microbio Flashcards
give the 3 DNA characteristics of eukaryotes
DNA in nucleus, surrounded by membrane
DNA in several chromosomes
DNA associated with histones and nonhistone proteins
Algae, fungi, protozoa are examples of
eukaryotes
First living cells were
prokaryotes
states that organelles inside eukaryotic cells arose from engulfed prokaryotic cells
Endosymbiotic theory:
Ancestors of mitochondria were
O2-requiring bacteria
Ancestors of chloroplasts were
photosynthetic bacteria
the 5 common External Structures of eukaryotes are
Flagella
Cilia
Glycocalyx
Cell Wall (fungi)
Plasma membrane
A Polysaccharide composed of fibers, capsule or slime layer
Glycocalyx
the cell wall of algae is composed of
cellulose, pectin, mannans, SiO2, CaCO3
the cell wall of most fungi is composed of
chitin (poly NAG)
the cell wall of yeasts is composed of
glucan and mannan
the cell wall of protozoa is composed of
pellicle instead of cell wall
Internal Structures of eukaryotes
Nucleus
Endoplasmic reticulum / ribosomes
Golgi apparatus
Lysosome
Mitochondria
Chloroplasts
Cytoskeleton
most prominent organelle of eucaryotic cell
nucleus
an internal structure by which the nuclear envelope is composed of two parallel membranes separated by a narrow space & is perforated with pores
nucleus
an internal structure that contains chromosomes
nucleus
dark area for rRNA synthesis & ribosome assembly
nucleolus
originates from the outer membrane of the nuclear envelop & extends in a continuous network through cytoplasm
RER
First step in secretory pathway.
proteins are synthesized & shunted into the ER for packaging & transport
closed tubular network without ribosomes, functions in nutrient processing, synthesis & storage of lipids, membrane (lipids) etc.
Smooth endoplasmic reticulum (SER)
functions for transport and modification of compounds
Golgi body
vesicles containing enzymes
Lysosomes
involved in intracellular digestion of food particles & in protection against invading microbes
Lysosomes
folds of mitochondria are called
cristae
consists of an outer membrane & an inner membrane with folds called cristae
Mitochondria
it holds the enzymes & electron carriers of areobic respiration
cristae
TRUE OR FALSE: Chloroplasts are larger than mitochondria
TRUE
primary producers of organic nutrients for other organisms
Chloroplasts
flexible framework of proteins, microfilaments & microtubules form network throughout cytoplasm
cytoskeleton
involved in movement of cytoplasm, ameboid movement, transport, & structural support
cytoskeleton
TRUE OR FALSE: Eukaryotic ribosomes are larger than procaryotic ribosomes
TRUE
ribosomes are composed of
rRNA and proteins
Eukaryotic “Microbes” includes
Fungi
Protists
Algae
Protozoan parasites
Helminths (multicellular animals)
Largest living beings
Fungi
____ are long filaments
hyphae
TRUE OR FALSE: Fungi Are Dimorphic
TRUE
Fungi Are Dimorphic because:
it has yeastlike and moldlike growth
fungal reproduction are primarily through ______ formed on special reproductive hyphae
spores
spores are formed through budding or in conidia or sporangiospores
asexual reproduction
spores are formed following fusion of male & female strains & formation of sexual structure
sexual reproduction
____ are free spores not enclosed by a spore-bearing sac.
Conidia (conidiospores)
are formed by successive cleavages within a saclike head called a sporangium, which is attached to a stalk, the sporangiophore.
Sporangiospores
Fungi are heterotrophs (chemoheterotrophs), that feed by ________
absorptive nutrition:
growth temperature of fungi
20o-40oC
give the Importance of Fungi:
- decomposers
- mutualistic symbionts with plants: mycorrhizae
- parasites/pathogens: cause some diseases in plants and people
- economically useful to people (food, medicine, hallucinogens, alcohol/bread production)
enumerate the 5 groups of fungi
Chytridiomycetes
Zygomycetes
Glomeromycetes
Ascomycetes
Basidiomycetes
Aquatic with flagellated cells group of fungi
Chytridiomycetes
molds responsible for rotting of foods such as bread, peaches, strawberries, and sweet potatoes.
