Chapter 12 Flashcards
What crop famine resulted from the water mold Phytophthroa infestans from 1845 to 1847?
Irish Potato Famine
In the Irish Potato Famine, how was Phytophthroa infestans transmitted?
Transmitted by spores that can persist in soil.
What are the four groups of microscopic eukaryotes that we learn in this class?
Algae, Fungi, Protozoa, and Protists
What are the three main structural differences between microscopic eukaryotes versus prokaryotes?
Membrane-bound organelles, no peptidoglycan layer, and usually well-developed cytoskeleton.
Microscopic eukaryotes undergo asexual reproduction via _______ and sexual reproduction via ________.
Mitosis, Meiosis
T/F: Microscopic eukaryotes can be haploid and/or diploid.
True
What are the three steps of meiosis in microscopic eukaryotes?
- Diploid cells produce haploid cells.
- Can develop into haploid organisms or gametes (sex cells).
- Fusion of two gametes forms diploid cell; recombination of genetic material.
Fungi consists of what three major groups?
Molds, Yeasts, Mushrooms
What is the study of fungi known as?
Mycology
Molds, yeasts, and mushrooms refer to the ________________, not classification.
Morphological Forms
Yeasts are _________ fungi.
Molds are ________ fungi.
Mushrooms are _________ of certain fungi.
Single-Celled
Filamentous
Reproductive Structures
In fungi, the cell wall usually contains what unique material? What is the unique material in fungal membranes?
Chitin
Ergosterol
What two groups are the main decomposers on Earth?
Fungi and Bacteria
What does Saprophytic mean in regards to fungi?
Obtain nutrients from dead or decaying matter.
Fungi decompose materials by _____________ to break up large molecules.
Secreting Enzymes
What two unique materials are fungi able to decompose?
Cellulose and Lignin (Wood)
What are the two byproducts of fungi decomposition?
Release CO2
Release nitrogen compounds into soils.
Name one fungi that forms symbiotic relationships.
Lichens
Are plants or animals mainly targeted by fungi that act as parasites of living tissue?
Plant infections common, few infect humans.
What is another name for Ascomycetes?
Sac Fungi
What group of fungi comprises approximately 75% of known fungi?
Ascomycetes
Penicillium, lichens, morels and truffles, and pathogens (Dutch Elm disease) belong to what subclass of fungi?
Ascomycetes
What is another name for Basidiomycetes? What are they known for?
Club Fungi
Reproduce with mushrooms
Plant parasites, such as smuts and rusts, belong to what subclass of fungi?
Basidiomycetes
What subclass of fungi does black bread mold (Rhizopus) belong to?
Zygomycetes
What is the main difference between Zygomycetes compared to other subclasses of fungi?
Use reproductive structures called sporangia.
What are the two environments where Chytrids can be found?
Usually live in water
Some live in mammalian gut
In the Chytrid subclass of fungi, Batrachochytrium dendrobatidis is known for infecting what animal?
Frogs
What is the only subclass of fungi that are motile (reproductive cells have flagella)?
Chytrids
Most fungi are multicellular molds that are composed of thread-like _______.
Hyphae
What is a visible mass of hyphae called?
Mycelium
What is the purpose of the high surface-to-volume ratio of mycelium?
Aids in nutrient absorption
What is the purpose of enzymes repelling other hyphae?
Efficient nutrient distribution and preventing competition within the same mycelium.
Hyphae grow at the tips and in the direction of _________.
Food Source
Are fungi most successful in moist or dry environments?
Moist
_________ and __________ fungi have specialized hyphae.
Parasitic and Saprophytic
In parasitic fungi, specialized hyphae called ________ protrude into host cells.
Haustoria
In saprophytic fungi, specialized hyphae called _______ may anchor to substrate.
Rhizoids
___________ fungi can grow as single yeast cells or multicellular hyphae.
Dimorphic
Since Histoplasma capsulate is a mold in soil and produces reproductive spores that are easily airborne, it is known as what term? How can it cause disease?
Dimorphic.
Develops into yeast form when inhaled.
Fungi is mostly ________, but can be found everywhere including thermal pools, volcanic craters, and high salt environments.
Terrestrial
T/F: All fungi can grow on all materials.
False. Some are widespread, others grow on a specific plant.
What special compound can be unexpectedly degraded by fungi?
Plastic
What is the main difference between the environments that fungi can grow in compared to bacteria?
Fungi can grow in salts, sugars, and acids that inhibit bacteria.
T/F: Most fungi prefer 20 degrees to 35 degrees Celsius, but easily survive lower temperatures (some grow below freezing).
True
Are most fungi aerobic or anaerobic?
Aerobic
While the majority of fungi are aerobic, some yeasts are facultative anaerobes that produce what byproduct?
