Sam's Copy

CHLOROPHYTA

Characteristics• NUCLEUS- Uninucleate- Multinucleate- Cells are eukaryotic

• COLOUR- Green- Some may be red or orange

• FLAGELLATION- Vegetative and reproductive cells are motile - 2 or multiples of 2 flagella equal in length- No mastigonemes

• MORPHOLOGY- Unicellular flagellates- Colonial flagellates- Non-motile unicells - Non-motile colonies- Branched or unbranched filaments- Parenchymatous or siphonous thalli

• REPRODUCTION- vegetative: cell division, autocolony formation,

fragmentation- asexual: zoospores or autospores- Sexual: isogamous, anisogamous or oogamous- Resting stages: eukaryotic akinetes, may form thick

walls and become resting spores

• LIFE HISTORY- Zygotic- Sporic- Gametic

• CHLOROPLAST- 2 membrane envelopes- No PER- Thylakoids in stacks of several to many- DNA scattered- Starch is stored within the chloroplast- Conspicuous chloroplasts

• EYESPOT- Within the chloroplast but not associated with the flagella

Acrosiphonia sp.

Ploidy: N

Life History: Sporic heteromorphic

Codium fragile- Coenocytic- Dichotomously branched- multinucleate

Ploidy: 2n

Life History: Gametic

Codium Sporangia

Codium Utricle

Prasiola sp.

Ulva linza-Parenchymatous blade

Ulva intestinalis Tubular blade formation

Ulva lactuca Parenchymatous blade formation

Example of a Chlorophyte

Example of a Chlorophyte 2


Example of a Chlorophyte 4: Volvox sexual reproduction




Antheridium

oogonia

Chloroplast of a desmid-Note the pronounced stacking of the thylakoids-The 2 membranes of the chloroplast envelope and the scattered light areas containing fibrils of DNA- green algal chloroplasts are similar in many respects to those of high plants

ChlamydomonasUpper: diagrammaticLower: electron micrograph

Section through the eyespot of

Chlamydomonas-These eyespots may be one or several layers thick- they are located within the chloroplast but not close to the flagella- the eyespot operates by intercepting (shading) and/or reflecting (increasing the illumination) light onto the photoreceptor pigment, which is localized in either the plasma or chloroplast membranes over the eyespot- note the stacking of the thylakoids

Portions of sections through chloroplasts of

the Chlorophyta-This is the only algal phylum in which starch is stored in the chloroplast-It may be in a sheath surrounding the pyrenoid and/or in other parts of the chloroplast

Chloroplast of a ‘higher plant’-Compare to previous slide- note the arrangements of the thylakoids into grana stacks (dark areas) which are connected by stroma lamellae- the scattered areas containing chloroplast DNA (in between the grana stacks) (NA)- RUBISCO in higher plants is found in the stroma of the chloroplast (S)

RHODOPHYTA

Characteristics• NUCLEUS- Very small nuclei- Often multinucleate

• COLOUR- Pink, Red, Purple, Black, Bluegreen, Brownish

• FLAGELLATION- None

• MORPHOLOGY- Simple microscopic unicells- Branched filaments- Corticated filaments

– Corticating cells surround in clusters the main filament

- pseudofilaments- Polysiphonous filaments

– Polysiphonous cells arrange themselves like flower petals around the main axial cell by pitplugs

- Parenchymatous thalli- Large complex pseudoparenchymatous thalli

– Uniaxial pseudoparenchyma: 1 main filament with many coming off the sides

– Multiaxial pseudoparenchyma: many main filaments together with many coming off the sides

• REPRODUCTION- Cell division:

– Unicells undergo simple cell division– Filaments undergo cell division and

elongation which can be apical and/or intercalarly

- Sexual Reproduction:– Oogamous by fusion of spermatia (non

motile male sex cell) with a carpogonium (female reproductive organ)

