Eukaryotes Flashcards
Compare Eukaryotes and Prokaryotes on 5 points
E
Paired chromosomes, membrane bounded
Histones
Have membrane bounded Organelles
Polysaccharide cell walls
Mitotic spindle
P
One circular chromosome, not membrane bounded
No histones
No membrane bounded organelles
Peptidoglycan cell walls (bacteria)
Divide by binary fission
Types of eukaryotic microbes
Fungi, algae, protozoa, helminths (multicllular animals/ worms NOT actually microbes)
Two forms of fungi
Unicellular - yeasts (Bakers, OR cause inflammation of V)
Multicellular - molds (Penicillium)
saprophytic
normally live on decaying organisms
How is fungi beneficial?
Decompose dead plants
Symbiosis with palnts
Some are food
Produce medicines
What structure do fungi have?
Vegetative
Septate hyphae
A type of fungal structure divided into different cells by septums
Coencocytic hypahe
A type of fungi without any divisions by septums
Pseudohyphae
Result of icomplete budding, no cytoplasmic connection
How does fungi reproduce
Asexually by spore release
Sexually by mycelium connections and then spore release
What is yeast
Unicellular fungi
What does the term Dimorphic fungi
imply?
Two forms of fungi
Yeast like (37C)
Mold like (25C)
Candida albicans
Yeast infection
superficial known as Candidiasis
Systemic: Candidemia
Most eukaryotic cells reproduce via
Mitotic spindle
What form of reproduction does yeast use?
Budding
Why are systemic yeast infections so dangerous?
Bc any drug used to attack these cells will ALSO attack your cells as well bc both are eukaryotic
3 main problems associated with pathogenic fungi
Mycoses
Mytoxicoses (Mycotoxins)
Hypersensitive allergic reactions
Examples of mycoses
Ringworms
Cadida albicans
Crypococcus neoformans (Meningitis)
Mytoxicoses (Mycotoxins)
Fungal secondary metabolites, toxic to humans/animals EVEN AT LOW DOSES
(aflatoxins) - attack peanut plants
Most acidogenic naturally occurring compounds
Fumonisins: Produced by fungus that love corn - causes neurological affects in developing fetus
Farmers lungs
Allergic reaction resulting from breathing in spores that produced by fungus in the hay
How does a Fungi that produce keratinase affect people?
Degrades keratin in skin nails and hair
3 common types of mycoses (fungal infection of body tissue)
Cutaneous
-Subcutaneous
Systemic
What kind of infection is athletes foot?
Cutaneous mycoses
Epidermophyton floccosum
Tinea pedis
What fungus is the major cause of ringworm
Microscoporum canis
- affecting the skin, hair, and nails
Do protozoas require hosts?
may require several hosts to complete life cycle
Types of protozoa hosts
Definitive host (Host in which parasite matures or reaches reproductive stage and is able to reproduce)
Intermediate host (Harbors developmental stages (larveae)
How to protozoans reproduce?
Fission
Budding: Small bud grows on parent (containing dna material, becomes it’s own cell)
Schizogony: Organism undergoes fission of the nucleus without splitting cells
Schizogony
Form of reproduction in protozoans where the Organism undergoes fission of the nucleus without splitting cells
Giardia lambia
Protozoan that can form cysts
Infects intestines: giardiases (Beaver fever)
What is a cyst
(Like endomspore but for eukaryotes): under unfavourable conditions, survival stage
Trophozooite
Vegetative stage of protozoa, where someone should be treated for a parasitical infection
Trichomonas vaginalis
Anaerobic flagellated protozoan parasite
Most common pathogenic protozoan in industrialized countries
Causes STI - trichomonisasis
Women usually symptomatic and men can be symptomatic
Fishy smelling vaginal discharge
What does Trichomonas vaginalis cause
STI trichomonisasis
Toxoplasma gondii
protozoa infection spread by felines
Who are the hosts of Toxoplasma gondii?
Definitive hosts are the felines
Intermediaate hosts are people or warm blooded animals
How does Toxoplasma gondii spread?
Cats eat contaminated meat (cysts)
Gametes fuse to form oocysts in gut epithelium of cats
Oocytes shed in cat feces
Sporulated oocysts taken up via food or water
Warm-blooded animals (intermediate hosts)
Stages of oocyst development take place in heart, brain, eyes etc.
Why shouldnt pregnant women do cat liter
Could be exposed to Toxoplasma gondii which Can cross the placenta into the devloping fetus to cause miscarriage or fetal neurological damage
Tachyzoites
(fast reproducing forms of the intermediate stage)
Sporozoites from oocytes differentiate into tachyzoites (rapid) in epithelial cells of small intestines of warm blooded hosts.
