Heterokontophyta Flashcards
Algae in Chrysophyceae can be ______, _______ or ______
Unicellular, colonial, filamentous
Pigmentation of Chrysophyceae
Predominant pigments: fucoxanthin, Dinaxanthin, diadinoxanthin, b-carotene
Chlorophyll a and c (no b)
Pigments of Chrysophyceae are contained where?
Chloroplasts with outfoldings of nuclear membrane
Thylakoid structure in Chrysophyceae
Thylakoids within chloroplasts are grouped into 3’s with no granal stacks
Outer covering of Chrysophyceae
Vary: naked protoplasts, cells with ornate scales, closely attached walls or overlapping valves
Principle food reserved of Chrysophyceae
Carbohydrates
Asexual reproduction of Chrysophyceae is by means of
Binary fission, fragmentation or sporulation (zoospores or autospores) or testing spires (statospores)
Sexual reproduction in Chrysophyceae is usually ______ with ______ meiosis
Isogamous
Zygotic
Ochromonas sp.
-taxonomy
-habitat
-lifestyle
-structure
-appearance
Class Chrysophyceae
-planktonic or benthic in cold waters
-photo autotrophs or heterotrophs
-unicellular, naked forms
-2 dissimilar flagellae, parietal chloroplasts, eyespot and contractile vacuole
Synura
-taxonomy
-claim to fame
-lifestyle
-appearance
Class Chrysophyceae
-undesirable taste on drinking water
-motile, spherical colony
-biflagellate, taped towards the center of the colony
Dinobryon
-taxonomy
-lifestyle
-appearance
-what does it do
Class Chrysophyceae
-dendroid colony of Loricate cells. Each cell within the lorica is biflagellate.
-foul or fishy odour to water
Class Bacillariophyceae are known as?
Diatoms
Class Bacillariophyceae
Vegetative cells are typically ______ and ______
Unicellular
Non motile
Class Bacillariophyceae
The two overlapping valves (_____) are made of ______ with an organic coating and cover membrane-bound protoplasm
Frustules
Silica
Class Bacillariophyceae chloroplast structure
Vary from being several discoid chloroplasts per cell to single large Stellate or band-shaped structures
The predominant of carotenoid pigments in Class Bacillariophyceae imparts a ____________ to _________ appearance to the cells
Golden brown
Yellow green
Reproduction in Class Bacillariophyceae
-binary fission
-during mitosis, the two valves of the frustule separate, the protoplasm divides longitudinally and the innermost or hypothecal valve is replaced in each new daughter cell
-to compensate for this reduction, the cells periodically shed both of the valves, increase in sauce and synthesize two new valves.
The vegetative state of Class Bacillariophyceae is ______
Diploid
Sexual reproduction in Class Bacillariophyceae
Centric forms are oogamous and pennate forms are isogamous
Diatoms environment
-marine and freshwater
-planktonic and benthic
How is Class Bacillariophyceae divided
- Centrales or somewhat radial forms
- Pennales or elongate forms
Shapes determined from top of the valves (valve view). The side view is termed (girdle view)
Cyclotella sp.
-taxonomy
-type of diatom
Class Bacillariophyceae
Order Centrales
-centric diatoms
Melosira sp.
-taxonomy
-type of diatom
-appearance
Class Bacillariophyceae
Order Centrales
-centric
-chains of cells by failing to separate after cell division. Chains are joined at the valve tops, so the chain appears as rectangular cells in girdle view
Tabellaria sp.
-taxonomy
-type of diatom
-appearance
Class Bacillariophyceae
Order Pennales
-pennate
-joined at the corners of the cells to give the appearance of a long zig-zag chain
Synedra sp.
-taxonomy
-type of diatom
-appearance
-habitat
Class Bacillariophyceae
Order Pennales
-Pennate
-long pennate diatom where cells occur singly
-planktonic and benthic species
Diatomaceous earth
Mined from ancient deposits of marine diatoms. All that remains of the cells is the silica frustules, but these are extremely useful in a number of commercial ways such as abrasives and filters
Pennate and centric forms
Class Phyaeophyceae common name
Brown algae
The larger, macroscopic algae belong to one of two groups:
-used for what?
-grow where?
Class phaeophyceae
Phylum Rhodophyta
Vast majority of seaweeds
Enormous geological range-tropical to arctic waters, few are freshwater
Members of Class Phyaeophyceae are primarily living where?
Marine macro-algae
Few freshwater
Basic unit of organization of Class Phyaeophyceae
Filament
Brown colour of Class Phyaeophyceae is due to what
Making effects of chlorophyll’s by carotenoids and xanthophyll pigments (mainly fucoxanthin)
Class Phyaeophyceae, contains orders that can be organized according to their life cycles:
Isogenerate: exhibit isomorphic alternation of generations
Heterogenerate: exhibit heteromorphic alternation of generations
Cyclosporae: do not exhibit alternation of generations
Order Ectocarpales
-life cycle
-appearance
-anchorage
-isogenerate life cycle
-branched filamentous (thalli) forming bushy organisms from a few to 15cm in length.
