats includes... |
| Shellfish exposed to red tide (food poisoning) |
| Which eukaryotic organelle do protozoa lack? |
| chloroplasts |
| How is protozoal cytoplasm divided? |
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Some protozoa have organelles that work like a primitive nervous system. True or false? |
| True- ciliates and flagellates |
| Do protozoa have a cell wall? |
| No- This allows for some flexibility. Cell shape can remain constant or change constantly (such as amoebas) |
| Protozoa are heterotrophic. What are some ways they get their nutrition? |
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| What are the predominant habitats of protozoa? |
fresh and marine water soil plants animals
**main limiting factor is the availability of water** |
| What's the dormant stage of a protozoa called? |
| A cyst |
| All protozoa but the Apicomplexa are motile. What three means do they move by? |
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| What's the trophozoite stage of protozoa? |
| The vegetative stage- require ample food and moisture to stay active |
| What determines the life cycle of a parasitic protozoan? |
| the mode of transmission to the host |
All protozoa reproduce by asexual methods. True or False? |
| True- most also reproduce with sexual reproduction like through conjugation with their cilia |
| What are the 4 classifications of medically important protozoa? |
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| Describe mastigophora (flagellated) protozoa. |
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| What are examples of Mastigophora (flagellated) and why are they important medically? (4) |
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| Describe Sarcodina (amoebas) protozoa. |
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| What's an example of a sarcodina (amoeba) protozoa that's medically important? Why? (1) |
Entamoeba
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| Describe Ciliophora (Ciliated) protozoa. |
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| Describe Apicomplexa (Sporozoa) protozoa. |
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| What are 2 diseases caused by Apicomplexa (Sporozoa) protozoa? |
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| What are parasitic helminths? When do you need a microscope with them? |
Tapeworms, flatworms, roundworms
Microscope is necessary to ID eggs and larvae |
| Describe flatworms. |
Thin and often segmented.
In the phylum Platyhelminthes
Asexual or sexual reproduction. |
| What are the two subdivisions of flatworms? Give examples of each. |
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| Describe roundworms. |
AKA nematodes
elongated and cylindrical unsegmented
phylum Aschelminthes |
| Describe general characteristics of helminths. |
Most developed organ are those of the reproductive tract
Some degree of reduction in digestive, excretory, nervous, and muscular systems
Most have thick cuticles for protection and mouth glands for break down the host's tissue |
| Describe the helminth cycle, as based upon the pinworm. |
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