Lectures 5&6 Flashcards
Eukaryotes that do not have distinctive features of animals, plants, or fungi
Paraphyletic group
Fossils of protists are found in rocks that are ____ BYA. The first protists appeared after ___ became abundant in the atmosphere and oceans
1.8-1.5
oxygen
Protists that lived millions of years ago settled to the sea floor. Pressure and heat transformed them into ____ and ___
Petroleum
Natural Gas
Eukaryotes that do not have the distinctive features of animals, plants, or fungi
Protista
Characteristics of protista cell surface. Some with ____ only and others with ___ made of different material
plasma membrane
cell wall
Protista mechanisms of movement.
Motile or non-motile
Three types of motile appendages of protists
pseudopodia
flagella
cilia
Transient projections of the cytoplasm
Pseudopodia
Three types of protist body structure
Unicellular
Colonial
Multicellular
Most protists live in water, moist soil, or ____
moist interiors of other organisms
What are the 5 Types of asexual reproduction of protists
Spores Binary fission Budding Schizogony Fragmentation
A haploid structure, usually unicellular, that can be dormant and eventually give origin to an adult organisms without fusion to another cell
Spore
What are the 3 types of sexual reproduction of protists
Haplontic (zygotic meiosis)
Diplontic (gametic meiosis)
Haplodiplontic (sporic meiosis, alternation of generations)
Animals and some protists have this life cycle. The only haploid cell in the cycle are the gametes. Only the diploid cell undergo mitosis. The gametes do not divide
Diplontic life cycle
Occurs in most fungi ad some protists. The only diploid cell in the cycle is the zygote. The dominant generation is the haploid generation. Only the haploid cells undergo mitosis.
Haplontic life cycle
Life cycle of most lats and some protists. Both diploid and haploid cells undergo mitosis.
Haplodiplontic life cycle
Protists are alike in that all ____
have a nucleus
Eukaryotes are divided into 6 monophyletic supergroups. Each supergroup includes ____. Each supergroup is a ____
protists
clade
A group of species that includes the ancestral species and all its descendants.
Clade
The classification of organisms is based on analysis of
DNA sequences
Unicellular with feeding grooves on the side of their bodies
Excavata
Lack functional mitochondria. Have two nuclei. Example is Giardia which causes diarrhea (hiker’s diarrhea)
Diplomonads
Lack functional mitochondria. Have undulating membranes. Example is Trichomonas vaginalis which causes inflammation of the vagina.
Parabasalids
Some Excavata live in the gut of termites and digest wood. Symbiotic relationship among three organisms:
The termite, the protist, and the bacteria that digest cellulose.
Have a rod inside their flagella
Euglenozoa
Unicellular with two flagella. Some photosynthetic with chlorophylls a and b and carotenoids. The chloroplasts derived from endosymbiosis of a green alga (secondary endosymbiosis)
Euglenoids
Some euglenoids may ingest food particles by phagocytosis and some are ____
heterotrophs
Euglenoids have protein bands beneath their plasma membrane called a
pellicle
Euglenoids are considered to be part of ____
plankton
Heterotrophic, only one mitochondrion, unicellular or colonial with at least one flagellum. Can be free living parasites. One example is Trypanosoma which causes sleeping sickness and Chagas.
Kinetoplastids
Which characteristic is used to classify an organism within the Excavata?
Its DNA sequences are more similar to organisms within the Excavata than to those of organisms in other subgroups
Chromalveolata is a supergroup that includes ___ and ____
Alveolata and Dinoflagellates
Have alveoli vesicles beneath the plasma membrane which may increase their buoyancy
Alveolata
Unicellular with two flagella. Many are photosynthetic with chlorophylls a and c and carotenoids. Have cellulose in their cell walls. Part of marine and fresh-water plankton
Dinoflagellates
Certain dinoflagellates secrete ___
neurotoxins that can kill fish and birds (ex: red tides)
Parasites of animals. Have a unique arrangement of organelles at one end of the cell (apical complex) that allows them to invade host cells
Apicomplexans
An example of an Apicomplexan is ____ which causes malaria and is transmitted by mosquitoes
Plasmodium
With malaria the parasite reaches the liver where it
reproduces and invades the RBC’s
In the red blood cells the Plasmodium parasite multiplies and periodically
rupture RBC’s which is associated with fever and chills
Unicellular, large number of cilia, two nuclei.