Ethanol
While the majority of fungi are aerobic, some obligate anaerobes can be found in the rumen of ______.
Cows
________ are association/blend of fungus and photosynthesizer (alga or cyanobacterium).
Lichens
Lichens are a good indicator of ________.
Air Quality
What is special about the environment that lichens are found in?
Grow in ecosystem where neither partner could survive alone. For example, subarctic tundra or bare rock.
What is the function of both the fungus and photosynthesizer components of lichen?
Fungus protects and absorbs water and minerals. Photosynthetic member provides organic nutrients.
What has a beneficial association with plant roots?
Mychorrhizas
What estimated percentage of vascular plants have mycorrhizas?
80%
What is one type of plant that requires mycorrhizas?
Orchids
In the symbiotic relationship of mycorrhizas, the plant supplies the fungus with what?
Organic Compounds
In the symbiotic relationship of mycorrhizas, the fungi supplies what two nutrients from the breakdown of organic material in soil?
Nitrogen and Phosphorus
What is one specific insect that has formed a symbiotic relationship with fungi?
Leaf-Cutter Ants
Farm fungal gardens (Cannot eat poisonous tropical vegetation. Instead, chop plants into bits, add mycelium. Fungi grow, digest plant material, produce reproductive structures eaten by ants).
Saccharomyces cerevisiae is used in the production of what three products?
Beer, Wine, and Bread
_______ genetically engineered to produce molecules like human insulin and hepatitis B vaccine.
Yeasts
Saccharomyces cerevisiae (brewer’s or baker’s yeast) is used in the production of what three objects?
Wine, Beer, Bread
What is the biggest example of antimicrobial medicines produced by fungi?
Penicillin
Human illnesses from fungi are caused in three ways:
____________ reaction: allergy or asthma.
Fungus grows on/in body; causes ________ (disease)
________
Hypersensitivity
Mycosis
Intoxication
________ produced by Aspergillus species; found in grains, peanuts; carcinogenic.
Aflatoxins
Amanita species produce toxins that cause fatal _______ damage.
Liver
Rye mold Claviceps purpurea (ergot) produces _________ toxin, purified drug ergotamine.
Hallucinogenic
Algae differ from plants by what two main characteristics?
Organized vascular system and simple reproductive structures.
Algae contain ______ that absorb gradient energy.
Pigments
Are most algae terrestrial or aquatic? Are they microscopic or macroscopic?
Aquatic. Both.
__________ algae include diatoms, some green algae, dinoflagellates, euglenoids, and a few red algae.
Unicellular
Microscopic algae have a relatively large/small absorptive surface.
Large
What is the main example of a microscopic algae that forms colonies?
Volvox
Single celled microscopic algae can be propelled by _______ or free _______, as well as growth in long _______ or ________.
Flagella
Floating
Chains
Filaments
________ incorporate silicon dioxide into cell walls (Crude oil, natural gas)
Diatoms
Some macroscopic algae, like kelp, possess holdfast which is used for ________.
Anchoring
___________ algae includes multicellular brown algae, green, algae, and red algae.
Macroscopic
In macroscopic algae, the stalk (stipe) usually has attached leaflike structures, in which the blades are the main site of _________.
Photosynthesis
In macroscopic algae, what structure helps blades float for maximum sun exposure?
Bladder
Algae are major producers of ____ and major consumers of ____.
O2, CO2
T/F: The main habitats of algae are fresh and salt water, as well as moist soil.
True
T/F: Algae with different pigments live at different depths.
True
Plankton float near the surface; unicellular algae comprise significant portion of ________, which forms the base of the food chain.
Phytoplankton
Microscopic heterotrophs in ______ graze upon phytoplankton; both become food for other organisms.
Zooplankton
Algal reproduction is varied, as some reproduce asexually by ________. Some reproduce sexually through alternation between _____ and _____ generation.
Fragmentation
Haploid
Diploid
Algae do not directly cause cause human disease, but may do so indirectly via ______.
Toxins
Algal blooms of dinoflagellates cause _______.
Red tides
Which animal feeds upon Gonyaulax species that produces neurotoxins that accumulate in their tissue? This does not harm the species, but can cause paralytic poisoning to humans if ingested.
Shellfish
Protozoa means “______-like” and are ________.
Animal
Protists
_______ are unicellular heterotrophic organisms that are not fungi, slime molds, or water molts.
Protozoa
Protozoa are historically grouped primarily by means of _________.
Locomotion
T/F: Protozoa are not a unified group based upon DNA sequences coding for rRNA.
True
__________ are a group of protozoa that are parasites with apical complex at one end that helps penetrate membrane of host cells.
Apicomplexans
Many apicomplexans have complex life cycles that alternate between ______ and ______ forms.