• CHLOROPLASTS- Chlorophyll a- Unstacked thylakoids- 2 membranes around the chloroplast- Starch is the storage product- Stellate or discoid chloroplast shapes- Phycobilisomes present- Pyrenoids (centers of carbon dioxide fixation

within the chloroplasts) store RUBISCO- Chloroplast DNA Is scattered in nucleoids

• EYESPOTS- None

Characteristics Part 2• LIFE HISTORY• Sporic meiosis with an alternation of isomorphic or heteromorphic generations• Red algae:

– Male gametophytes (n) produce spermatia (non motile male sex cells)– Female gametophytes produce carpogonia (egg cells) that are retained on the female gametophyte plant– After fertilization the zygote (2n) stays on the female gametophyte and develops into a carposporophyte (2n)– This carposporophyte produces carpospores (2n) that are released and become tetrasporophytes– Each tetrasporophyte produces tetrasporangia where meiotic divisions result in tetraspores (n)

• Polysiphonia: Isomorphic

– Tetrasporophyte (2n)(small plant) is forming tetrasporangia (round balls)– These tetrasporangia divide into four parts four spores (n) are then formed– From these spores, male and female gametophytes form– Tetrasporophytes and gametophytes look identical– The spermatangia (male reproductive organs) are formed at the top of the branches of the gametophyte (look like small cucumbers) are crowded with

spermatia (non motile male sex cells)– Spermatia can melt together with the carpogonium (female reproductive organ also know as the oogonium)– Nucleus of the male cell moves through the tube of the trichogyne (hair like receptive protuberance of the carpogonium) to the egg cell and a zygote is

formed that develops into a cystocarp (fruiting structure with a special protective envelope produced after fertilization)– In the cystocarp, carpospores are formed (2n) which escape through a hole and the top and can grow into a tetrosporophyte

• Porphyra: Heteromorphic

– Conspicuous blades are gametophytes (n) that bear either spermatia or carpogonia or both– Fertilization occurs in the situ on the female gametophyte– The zygote remains in the female gametophyte blade and divides to form many carpospores (2n)– The carpospores are released and germinate to produce the “Conchocelis” stage (2n)– This stage burrows into shells (i.e. oysters and clams) and produces spores called conchospores – Conchospores form new thallus

• Mastocarpus: Heteromorphic• Female gametophyte (n) produce carpogonium (trichogyne + egg)• Male gametophyte produce spermatia (n)• Spermatia and carpogonia fuse to form carposporophyte (2n)• Carposporophyte forms carpospores (2n)• Carpospores are released and form tetrasporophyte (2n) • Tetrasporophyte form tetrasporangia and meitotically divide to form tetraspores (n) which then go back to forming the male and female gametophytes

Mastocarpus papillatus/Petrocelis

Mastocarpus – N (gametophyte)Life History: sporic heteromorphic life history

Petrocelis – 2N (tetrasporophyte)- Dark purple to nearly black

Mastocarpus Life Cycle

Mastocarpus

Petrocelis phase

Chondracanthus exasperatus

Mazzaella splendens-If there are cystocarps (N) present containing carpospores (2N) then it is a gametophyte (N)

- if these are not present then its a tetrasporophyte (2N)

- Life history: Sporic heteromorphic

Sparlingia pertusa

Ploidy: if there are bumps then it’s a gametophyte (N) with cystocarps; if not, then it’s a tetrosporophyte (2N)


Polysiphonia pacifica

Hildenbrandia

- Thinnest of the crusts- bright orange/red in colour

Gracilaria pacifica



Polyneura latissima



Grateloupia doryphora

Porphyra fallaxPloidy: N

Life History: Sporic Heteromorphic- Conchocelis stage is 2N

Example of a Rhodophyte: Polysiphonia

Example of a Rhodophyte 2: Porphyra

Example of a Rhodophyte 3: Hollenbergia

Conchocelis phase of Porphyra

PHAEOPHYTA

CHARACTERISTICS• NUCLEUS- Uninucleate - Eukaryotic

• COLOUR- Brown

• FLAGELLATION- Two heterokont flagella (only reproductive cells)- Long flagellum has 2 rows of mastigonemes - Shorter flagellum is smooth and directed backward- Has a light receptor- Attached laterally

