Chlorophyta And Rhodophyta Flashcards
Zygotes meiosis
Organisms are haploid
Zygote is the only diploid structure (short lived so not alternation of generations)
No alteration of generations
Dominant gametophye
Unicellular gametophyte
Fungi, some algae
Gametic meiosis
Zygotes continue to divide mitotically-> multicellular adult sporophyte
Delayed meiosis (no alteration of generations: only one multicellular generation)
Gametes are the only haploid cells
Most animals, green and brown algae
No gametophyte
Dominant multicellular sporophyte
Sporic meiosis (isomorphic)
Alteration of generations (two multicellular generations)
Same size in multicellular stages
Isomorphic alternation of generations (many algae)
One generation may be more dominant than other
Sporic meiosis (heterotrophic)
Alternation of generations
Many plants
One generation is clearly the dominant and larger generations and the other is of lesser importance or size
Two distinct events occur during fertilization
Plasmotomy: fusion of gamete Protoplast=single cell with two haploid nuclei
Karyogamy=fusion of two nuclei
In fungi, may persist with two haploid nuclei, without kayogamy
This is known as …..
Dikayotic
Phylum Chlorophyta is predominantly a _____ phylum (habitat)
Freshwater
Chlorophyta means
Green algae
Phylum Chlorophyta includes five morphological types with orders
- Motile, unicellular and colonial (Volvocales)
- Non-motile, unicellular and colonial (Chlorellales)
- Filamentous (Oedongoniales)
4.Membranous (Ulvales)
5.Siphonous (Caulerpales)
Class Chlorophyceae
Order Vilvocales
Characteristics
-motility
-lifestyle
-organelles
-only order with motile, vegetative cells
-either colonial or unicellular
-individual cells usually have 2 flagella
-flagella are apical and equal
-definite cell walls, eyespots, one or more pyrenoid bodies, and cup shaped chloroplasts
Class Chlorophyceae
Order Vilvocales
Reproduction
Unicellular membranes reproduce asexually by zoospores or binary fission
Colonial species are coenoboic and resource by daughter colony formation
Almost all species demonstrate isogamous sexual reproduction with the dominant generation being haploid
Volvocales and Ubiquitous are most often found where
Shallow, freshwater areas such as puddles, ditches and ponds
Particularly those with high organic content
Class Chlorophyceae
Order Volvocales
vacuoles
Do not have large central vacuoles, but have one or more osmoregulation contradict vacuoles
Chlamydomonas sp.
Taxonomy
Class Chlorophyceae
Order Volvocales
How do Chlamydomonas reproduce
Asexually by either cell division within the parent cell or the formation of zoospores
Sexual reproduction in Chlamydomonas is ________ (entire cell becomes a gamete)
Holocarpic
Two individuals of different strains of the same species fuse to form a non flagellate zygote (isogamous)
The zygote divided meiotically to form four haploid flagellated meiospores
The meiospres enlarge to the size of the vegetative adults
Pyrenoid
Center of starch formation inside chloroplast
Gonium sp
Taxonomy
Class Chlorophyceae
Order Volvocales
Gonium sp.
Lifestyle and reproduction
Individuals form flattened colonies of 4-32 cells
Individuals in their genus are coenboic: each colony has the same number of cells. Coordinated movement. Dead cells within a colony are not replaced. Reproduce by forming daughter colonies
Volvox sp
Taxonomy
Class Chlorophyceae
Order Volvocales
Volvox lifestyle and asexual reproduction
Form daughter colonies to reproduce asexually. Several cells in the parent colony differentiate into reproductive cells called gonidia. Gonidia divide and form miniatures of the parent colony within the hollow parental sphere. Daughter colonies are released through the rupture of the parent colony.
