4 per page

Groups (Kingdom)
DOMAIN
1.Bacteria- cyanobacteria (blue green algae)
2.Archae
3.Eukaryotes
Division: Rhodophyta
“Algae”
1. Alveolates- dinoflagellates
2. Stramenopiles- diatoms, Ochrophyta
3. Rhizaria- unicellular amoeboids
4 Excavates- unicellular flagellates
4.
5. Plantae- rhodophyta, chlorophyta, seagrasses
6. Amoebozoans- slimemolds
7. Fungi- heterotrophs with extracellular digestion
8. Choanoflagellates- unicellular
1
9. Animals- multicellular heterotrophs
2
Algal Evolution:
Unicellular, freshwater
Chloroplast peptidoglycan
Plantae
3.9 bya = Cyanobacteria appear and introduce photosynthesis
Glaucophytes
Rhodophyta
Chlorophytes
phycoerythrin
Chl b,
starch
Charophytes
Land Plants
2.5 bya = Eukaryotes appeared (nuclear envelope and ER thought to come
from invagination of plasma membrane)
1.6 bya = Multicellular algae -Rhodophyta (Red algae) &Chlorophyta
(Green algae)
y Dinoflagellates
g
& Invertebrates appear
pp
900 mya=
490 mya = Phaeophyceae (Brown algae) & land plants & coralline algae &
crustaceans & mulluscs
408mya= Insects & Fish
362 mya = Coccolithophores & Amphibians & Reptiles
290mya- Gymnosperms
3
Adapted from Sadava 2014
145 mya = Diatoms & Angiosperms
1
Division Rhodophyta
- most speciose of the macroalgae
Location
Red
Brown
Green
S. Australia
800 (70%)
231
123
1154
7,117 species identified
(up to 20,000 ?!?)
98% marine
N. Atlantic
589 (50%)
324
258
1171
Biogeography/distribution
• Found at all latitudes
W.USA
459 (69%)
137
72
668
•Tropical- small & filamentous
• Temperate
 highest # of spp (outnumber browns and greens)
• Polar
 relatively few species – browns and greens dominate
 lots of crustose coralline reds, to 200 m
• Size distribution
 tropical = mostly small filamentous plants (except calcareous
forms)
 temperate = larger fleshy species
5
Rhodophyta Characteristics
Algal taxonomy
1) Pigments: chl a & d
carotenoids: B-carotene, A-carotene
Hierarchical system of classification:
phycobilins: phycocyanin, phycoerytrin, allophycocyanin
2) Plastid structure:
• envelope: 2
• thylakoids: single, no stacks, covered with phycobilisomes
3) Storage product: floridian starch, doesn’t stain with IKI
Level:
Domain
Group
Division
Class
Subclass
Order
Family
Genus
species
4) Flagella: none
5) Life History: Alternation of Generations Only
Mitosis: closed, no centrioles
6
7
suffix:
-phyta
p y
-phyceae
-phycidae
-ales
-aceae
example:
Eukaryote
Plantae
Rhodophyta
Florideophyceae
p y
Rhodymeniophycidae
Rhodymeniales
Rhodymeniaceae
Rhodymenia
pacifica
8
2
Pigments
Phycobilisome structure:
Allophycocyanin
9
10
…vs. other divisions: pigments imbedded within the
thylakoid membrane
Phycobilisome on the
thylakoid membrane
Structure of
phycoerythrin +
protein
11
12
3
Rhodophyta Pigments
Pigments
Experiment:
- same species of red algae
- place on rope at 3 depths
Buoy
Reds respond to changing light conditions by:
1.
Red light
Changing the number/density of phycobilisomes
2. Changing
g g the # of molecules of pigment
pg
in each antennae
…what is this called?