• MORPHOLOGY- Multicellular- Sometimes very large- Unbranched filaments- Parenchymatous- Pseudoparenchymatous is rare- Have a meristoderm:

o small surface cells with chloroplasts and capable of division

- cortex:o general larger cells lacking chloroplasts

which do not divide- Medulla:

o trumpet hypae cells form

• REPRODUCTION- vegetative: formation of propagules or by

fragmentation,- Asexual: by zoospores formed in plurilocular

sporangia- Sexual: fusion of isogamous, oogamous

• LIFE HISTORY- Gametic:

o gametes range from oogamous to isogamous

- Sporic

• EYESPOT- In spores or gametes within the chloroplast and

associated with a flagellum- Present and acts as shading or light reflector

Characteristics Cont’d• CHLOROPLAST- One to many smooth chloroplasts- Storage product is stored outside the chloroplast- 4 membranes surround the chloroplast- 2 membrane envelope and PER- Thylakoids are in stacks of 3 - Girdle lamella is present

• OTHER- DNA is ring shaped- RUBISCO in the pyrenoids- Cell wall always present – made of cellulose, alginic

acid and polysaccharides- Sieve elements: perforated cross walls in large kelps

for conduction of photosynthate

Fucales: Sargassum muticumPloidy: 2N

Life History: Gametic meiosis forms gametes which fuse to form a diploid zygote that grows into the adult plant

Other: has short stubby receptacles that bear oogonial and antheridial conceptacles

Fucales: Fucus gardneriPloidy: 2N

Life History: gametic meiosis forms gametes which fuse to form a 2N zygote that grows into the adult plant

Other: parenchymatous thalli with apical meristems

Anatomy: meristoderm, cortex and medulla present- Receptacles (ends of blades) contain pores (small depressions) under which are conceptacles (spaces) within which are oogonia, antheridia or both

Fucus Life Cycle

Chloroplast of Fucus

Fucales: Pelvetiopsis limitata

Ploidy: 2N

Life History: Gametic meiosis forms gametes which fuse to form a diploid zygote that grows into the adult plant

Melanosiphon intestinalis

Ralfsia- Dark brown or yellowish brown

Scytosiphonales: Petalonia fascia

Ploidy: N (crusts are diploid sporophytes)

Life History: Sporic

Other: Growth is diffuse

Scytosiphonales: Scytosiphon lomentaria

Ploidy: N (crusts are diploid sporophytes)

Life History: Sporic

Other: growth is diffuse

Laminariales: Saccharina latissima

Ploidy: 2N

Life History: Sporic Heteromorphic, with microscopic filamentous gametophytes

Laminariales: Nereocystis luetkeana

Ploidy: 2N

Life History: Sporic heteromorphic with microscopic filamentous gametophytes

Sieve elements of Nereocystis

-Sieve elements are elongated cells located with in the medulla

- their cross-walls have fields of pored with plasmodesmata

- used for translocation of photosynthate

Laminariales: Macrocystis pyrifera

Ploidy: 2N


Laminariales: Saccharina sessilisPloidy: 2N

Life History: Sporic Heteromorphic with microscopic filamentous gametophytes

Laminariales: Alaria sp. Ploidy: 2N


Laminariales: Costaria costataPloidy: 2N


Laminariales: Egregia menziesiiPloidy: 2N


Laminariales Reproduction

Desmarestiales: Desmarestia acuelata

Ploidy: 2N


Other: trichothallic meristem (at the base of hair) which produces a pseudoparenchymatous uniaxial thallus

** only pseudoparenchymatous brown

Desmarestiales: Desmarestia sp.