Ciliates
The micronuclei of ciliates is involved in ___. The macronuclei contains ____
sexual reproduction
many copies of the gene
Unicellular, chlorophylls a,c, and carotenoids, silica cell walls, Chrysolaminarin storage, marine and freshwater plankton
Chromalveolata: Stramenopila: Diatoms
Multicellular, chlorophylls a, c, and carotenoids, marine environments
Chromalveolata: Stramenopila: Phaecophyta/Brown Algae
Water molds, white rusts, downy mildew. Filamentous bodies that consist of hyphae. Cell walls with cellulose. Zoospores with two flagella. Heterotrophs: saprobes or parasites.
Chromalveolata: Stramenopila: Oomycota
The supergroup
The chloroplasts originate from primary endosymbiosis of photosynthetic bacterium.
Include rhodophyta or red algae
Archaeplastids
Mainly multicellular Chl a, phycoerithrin, and carotenoids Cell walls with sulfated polysaccharides Used to make agar and carrageenan Live in marine environments
Archaeplastids:Red algae
- Unicellular, colonial, or multicellular
- Chl a, b, and carotenoids
- Cellulosic cell walls
- Starch is the storage polysaccharide
- Mainly aquatic (marine or fresh water) some in moist terrestrial environment
Archaeplastida: Chlorophyta
Green algae and diatoms are likely to be increasingly important for
food and fuel production
Archaeplastida: Chlorophyta: Chlorella is commonly used as a
nutritional supplement and animal feed
Archaeplastida: Charophyta: Green algae is commonly used as a ____
biofuel
- Unicellular, colonial, or multicellular
- Chl a,b, and carotenoids
- Cellulosic cell walls
- Starch
- Freshwater habitats
- The group of algae that is most closely related to land plants
Archaeplastida: Charopytes
The intercellular connections of Charophytes (plasmodesmata) are similar to those of _____
plants
All land plants evolved from a species of ____
Charophytes
In a marine env you find a photosynthetic organisms that is multicellular and has chloroplasts with 4 membranes. This organism is most likely a
Brown algae
The one supergroup where the origin of the chloroplast is the result of primary endosymbiosis (chloroplast only has two membranes)
Archaeplastida
In secondary endosymbiosis the chloroplast of organism will have ____ membranes
4
-Threadlike pseudopodia used for movement and to trap food particles
Rhizaria
- Exoskeleton or wall is made of silica
- Pseudopodia extrude through spike projections of the exoskeleton
- Marine env part of the zooplankton
Rhizaria: Radiolarians
- Cell wall contains organic and inorganic materials
- The pseudopodia emerge through the perforation of the exoskeleton
- Marine env part of the sooplankton
Rhizaria: Foraminifera
- Difficult to define based on structural features
- Some have silica-based shells others without them
- Some with flagella
- Abundant in the soil
- Heterotrophic feeding on bacteria, fungi, and other protists
- One group enslaved a green algae (secondary endosymbiosis)
Rhizaria: Cercozoa
Lobe shaped pseudopodia, lack of cell walls
Amoebozoans
___ and ___ are Unikonts the common ancestor had a single emergent flagellum. The characteristic of having flagellum has bee lost in many descendants is restricted only to a few cells in the life cycle
Amoebozoans and Opisthokonts
- Many species
- Pseudopods
- Asexual reproduction only
- Marine, freshwater, or terrestrial
- free living or parasitic
Amoebozoans: Amoebas
- life cycle contains unicellular and aggregate forms
- unicellular amoeboid forms ingest bacteria
- Lack of food can trigger aggregation as an aggregate they can move like a slug
Amoebozoan: Cellular slime molds
- the nucleus of the zygote divide several times without cytoplasmic division
- This results in the formation of multinucleate structure known as a plasmodium which can move and ingest bacteria
Amoebozoa: Plasmodial slime mold
- single celled or form colonies during part of their life
- have a single flagellum surrounded by a collar (choano)
- flagellum is used for swimming and also beats bacteria through the collar for feeding
- are the closest relatives to animals
- Evidence: molecular data
- Sponges (animals) have some cells that are very similar
Opisthokonta: Choanoflagellida
Among the organisms listed our closest relatives are
- green algae
- oomycota
- choanoflagellates
- diatoms
- apicomplexans
Choanoflagellates
Algae are primary producers in Part of \_\_\_ Symbiotic relationship with \_\_\_ Heterotrophic protists are part of the \_\_\_\_\_\_ Some protists cause \_\_\_\_ Some protists are \_\_\_\_
aquatic ecosystems phytoplankton animals zooplankton disease decomposers