Volvox sexual reproduction
Gonidia either become eggs or Sperm packets aka reproduction is oogamous
The species may be monoecious or dioecious. The sperm packets are released and swim as units to receptive colonies. Following fertilization, the zygote develops a spiny outer wall. Finally, the zygote divides meiotically to produce a single motile zoospore. This cell swims for a short period then divided to form a small colony
How do volvox move
Coorinated movement of flagella in colonies
How many cells can be in a volvox colony
Around 50,000
Gonidia
Large, non motile cells that divide to produce miniature colonies (same number of cells as parent)
How many eggs and sperm packets per gonidium
1 egg
1 sperm packet = 64-128 gametes (half moons)
Spermatids packets swim as ____
Units
Class Chlorophyceae
Order Chlorellaes
Lifestyle
Reproduction
Organelles
Contains unicellular and colonial green algae. May be coenobic or irregular. Cells may be Uni or multi nucleate. Chloroplasts are well defined and appear as discs, cups or bands. Pyrenoid bodies are common.
Contain no motile vegetative cells
Asexual reproduction is by sporulation, fragmentation or daughter colony formation, but never by binary fission
Sexual reproduction is isogamous, an isogamous or oogamous
Anisogamy
Gametes flagellated, large and small
Oogamy
Large egg (sessile), small sperm (motile)
Chlorella sp
Taxonomy
Class Chlorophyceae
Order Chlorellaes
Chlorella sp
Habitat
Reproduction
Chloroplast specialization
Freshwater and marine
Asexually by forming 4,8 or 16 auto spores (non motile spore from cell wall of parent) within the original parent cell wall.
1 chloroplast per cell
Never sexual reproduction
Scenedesmus sp
Taxonomy
Class Chlorophyceae
Order Chlorellaes
Scenedesmus sp.
-lifestyle
-reproduction
-flagella
Colonial (groups of 4 cells)
Reproduce by daughter colony formation.
Miniatures of the parent colonies are formed within each of the parent colony cells. The cell walls rupture releasing daughter colonies.
No flagella, have spines
Pediastrum sp.
taxonomy
Class Chlorophyceae
Order Chlorellaes
Pediastrum sp.
-lifestyle
-habitat
-appearance
Coenobic species, common to freshwater, each consisting of individuals which exist as flats plates of cells. The outer cells of the plate and often some of the inner cells have one or two horn-like spines.
Pediastrum reproduction
Asexual: daughter colonies without parent cells in the colony. Cells first form zoospores. Zoospores align in approximate shape of the parent colony, lose their flagella and assume the shape of miniature parent cells. Then released from parent cells.
Sexual: Isogamous gametes
Class Chlorophyceae
Order Oedogoniales
-structure
-reproduction
-primarily simple filaments
-most reproductively advanced groups in phylum Chlorophyta
-asexual reproduction is through multiflagellate zoospores
-sexual reproduction is oogamous, between individuals of monoecious or dioecious species
Class Chlorophyceae
Order Oedogoniales
Cells
Vegetative cells are uni nuclear with a diffuse, reticulate chloroplast around a central vacuole.
Oedogonium sp
Taxonomy
Class Chlorophyceae
Order Oedogoniales
Oedogonium sp.
-appearance
-Make be female
Simple filaments which lack a definite chloroplast in each cell.
Unbranched, uniseriate filament, which is usually at Taft he’d by a modified holdfast cell but may become free floating in dense mats
Terminal cell of the filament is often marked with several rings
Caps
Ring like scars from cell wall formation
Oedogonium sp
Macrandrous
Nannandrous
Similar size of the male and female filaments
Large female with attached dwarf male filaments
Oedogonium sp
Size and male vs female
Macrandrous and dioecious (male and female gametes produced by separate individuals) vs monoecious (gametes produced on same individuals
Class Ulvophyceae
Habitat
Appearance
Reproduction
-predominantly marine
-filamentous and multinucleate or flat, single or double sheets of uninucleate cells.
-asexual reproduction by zoospores or Aplanospores
-sexual reproduction involves formation of ansiogametes but the zygotes frequently divide meiotically to procure a diploid individual that is similar to the haploid form in appearance.
Ulvophytes are the only green algae to have _______
An alternation of generations
Ulva sp.
taxonomy
Class Ulvophyceae
Order Ulvales
Order Ulvales members have ______ thalli
Parenchymatous
Ulva sp.