Ploidy: 2N


Other: trichothallic meristem (at the base of hair) which produces a pseudoparenchymatous uniaxial thallus

** only pseudoparenchymatous brown

Plurilocular: found in Ectocarpales

-Plurilocular gametangia that release hundreds of isogametes

- each gametophyte (plant) are N and produce gametes by mitosis

Unilocular: found in Ectocarpales-Unilocular sporangia with 2N cells that undergo meiosis to produce unicellular N zoospores

- borne on the diploid plant

- this thallus is called the sporophyte

- the meitotically produced zoospores grow by mitosis into gametophytes

Location of chloroplast DNA in the Phaeophyta

Left: is a perpendicular section through a disc-shaped chloroplast, showing sections of the ring nucleoid beneath the girdle lamella, at both ends

Right: is a section parallel to the face of the same chloroplast, showing the entire ring of DNA

Diagram of a brown algal cell

Pyrenoids of a brown algal cell

Spermatangia

Polysiphonous

Heterocysts

Pennate Centric

Girdle VIew Valve View

Geminata

Diatom Silica wall formation

Volvox Gonidium

Oogonia

Antheridia

Heterocyst & Akinete

akinete

heterocyst

CRYPTOPHYTA

Characteristics• NUCLEUS- Eukaryotic- Uninucleate

• COLOUR- Red- Tan- Blue-green- olive

• FLAGELLATION- 2 similar flagella both with mastigonemes- Flagella are apical or lateral and originating within a

groove

• MORPHOLOGY- Unicellular

• REPRODUCTION- Vegetative: by cell division- Sexual: not well known

• LIFE HISTORY- Not well known

• CHLOROPLAST- 1 to 2 smooth chloroplasts- Thylakoids usually in stacks of 2- Chlorophylls a and c- Phycobilins present- Chloroplast DNA in scattered nucleoids- 4 membranes around chloroplast- Eyespots when present are within the chloroplast but

not associated with the flagella

• OTHER- Have protein plates that act as an anchoring system

and is internal to the plasma membrane- Ejectosomes line the gullet- Storage product is starch and is stored outside the

chloroplast envelope, inside the PER

Example of a Cryptophyte

Flagella

ejectosomes

Plastids

A Cryptophyte eyespot-These eyespots may be one or several layers thick- they are located with in the chloroplast but not close to the flagella- the eyespot operates by either intercepting light (shading) or reflecting light (increasing the illumination) onto the photoreceptor pigment- which is probably localized in either the plasma membrane or chloroplast membranes over the eyespot

Electron micrograph of a cryptophyte

-The large ejectosomes seen here line the wall of the gullet-Part of a smaller ejectosome is visible just beneath the plasmalemma on the lower left side of the cell

Diagram of a longitudinal section of a cryptophyte

DINOPHYTA

Characteristics• NUCLEUS- Nucleus with condensed chromatin at interphase

• COLOUR- Brownish- Golden-brown- Red-brown- Can be colourless

• FLAGELLATION- 2 highly heteromorphic flagella originating near each

other- One is flattened and wraps around the cell- Other flagellum trails behind


• REPRODUCTION- Vegetative: cell division- Sexual: by fusion of isogamous or anisogamous

gametes

• LIFE HISTORY- Zygotic

• CHLOROPLAST- 3, 4 or 5 membranes around the chloroplast- Chlorophylls a and c- No phycobilins- Thylakoids in stacks of 3- Scattered DNA

• EYESPOT- Present or not

• OTHER- Storage product is outside the chloroplast and may

form a cap over the pyrenoid- Cell wall internal if present- Has a girdle- Has a sulcus- Hypotheca is located posterior on area that has the

sulcus- Epitheca is apical- Covered by a theca subdivided into plates with or

without cellulose horns or spines may form

Example of a Dinoflagellate

girdle

theca

Horns off the theca

Trailing flagellum

Example of a Dinoflagellate 2

sulcus

Displace girdle

Example of a Dinoflagellate 3

Ventral View: sulcus and girdle

Dorsal View: girdle onlyIs flattened therefore has jerky swimming motion

Interphase nucleus and chromosomes of a

dinoflagellate-The chromosomes lack histones, are permanently condensed and have a characteristic banded appearance