Sexual
Asexual
Plasmodium is an apicomplexan that causes ________, which is one of the most significant infectious diseases in the world.
Malaria
Other human pathogens in the ________ group include Toxoplasma gondii, Cryptosporidium parvum, and Cyclospora cayetanensis.
Apicomplexans
________ and ________ are flagellated protists that lack mitochondria.
Diplomonads and Parabasalids
_________ reside in stagnant water low in O2 or in anaerobic conditions inside host.
Diplomonads
__________ is an example one Diplomonad that causes diarrhea in campers.
Giardia lamblia
Diplomonads typically have how many nuclei and reproduce sexually/asexually?
Two nuclei
Asexually
__________ live within host (in termites they digest cellulose). Others may cause disease (Trichomonas vaginalis).
Parabasalids
T/F: A few parabasalids also reproduce sexually.
True
__________ have a distinct mass of DNA made from interlocking rings in their large single mitochondria.
Kinetoplastids
Kinetoplastids may be a useful target for _________.
Medications
___________ includes some human pathogens, including Trypanosoma brucei (African sleeping sickness), Trypanosoma cruzi (Chaga’s disease), and Leishmania species.
Kinetoplastids
_________ and ________ both have ameboid (flexible) body forms, but are only distantly related to one another.
Loboseans and Heteroloboseans
Loboseans extend and retract ________ and engulf food particles by ________. Entamoeba histolytica causes diarrhea in humans.
Pseudopodia
Phagocytosis
Heterloboseans also form ________ cells. Example is Naegleria fowleri that swims in water, assumes ameboid form upon entering human body, eats host brain.
Flagellated
In protozoa, _______ secrete hard calcium carbonate shell.
Foraminifera
What are the three locomotive structures that protozoa are typically classified upon?
Pseudopodia, Flagella, Cilia
Which group does not contain cellulose or chitinous walls?
Protozoa
T/F: Most protozoa are free living aquatic organisms that are also found in soil or in or on plants and animals.
True
Which group eats a large number of bacteria and algae? Some are parasitic and are deemed essential decomposers in many ecosystems. Zooplankton is a food source in marine environments.
Protozoa
In the protozoa group, Cryptosporidium, Giardia is among leading causes of _______ worldwide.
Diarrhea
Which two subclasses are protists that were once considered types of fungi?
Slime Molds and Water Molds
T/F: Slime molds and water molds may look and act like fungi, but at the cellular and molecular levels are completely unrelated.
True
Fungi and water molds are good examples of _____________ (organisms that develop similar characteristics independently as they adapt to similar environments).
Convergent Evolution
__________ are composed of ameboid cells that live on soil, leaf litter, and decaying vegetation.
Slime molds
Slime molds ingest organic matter by __________.
Phagocytosis
Which subclass is an important link in food chain as they ingest microorganisms and serve as food for larger predators?
Slime Molds
In cellular slime molds, the vegetative form is _______ cells.
Single
When food is low, cellular slime molds aggregate into a mass called a ______; some cells differentiate into spores. Dictyostelium discoideum is model organism.
Slug
In ________ slime molds, cells fuse forming diploid multi-nucleated _______ that ingests organic material. When food is low, forms spore-bearing bodies. Haploid spores fuse to form diploid plasmodium.
Plasmodial
Plasmodium
What is another name for water molds?
Oomycetes
_________ form masses of white threads on decaying material.
Water molds
Do water molds have cellulose or chitin in their cell walls?
Cellulose
__________ secrete digestive enzymes onto substrate. Cytoplasm in filaments continuous with many nuclei. Lack chloroplasts, reproductive cells are flagellated. Important food crop diseases include downy mildew of grapes, potato blight.
Water molds
_________ are animals that are often identified by their microscopic eggs.
Helminths
T/F: Helminths affect industrialized countries just as much as developing countries.
False. Largely controlled in industrialized nations, but infect hundreds of millions in developing world.
Helminths include ______ (nematodes), and ______ (tapeworms: custodies; flukes: trematodes).
Roundworms
Flatworms
Some _______ invade host tissue and rob host of nutrients.
Helminths
Helminths may have complex life cycle with one or more __________ hosts that house an immature stage.
Intermediate
______ are intermediate host for fluke Schistosoma mansoni and _____ are the definitive host.
Snails
Humans
Humans may become accidental or _________ if infected by parasite that normally completes its life cycle in another host (“Swimmer’s itch” caused by larval flukes).
Dead-End Host
Which helminth larvae live in soil and burrow through skin? They multiply in the digestive tract, eliminated with feces. Poor sanitation, bare feet aid in transmission. Approximately 740 million individuals infected.
Hookworm Larvae
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