Zygomycetes
black bread mold is called
Rhizopus
Rhizopus (black bread mold) produce ____
sexually
“Vesicular-arbuscular” mycorrhizae
Glomeromycetes
symbiotic (mutualistic) association between a fungus and the roots of a plant
mycorrhiza
essential for the growth of many plants: help plant to absorb water & mineral nutrients (esp. Phosphorous)
mycorrhizae
All united by having an ascus
Ascomycetes (Ascomycota)
sac containing walled spores (ascospores)
Ascus
Two major groups of Ascomycetes are:
Hemiascomycetes
Euascomycetes
a group of ascomycetes with
no fruiting structure
Hemiascomycetes
a group of ascomycetes with fruiting structure
Euascomycetes
Infects rye: “Ergotism” or “St. Anthony’s Fire”,
Ergot [Claviceps purpurea]
Caused hallucinations, miscarriages, madness, convulsions, death in europe on 600 BC
Ergot [Claviceps purpurea]
Medincinal value of ergot:: used to treat migraine headaches.
Ergotamine
Medincinal value of ergot:used to induce labor [causes uterine contractions, prevents hemmorage.]
Ergonovine
1943, _______ Swiss chemical plant, studied ergot alkaloids, all of which have lysergic acid as a base; added diethylamide to make lysergic acid diethylamide (LSD).
Albert Hoffman
penicillium belongs to which group of fungi?
Euascomycetes
yeast belongs to which group of fungi?
ascomycetes
used in production of soy sauce and
other flavorings
Aspergillus, Euascomycetes
some species of aspergillus grow on nuts, produce ________
carcinogenic aflatoxins
used in production of sake (Japanese alchoholic beverage; breaks down starches to sugars)
Aspergillus, Euascomycetes
Basidiomycetes (Basidiomycota) include
Mushrooms
Shelf fungi
Puffballs
Jelly fungi
- site of meiosis in basidiomycetes - spores (basidiospores) extruded to outside
Basidium
examples of Basidiocarps: with mostly dikaryotic hyphae
Puffballs
mushrooms
shelf fungi
Importance of Basidiomycetes
Important decomposers
Edible basidiomycetes
Agaricus bisporus, Shitake
Poisonous basidiomycetes
Amanita spp. Destroying Angel
Can grow in extreme habitats (e.g., endolithic lichens in Antarctica)
But, very sensitive to air pollution
lichens
Fungi have keratinase – degrade keratin on skin, nails and hair
Cutaneous mycoses
Special problems in immunocompromised hosts
Systemic mycoses
photosynthetic protists
algae
examples of algae
kelps, seaweeds, euglenids, green algae, diatoms, dinoflagellates, brown algae, & red seaweeds
algae are classified according to:
classified according to types of pigments & cell wall
Dinoflagellate algae that causes red tide
Pfiesteria piscicida
most are unicellular, colonies are rare
most have locomotor structures – flagella, cilia, or pseudopods
Protozoa
lack a cell wall & chloroplasts
can exist in trophozoite- motile feeding stage or cyst – a dormant resistant stage
protozoa
are all protozoa heterotrophic?
yes
Groups based on locomotion & reproduction (protozoa)
Mastigophora – flagellates
Sarcodina – amebas
Ciliophora – ciliates
Apicomplexa – all parasites motility not well developed; produce unique reproductive structures
causes malaria
fever, chills, anemia
transmitted by mosquito bite
Plasmodium falciparum
symptoms of malaria include
fever, chills, anemia
infects small intestines
has no mitochondria
Giardia lamblia: giardiasis
infects nervous system and heart
carried by kissing bugs
Chaga’s Disease
pathogenic bacteria in Chaga’s Disease
Trypanosoma cruzi
characteristics of helminths
Highly specialized to live inside hosts
May lack digestive system
Reduced nervous system
Reduced locomotion or lacking
Reproductive system is complex
example of Pathogenic Helminths
Flukes
Tapeworms
Hook worms
Pin Worms
5 evidences of endosymbiotic theory
size
two membranes
circular DNA
mitochondria
chloroplasts
rRNA is produced from which part of the cell
nucleolus
lysosomes are created by
ER
expansion of fungi is due to
hyphae
main decomposers of the planet
saprobes
black knot
Dibotryon morbosum
Primary medical threat of algae
neurotoxins
caused by exposure to schistosome-infested
water
Cercarial dermatitis
Asian Liver fluke
Trematodes
tapeworms
Cestodes