Bradyzoites
(organism starts to slow down, less reproduction, may become cysts)
In intermediate host, cysts for in brain, heart, eyes, and fetus
Cats eat cyst-containing meat to start the cycle cysts.
What are the hosts of malaria
Definitive host
Anopheles mosquito (female)
Bite for blood meal that is essential for the devlopment of their eggs
Sporozoids contained into sporozoidal glands
When anticoagulation chemicals released into body, sporozoids are released as well
Intermediate host: Humans
How does malaria affect the intermediate hosts
Red blood cells are lysed by merozoites
Untreated malaria, organisms end up blocking capillaries to brain and heart
Explain the plasmodium cycle of reproduction
Sporozoites migrate to liver of human
Undergo schizogony and merozoites are produced
Merozoites invade RBCs and reproduce
RBC ruptures releasing meroizoites to continue process and gametes to be passed on
Characteristics of helminths
Reduced or lack of digestive system
Reduced nervous system (no need to sense)
Reduced locomotion
Complex reproduction
What is implied by the complex reproduction of helminths
Dioecious (serpeate male and female animals) or monoecious (both female and male reproductive organs - hermaphrodites)
Egg - larva(e) - adult
Two forms of helminths
Flat worms (Platyhelminthes): Tapeworms, flukes
Nematodes: Roundworms, pinworms
How do helminths enter n=body
Through ingestion (eggs often found in animal muscle, therefore, will be ingested if undercooked)
Parts of tapeworm
Neck, very small are - most of the growth takes place
Sucker: Nutrient sucked in
Scolex (The whole head)
Hooks: Attatch to intensitinal wall
Proglottid: parts of worms that mature, farther from the neck, more mature eggs inside. Will eventually break off and disintegrate to release eggs
Contain testies, geneital pore which ocnnects sperm to ovaries
Proglottid
parts of worms that mature, farther from the neck, more mature eggs inside. Will eventually break off and disintegrate to release eggs
Trichinosis
Roundworm infection Caused by eating raw or undercooked pork or wild game infected with larvae of roundworm
Ascaris lumbricoides
Infection by nematode worms
Life cycle of Ascaris lumbricoides
Human ingests egg; egg hatches in intestine; larva crosses intestinal wall and travels to lung; larva is swallowed and matures in intestine; adult females lay eggs; eggs exit host in stool.
A unicellular, photosynthetic nucleated cell would belong to which domain?
Eukaryote
What are the reproductive spores of fungi called?
Hyphae
What is algaes cell wall composed of
Cellulose
Protozoa unicellular or multi
Unicellular
Are humans the deffinitive or intermediate hosts for helminths?
Either
Where are Helminths found in the body
Can be found in a vareity of different body systems
Do any eukaryotes lack a mitochondria
Giardia and Trichomonas
most effective control for malaria
eliminate Anopheles mosquitoes
You see acid-fast oocysts in a fecal sample from a patient who has diarrhea. What is the MOST likely cause?
Cryptosporidium
How are helminth eggs released
Section of worm called proglottids breaks off and dissolves
Mebendazole acts against Ascaris lumbricoides by __________.
inhibiting the formation of microtubules, which prevents the worms from absorbing nutrients
heterotrophic
Eats other animals or palnts instead of making it;s own food
Strategies for treating a yeast infection
a topical over-the-counter ointment, such as clotrimazole or miconazole
a single oral dose of fluconazole
C albicans causes
Vaginal yeast infection
Oral thrush
fulminating disease
fulminating disease
results when the yeast enters the bloodstream and travels throughout the entire body, resulting in a systemic infection. Individuals suffering from AIDS are susceptible to this type of infection.
How do blastoconidia and chlamydoconidia produced by yeast differ from bacterial endospores?
Blastoconidia and chlamydoconidia are spore structures produced by budding in yeasts, whereas bacterial endospores are produced by bacteria under extreme conditions.
How do pseudohyphae in yeasts differ from vegetative hyphae in filamentous fungi?
Yeasts use pseudohyphae to invade host tissue, whereas filamentous fungi use their vegetative hyphae for obtaining nutrients.
A definitive host harbors which stage of a parasitic cycle?
adult
Taenia saginata and Taenia solium;
tapeworms
Best way to prevent human infection by tapeworm
Cooking raw meat to kill eggs
Infecting more than 2 billion people worldwide, ________ are the most common causes of chronic infectious diseases.
intestinal roundworms