Green light
13
Pigments
Rhodophyta: Morphology of Cell Walls
(Extracellular Matrix or ECM – less rigid than other
algae/plants)
Experiment:
- same species of red algae
- place on rope at 3 depths
Buoy
14
Two Main Components:
PC
1. Cellulose  microfibrils for structural support
2. Phycocolliods- Mucilaginous polysaccharides that surround
microfibrils (more abundant than microfibrils)
a. agar/agarose
b. carageenan (after Irish Co b/c Chondrus crispus)
Function: elasticity/flexibility (cope with water motion),
desiccation prevention, osmoregulation (ion exchange),
dispersal/motility?, fusion with other cells, wound repair,
parasitism, increases in length/volume, attachment
PE
15
16
4
Rhodophyta Cell Characteristics:
large cells due to:
Human Uses of Rhodophyta
• Food
• nori (Porphyra)
• 1949 life cycle completed – advanced cultivation techniques
1. Multinucleate = one cell has multiple nuclei
# of nuclei correlated to the number of plastids
(replication, mitosis, no cytokinesis)
• Phycocolliods = dervived from mucilagenous polysaccharides of cell
walls
•Thickeners
•Stabilizers
•Gels
•Two important phycocolliods:
• Carageenan (toothpaste, cosmetics, chocolate milk, ice cream,
dessert gels, pet foods), found in Chondrus, Gigartina, Eucheuma
and Kappaphycus
•Agar (food gel, pharmaceutical capsules, medium for culturing
microorganisms, gel electrophoresis), found in Gelidium,
Gracelaria, Pterocladia, and Ahnfeltia
17
18
Cell characteristics
Cell characteristics
Apical cell:
yp
y repeated
p
genome
g
duplication
p
2. Polyploidybuffer against mutation of essential genes
(Endoreduplication = replication, no mitotic
nuclear division)
Multinucleate
non-polyploid
Uninucleate
non- polyploid
Uninucleate
polyploid
Uninucleate
non- polyploid
Uninucleate, polyploid
Apical cell:
Derived
cells:
Uninucleate
non- polyploid
Multinucleate
non- polyploid
Uninucleate
polyploid
Multinucleate
non- polyploid
Multinucleate
non- polyploid
Derived cells:
Examples:
19
Multinucleate,
non- polyploid
Mazzaella,
Callithamnion,
Chondracanthus
Uninucleate
polyploid
Microcladia
Multinucleate
non- polyploid
Polysiphonia
20
5
Pit plugs
- structural support between cells
Pit plugs
- structural support between cells
Old name: “pit connections”
• Protinaceous plugs between cells
• Secondary pit plugs 
formed between non
non-related
related
cells within and individual
among filaments or between
individuals (parasites)
• Primary pit plugs
 formed
f
dd
during
i cytokinesis
ki
i between
b
2 daughter cells within a filament
• Not a real connection – unlike browns,
not for transport
21
22
Polysiphonous – composed of tiers of vertically elongated
cells, transversely arranged, the lateral cells around a
central axis (siphon)
Rhodophyta Morphology
-Unicellular- solitary non motile cells
central filament surrounded by 4 or more pericentral cells
MAC Key: Cells in a regular transverse series
- Filamentous- chain of cells
-Parenchymatous- undifferentiated,
undifferentiated
isodiometric cells generated by a meristem
- Pseudoparenchymatous- form of thallus
composed of interwoven continuous filaments
23
Polysiphonia
24
6
Cortication : elaboration of polysiphonous condition where
pericentral cells continue to proliferate
Growth
Reds often display growth through cell elongation
Cell repair by cell fusion
New growth = not florescent
Partial Cortication
25
26
Uniaxial Growth- one longitudinal central filament forming the
axis
Heterotrichous Growth
– filamentous growth in 2 directions, results in thallus composed of
both prostrate + erect components
Intercallary meristem
= cell division
Epithallus
Parithallus
hypothallus
Apical meristem
27
28
7
Multiaxial Growth- several longitudinal medullary filaments,
each derived from an apical cell
Flagella? NO - lack of flagella has led to…
TRIPHASIC LIFE HISTORY
• Spores – no flagella
• Gametes – no flagella
• “Spermatia”
“S
i ” = unflagellated
fl
ll
d male
l gametes; no free
f
movement
• Passive dispersal by water
29
Has led to adaptations that allow survival during
seasonal variation in habitat and herbivory pressure…
(Some herbivores prefer eating one life history
30
stage over another)
Division: Rhodophyta- 6504 species
1. Class: Porphyridiophyceae -12 species
Order: Porphyridales
Division: Rhodophyta- 7,117 species
• Unicellular
• “a little round thing”
• Soil, Arial habitats, Fresh water,
Brackish, Marine
Eight
Ei
ht classes
l ss s
Focus on 3 classes:
1. Class: Porphyridiophyceae -12 species
2.Class: Bangiophyceae-197 species
3.Class: Florideophyceae- 6,767 species
•Surrounded by a mucilaginous
sheath
• Large stellate chloroplast
• Reproduction by cell division,
release of vegetative cells or by
endospores
31
Genus: Porphyridium, Rufusia
32
8
Division: Rhodophyta- 6504 species
Class: Porphyridiophyceae -12 species
Order: Porphyridales
Genus: Porphyridium
Division: Rhodophyta- 6504 species
1.Class: Porphyridiophyceae -12 species
Order: Porphyridales
Genus: Rufusia
Found only in sloth hair
33
34
Genus: Bangia
Division: Rhodophyta- 6504 species
2.Class: Bangiophyceae-158 species
