Classification: Protists and Fungi Flashcards
(17 cards)
Characteristics of protists
A) most diverse kingdom
B) all are eukaryotic
C) mostly unicellular; some are primitively multicellular (i.e., no organs)
D) include organisms that don’t fit in any other kingdom; ex. seaweeds and slime molds
Modes of nutrition: heterotrophic
ex. amoeba and paramecium, parasitic forms, and mutualistic forms (ex. those living in termite’s guts)
Modes of nutrition: autotrophic
(most common types are red, green, and brown algae) ex. kelp, Volvox (a colonial alga); and other more simple or more complex algae
Mode of nutrition: autotrophic, but can become heterotrophic
-If the conditions for photosynthesis are not favorable (or if the chloroplasts are removed from the organism); ex. unicellular euglenas
Amoeba
- Ingestion: pseudopods capture food (phagocytosis)
- Digestion: food enters a newly formed food vacuole and is digested (by enzymes from lysosomes) within
- Photosynthesis: no
- Movement: pseudopods
- Osmoregulation: excess water is pumped out using contractile vacuoles
- Gas exchange/waste removal: across cell membrane by diffusion
Paramecium
Ingestion: cilia sweep food into oral groove (modified phagocytosis)
Digestion: food enters a newly formed food vacuole and is digested (by enzymes from lysosomes) within
Photosynthesis: no
Movement: cilia
Osmoregulation: excess water is pumped out using contractile vacuoles
Gas exchange/waste removal: across cell membrane by diffusion
Euglena
Ingestion: captures food if photosynthesis isn’t possible
Digestion: food enters a newly formed food vacuole and is digested (by enzymes from lysosomes) within
Photosynthesis: light-sensitive red eyespot locates light; chloroplasts
Movement: flagella
Osmoregulation: excess water is pumped out using contractile vacuoles
Gas exchange/waste removal: across cell membrane by diffusion
Reproduction
A) mainly by binary fission (asexual)
B) some (ex. paramecium) carry out a primitive form of reproduction called conjugation, where two individuals exchange genetic material- followed by binary fission
Troublesome forms
A) pathogenic cause the following diseases: amoebic dysentery, malaria, African sleeping sickness, giardiasis; also the cause of the Irish potato famine
B) a type of algae called dinoflagellates cause the infamous red tides that poison water and the fish in it
Characteristics of Fungi
A) heterotrophic
B) eukaryotic; feed by absorbing organic materials; food is digested outside the organism after enzymes are secreted onto it (extracellular digestion); end products of digestion are then slowly absorbed by diffusion
C) cell walls are made of chitin (not cellulose)
D) multicellular forms are composed of filaments care hyphae that penetrate into food and absorb nutrients after releasing enzymes into it
Forms and Examples of Fungi
A) most are multicellular- ex. mushrooms; mold; mildew
B) unicellular form: yeast
Fungi Reproduction
*this is the characteristic used to classify Fungi into Divisions
A) mainly by spore formation (sexual or asexual?)
B) yeast is produced by budding (asexual): similar to binary fission, but unequal sized cells result
Decomposers / organisms of decay
-such fungi are saprobes; they are very important in recycling nutrients in ecosystems (problem, they are not selective and will eat the food we want to eat)
Parasitic
- parasitize animals and plants
1. fungal parasites of humans cause conditions such as: athletes food, jock itch, ringworm, toenail fungus, yeast infections
2. fungal parasites of plants include, the powdery mildew, rusts, and smuts
Symbiosis
mycorrhizae
Lichen
- symbiotic association involving a fungus and a green or blue-green alga
- key pioneer organisms, important in soil formation
Helpful Forms
A) decomposers
B) fermenters (yeast used in brewing)
C) flavor foods such as some cheeses
D) antibiotic production (penicillin)