-habitat
-common name
Marine
Sea lettuce (large flat thalli
Class Ulvophyceae
Order Ulotrichales
Habitat
Appearance
Benthic
Filamentous green algae
Simple, unbranched filaments with little to no cell differentiation.
Only the terminal cell will differentiate into a holdfast for attachment
Uninucleate and contain one or several discoid chloroplasts
All cells in order Ulotrichales are capable of ________
Dividing to produce zoospores or isogametes
These motile cells are bi or quadri flagellate
Ulothrix sp.
taxonomy
Class Ulvophyceae
Order Ulotrichales
Ulothrix sp.
-habitat
-appearance
-chloroplast
Benthic in marine or freshwater
Single chain of 20-30 cells
Differentiated holdfast to attach to different forms of substrate.
Each cell has a horseshoe shaped chloroplast encircling a large central vacuole
Class Ulvophyceae
Order Caulerpales
Appearance
Habitat
Siphonous=coenocytic (multi-nucelate) algae are Maine organisms
Single or multi-axial systems which have no cross wall except at reproductive structures
Species of order Caulerpales
Bryopsis
Codium
Class Ulvophyceae
Order Chladophorales
Clasophora sp.
-habitat
-appearance
Manitoba water or marine
Forms large blooms of dense algal mats
Filaments are composed of large, multi-nucelare, separate cells with numerous, small chloroplasts
Class Charophyceae confusion of taxonomy
-vegetative structures resemble algae but gametangia are surrounded by protective covers of sterile cells. This is characteristic separates algae from plants.
-link to bryophtes (mosses) and vascular plants (ferns and seed plants) include presence of asymmetrical flagellated cells, similarities in mitosis and cytokinesis, presence of flavonoids and the precursors of the cuticle.
Charophyceae appearance and habitat
Unicellular, filamentous and parenchymatous genera.
Freshwater, anchored by rhizoids in sandy or muddy substrates
Class Charophyceae
Order Zygonematales
Spirogyra and Demids difference and similarity
Spirogyra- filamentous, spiral chloroplasts
Desmids-unicellular but constructed from two hemi-cells.
Placed in common order because they exhibit conjugation, a form of sexual reproduction
Conjugation
Form of sexual reproduction
-cells align and form conjugation tubes between male and female gametes
-triggered by environmental stress (changes in pH, temperature or desiccation)
Class Charophyceae
Order Charales (stonewarts and brittle warts)
Chara sp.
-habitat
-appearance
-Manitoba
-can grow up to 30cm tall and be mistaken for a vascular plant
Chara sp.
-Main stem
Main stem is more than 1 cell wide. One long central cell that extends throughout the whole internodal region. This cell is surrounded by several pericentral cells that do not extend the entire internodal region. All of the growth originated from an apical cel at the end of the stem.
Reproduction of Chara sp.
Primarily sexual (oogamous). Limited amount of fragmentation, particularly at the rhizoidal region. Sexual reproduction is oogamous and the plants may be monoecious or dioecious. Gametangia develop in the axis at the nodes.
Chara sp. precipitate what around leaves and stems?
CaCO3
Antheridium and Oogonium of Chara sp
Shield cells and antheridial filaments. Each antheridial filament produces a single sperm cell by mitosis.
Oogonium surrounded by strike cells but inside there is only one Single egg cell
Fertilization of Chara sp. is _____
Germination occurs by
Internal and the zygote eventually germinated by producing a small filament out through a split in the outer cells
Rhodophyta means
Red algae
Rhodophyta belong to a group of algae that form the vast majority of the _____
Sea weeds
Where do Rhodophyta live
Enormous geographical range, from tropical to arctic waters
Few live in freshwater
Rhodophyta and reef building
Coralline algae: deposit CaCO3 in cell walls
Fossil record to Precambrian (1.5bya)
Reproduction of red algae
-vegetative reproduction is rare
-alteration of 3 generations and the formation of different types of spores
Characteristic feature of red algae
Passive, no /flagellated sperm cells (spermatia)
Gametophyte generation of red algae and reproduction
Usually large monoecious plants. These produce carpogonia (female) and antheridia (male) gametangia on the same or on different branches. Carpogoniuk produce an egg and has an elongate terminal projection called a Trichogyne. The antheridium releases the spermatia into the water. These eventually float into contact with the trichogyne. A sleek nucleus penetrates the cell wall upon contact with the trichogyne and migrates to the egg nucleus. Fertilization results in a diploid zygote. The zygote divides and forms a diploid carposporophyte generation. The carposporophyte may be enclosed in a haploid outer covering called a pericarp or may be naked.