-There is a large nucleolus within the nucleus

EUGLENOPHYTA

Characteristics• NUCLEUS- Uninucleate- Eukaryotic- Chromosomes are condensed during interphase

• COLOUR- Bright green - Colourless

• FLAGELLATION- 2 heteromorphic flagella originating with in a reservoir

(gullet?)- Usually only one is emergent- Some species do possess 2 or 4 emergent flagella


• REPRODUCTION- vegetative: cell division

• CHLOROPLAST- Chlorophylls a and b- No phycobilins- Store paramylon which is similar to starch- 3 membranes around the chloroplast- Thylakoids in stacks of 3- Smooth and variable in shape and number

• EYESPOT- Present usually in photosynthetic form- It is large, anterior, near the reservoir - Not located in the chloroplast- Associated with flagellar swelling

• OTHER- Cell wall consists of interlocking protein strips- Can rapidly change shape (known as metaboly) only

in some species

Example of an Euglenophyte

Colourless (due to lack of chloroplasts); Exhibit a large range of shape changes (metaboly)

Paramylon bodies

Example of an Euglenophyte 2

Example of an Euglenophyte 3

Show no metaboly

Euglena longitudinal section

- Note the distinctive outer covering, the pellicle

Interphase nuclei of a green alga and a

euglenophyte-Note the condense chromosomes of the euglenophyte

Euglena- Diagrammatic longitudinal section

Eyespot of a euglenophyte-The eyespot is composed of loosely packed globules lying outside the chloroplast, next to the reservoir, opposite of the flagellar swelling- the swelling is usually on the longer, emergent flagellum and is thought to be the site of the photoreceptor pigment

Sections through parts of chloroplasts from 3 algal

groups-upper photo: chrysochromulina (haptophyte)-PER surrounds chloroplast- chloroplast envelope has 2 membranes

-Middle photo: dinobryon (chrysophyte)- has a girdle lamella - PER surrounds chloroplast- chrloroplast envelope has 2 membranes

- lower photo: trachelomonas (euglenophyte)- chloroplast envelope has 3 membranes

-All three groups share stacking of thylakoids in three

HAPTOPHYTA

Characteristics• NUCLEUS- Uninucleate- Small eurkaryotic

• COLOUR- Golden brown

• FLAGELLATION- 2 equal flagella with a third flagellum-like appendage

between them haptonema- Originate near each other at the apical end of the cell


• REPRODUCTION- vegetative: cell division- Sexual: not well known

• LIFE HISTORY- Not well known

• CHLOROPLAST- Chlorophylls a and c- No phycobilins- 4 membranes around the chloroplast- 1 or 2 chloroplasts present- Thylakoids in stacks of 3- 2 membrane PER- No girdle lamella

• EYESPOT- Found in some members- Located within the chloroplast

• OTHER- Cell coverings has organic scales- Some species have calcified scales (coccoliths)

Example of a Haptophyte

Haptonema

**The haptonema functions as a food gathering device and in others as a sensory or attachment mechanism may be coiled or fully extended

Outer view of a haptophyte

- The cell surface is completely encased in coccoliths , special organic scales encrusted with calcium carbonate

Electron micrograph of Chrysochromulina

- This photograph shows the two flagella and a haptonema, the latter lightly coiled at the tip

Several cross-sections through a haptonema

- Note the outer sheath of three concentric membranes and the inner circle of 6 or 7 microtubules

Sections through parts of chloroplasts from 3 algal

groups-upper photo: chrysochromulina (haptophyte)-PER surrounds chloroplast- chloroplast envelope has 2 membranes

-Middle photo: dinobryon (chrysophyte)- has a girdle lamella - PER surrounds chloroplast- chrloroplast envelope has 2 membranes

- lower photo: trachelomonas (euglenophyte)- chloroplast envelope has 3 membranes

-All three groups share stacking of thylakoids in three

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