-horizontal rhizoid-like structure penetrate the substrate for anchorage
Life cycle of Ectocarpus
-haploid and diploid phases are both filamentous
-diploid individuals produce unilocular meiosporangia; these are sporangia which produce meiospores (zoospores). The diploid individuals also produce plurilocular sporangia (many chambers) in which each chamber produced one “swarmer”
-The gametophyte produces only plurilocular structures. These could be zoosporangia, producing asexual zoospores, or gametangia, producing flagellated isogametes
-nuclei of unilocular mother cells divide meiotically to produce haploid zoospores. These are about twice the size of the gametes produced by haploid plurilocular sporangia. These haploid zoospores germinate to produce haploid gametophytes. Since the diploid sporophytes and the haploid gametophytes look the same, we can say that is is an example of isomorphic alternation of generations
Motile gametes are all the same size. Females settle down on the substrate and chemically attract male gametes, which fuse with them to form a zygote (2n). These zygotes develop in to the diploid plants
Asexual reproduction in Ectocarpus
-plurilocular sporangia of diploid generation produce diploid zoospores by Mitosis. These germinate into sporophytes, just like the parents. Haploid gametophytes also produce plurilocular structures. The plurilocular structures on the gametophyte are smaller than those of the sporophyte, they can produce either zoospores, or gametes (all by mitosis)
Order Laminariales
-life cycle type
-common name
-anatomy of kelp
-heterogenerate life cycle
-kelp
-holdfast, stipe, and blade region
Laminariales have well-defined areas of cell division meristematic regions within their _____
Blade regions
Leo’s have strands of elongated __________ in the Center of the ______ that are similar to ______. These cells have _______ similar to those of vascular plants
Conducting cells
Stipe
Phloem
Sieve plates
Marine algae do not need a mechanism for water transport and therefore there are no cells analogous to ______ or _____
Trachieds
Vessel elements
Morphology of Laminaria sp.
-distinct alternation of generations
-sporophytes are large and long-lived (blades up to 100m). Are parenchymous with growth from an intercalary meristem between the stipe and the blade, which adds tissue to both.
-gametophytes are much smaller and filamentous
Sexual reproduction in Laminaria sp is ________
Oogamous
Holdfast
Site of firm attachment of the kelp to the substrate by the growth of rhizoidal cells from the outer meristematic cells.
These rhizoidal cells fill every microscopic crevice of the substrate until an exact profile of the substrate is built.
3 tissue regions found in the sporophyte of Laminaria
Central medulla
Cortex and epidermis
At the thallus surface are the ________, _______ cells of the meristoderm, which add to the girth of the organ in Laminaria so
Photosynthetic
Meristematic
Life cycle of Laminaria sp.
Along length of the blade are found regions of epidermis called “sori”. These spring are composed of unilocular sporangia, intermingles with sterile “paraphrases” (filamentous strucures found packed between sporangia or gametangia). The unilocular meiosporangia produce 32 haploid meiospres. These meiospores settle to the substrate and produce the small filamentous gametophyte generation. The male gametophytes form mall colourless antheridia, that produce motile, biflagellate sperm. The females form elongated Oogonia. A single egg is released from the oogonium prior to fertilization. After fertilization, the zygote germinates to form a flat pro-embryo that subsequently differentiates into the mature sporophyte
Order Fulcales
-life cycle
-structure
Cyclosporae-haploid generation being reduced to eggs and sperm. The
remainder of the lifecycle is diploid.
-parenchymous with growth from an apical cell
Fucus sp.
-taxonomy
-appearance
Class Phaeophyceae
Order Fucales
-thallus is branches and supported by a short narrow stalk that is attached to a discoid holdfast. The branching is dichotomous and each branch has an apical cell that divides several times a year resulting in the formation of a dichotomy or fork.
Internal anatomy of Fucus
-mucilaginous cuticle covering the epidermal layer of cells
-inner cortex, with the medulla in the Center.
In Fucus, when vegetative tissues are damaged, cells of the exposed tissue divide to form a _____________
callous-like layer that differentiates into the adventitious branches
In Fucus, gametangia are formed in specialized hollow chambers called….
These are found embedded in ……
Conceptacles
Fertile areas called receptacles located at the tips of the branches of the sporophyte
Gametangia in Fucus
Oogonia and antheridia
Individuals of Fucus can be _______ or _______
Monoecious
Dioecious
Antheridia and Oogonia of monoecious species of fucus can be located in ……
The same or in separate conceptacles
Meiosis, which occurs within the _____, is immediately followed by ______ to give _____eggs per oogonium.
Similarity, ______ follows _____ in the _______ producing _____ sperm
Eventually the eggs and Sperm…….. where fertilization occurs
Fucus sp.
Oogonium
Mitosis
8
Mitosis
Meiosis
64
Set free int the water
Fucus
The small bumps on the surface of the receptacles are ________ which are….
Ostioles
Opening to the conceptacles
What type of meiosis is Fucus do undergoing
Gametic
Medulla
Conducting area
Perforated sieve plates to conduct sugars
Intercalary meristem
Between blade and stipe, extends height
Function of cortex, medulla and meristoderm
Cortex: parenchymous
Medulla: conducting
Meristoderm: photosynthetic and meristematic
Pneumatocysts
Air bladder of fucus sp