The carposporophyte is a ________ generation, which remains attarched to the gametophyte
Diploid
Through mitosis, the carposporophyte produces diploid _______ in ______
Carposporophyte
Carposporangia
In Polysiphonia sp. the carposporophyte are released through a _____
Small hole in the end of the pericarp
The production of carpospores increases the __________
Numbers of reproductive units in the life cycle
Carpospores drift away and settle where?
Bottom where they germinate into the second diploid generation (tetrasporphyte generation)
Tetrasporophyte
Resembles the free living gametophyte and produced tetrapsporangia
Clusters of four haploid tetraspores are produced by meiosis in each tetrasporangium. After their release, tetraspores germinate to form new gametophytes.
Phylum Phodophyta
Order Bangiales
Porphyra sp.
Common name
Appearance
Nori
-membranous form, made up of a single layer of cells embedded in a thick layer of mucilaginous material.
-thalli appear as bright red “leaves” attached at the base of rocks.
Phylum Phodophyta
Order Bangiales
Porphyra sp.
Reproduction
In sexual reproduction, the marginal cells become carpogonia by extending trichogynes
The inner section metamorphose into spermatangis
Phylum Rhodophyta
Order Nemalionales
Batrachospermum sp.
-habitat
-dominant when?
-appearance
Freshwater red algae, colder spring-fed lakes and cooler running streams.
Dominant in haploid gametophyte
Filamentous
Phylum Rhodophyta
Order Cermiales
Polysiphonia sp.
-appearance
-generations
-most advanced order of Rhodophyta
-appears as filiform, branched and bushy organisms, although some are membranous
-3 distinct generations
-distinct male and female gametophytes (dioecious)
-carposporophyte generation is surrounded by a haploid pericarp
Most characteristic feature of Ceramiales
Passive, non-flagellated sperm cells (spermatia)
In Polysiphonia sp.
The ______ produces the egg, and has an elongate terminal projection called the ______
Carpogonia
Trichogyne
Polysiphonia sp.
Fertilization results in a _____
Zygote divides to form ____
Carposporophyte enclosed in a haploid outer covering called ______
Diploid zygote
Diploid “carposporophyte generation”
Pericarp/cystocarp
Polysiphonia sp.
Carposporophyte remains attarched to the _______
Carposporophyte produced diploid _______
Carpospores are released through
Female gametophyte (haploid generation)
Carpospores bus mitosis in carposporangia
A small hole in the end of the cystocarp
Carpospores drift, settle and germinate into the ______
Terrapsporiphyte produces _____ in ____
Tetrasporangia (n) float away to establish ______
Second generation (tetrasporophyte generation)
Terrasporangia in filaments
New male and female gametophytes
Alternation of generations
Spends time as both diploid, multicellular, sporophyte and haploid, multicellular gametophyte
In coenobic colonies, daughter colonies have what number of cells?
Same number as parent colony
What is the function of increased surface area in algae?
-spines
-flat/ larger shape
Help to keep algae higher up in water column to allow for more light to create photosynthesis
Monoecious
Dioecious
Oogonia is and antheridia on same filament
Oogonia and antheridia on different filaments
Siphonous (coenocytic)
Long branch is the cell
Cell wall dissolved
What colours can red algae appear?
Green or red
What is the function of having a 3rd generation in Polysiphonia?
Since sperm are non motile, the fertilization that can occur is limited. Any fertilization that does happen is capitalized on. Reproduction of as many copies of the zygote, and as many carpospores as possible are made.