Order: Bangiales
- “simple” reds
• Unbranched uniseriate filament in early
development; later becomes multiseriate;
rhiziodial extensions of lower cells
- unicells, filaments, parenchymatous blades
- marine, terrestrial, freshwater
•2N conchocelis stage
g like Pyropia
y p
- uninucleate
uninucl t
-one stellate chloroplast per cell
•Asexual reproduction by monospores
- pit plugs rare; if present, only primary, and in 2N stage
• Pit plugs present in conchocelis stage
but not in gametophyte
- biphasic life history
Genus: Bangia & Pyropia
•Inhabits upper intertidal splash zone on
rocks – rarely epiphytic
35
36
3
6
9
Genus: Pyropia (Porphyra)
Algal Life Histories :Terminology
1N gametophyte:
 parenchymatous blade
 monostromatic or distromatic
Spermatium, spermatia (pl) = a non motile cell that
functions as a male gamete
Carpogonium = female gamete
2N sporophyte:
 “conchocelis” stage
 discovered in 1949 by Kathleen
Drew Baker
B k
 REVOLUTION
E
 microscopic filament
 lives on/in mollusk shells
 perennial
Conchocelis stage= 2N filamentous stage; lives in/on CaCo3 shells of mollusks
Conchospore = 1 N spore produced by 2N conchocelis stage
Monospore= 1N or 2N asexual spore that develops into the same phase as the
parent
• Haplodiplontic life history
• Saxicolous or epiphytic/endophytic
• Harvested for nori
Asexual vs. Sexual: gametophyte switches from monospores to gametes;
triggered by daylength (fall = shorter days = sex)
37
38
Division: Rhodophyta-
Life History of Bangaliales ex Pyropia
Haplodiplontic Alternation of Generations: organism having a
separate multicellular diploid sporophyte and haploid gametophyte stage
2.Class: BangiophyceaeOrder: Bangiales
syngamy
Mt
Spermatia from male
gametophyte
spermatium
Mt
p g
carpogonium
2N carpospores
carpogonium
microfilamentous
2N conchocelis stage
1N
gametophytic
macrothalli
Mt
meiosis occurs in
conchosporangium
fertilization
plantlet
Me
Capogonium divides to
form carposporesNo gominoblast
1N conchospore
Mt
monospore
monospore
39
gametophyte
40
10
Division: Rhodophyta- 6504 species
Triphasic Life History
3.Class: Florideophyceae-6199 species
1) Gametophyte: haploid, 1N multicellular releases gametes
- advanced reds
- always multicellular: filaments or psuedoparenchymatous
-marine, freshwater
2) Carposporophyte: all 2N material on the female gametophyte
where the 2N zygote is cloned to form the carpospores
releases carpospores
3) Tetrasporophyte: diploid, 2N multicellular
releases tetraspores
-almost always multinucleate
-many discoid chloroplasts
-primary and secondary pit plugs
- triphasic life history
41
1N gametophytes
2N carposporophyte
on 1N female gametophyte
Multiple 2N carpospores
produced through mitosis in
gominoblast filaments
mitosis
1N
42
Triphasic Life Histories :Terminology
trichogyne
Female Gametophyte-hapliod, 1n, multicellular produces gametes
Carpogonial branch (cb)= filamentous branch on
which the carpogonium are formed
cp
cb
Carpogonium (cp) =female gamete
2N
Carpogonium on a
carpogonial branch
1N
2N carpospores
Trichogyne = extension of egg to which
spermatium attaches
Male Gametophyte-hapliod, 1n, multicellular release gametes
1N
Spermatangial branch = filamentous branch
which holds the spermatangia
meiosis
growth
1N tetraspores
Spermatangium, Spermatangia-male
reproductive structure that
produce spermatia
2N
43
2N tetrasporophyte
Spermatia= male gamete
44
11
1N gametophytes
Triphasic Life Histories :Terminology
2N carposporophyte
on 1N female gametophyte
spermatia
Male gametophyte - Polysiphonia
Multiple 2N carpospores
produced through mitosis in
gominoblast filaments
tricoblasts
mitosis
1N
2N
tricogyne
Carpogonium on a
carpogonial branch
spermatangia
Female gametophyte - Polysiphonia
1N
1N
meiosis
growth
Trichoblast = usually a uniseriate filament of cells (with little
pigmentation) that either remains sterile or can undergo division to
form either spermatangia or carpogonium.
1N tetraspores
2N
46
2N tetrasporophyte
45
Triphasic Life Histories :Terminology
2N carpospores
1N gametophytes
2N carposporophyte
on 1N female gametophyte
Carposporophyte = diploid, multicellular, one of the 2N generations; develops from
the fusion of the carpogonium & spermatium (all 2N material on the female
gametophyte); this is where the 2N zygote is cloned to form the carpospores
Multiple 2N carpospores
produced through mitosis in
gominoblast filaments
Pericarp = 1N vegetative tissue that surrounds the carposporophyte
mitosis
Cystocarp = pericarp (1N) + carposporophyte (2N).
1N
Carposprorangia = reproductive structures that produce carpospores
2N
Gonimoblast = 2N filaments bearing carposporangia in the carposporophyte
Carpogonium on a
carpogonial branch
Carpospore = dipliod (2n) spore formed by mitosis by the carposprophyte
1N
2N carpospores
1N
meiosis
growth
2N
1N tetraspores
1N
47
2N
48
2N tetrasporophyte
12
( )
Carpospoophyte (2N)
Mt
Mt
(
( )
)
( )
Gametophyte (1N)
Carpospores (2N)
Gametophyte (1N)
Me
( )
Tetraspores (1N)
Tetrasporophyte (2n)
( )
Mazzaella
Triphasic Life Histories :Terminology
Tetrasporophyte = diploid, multicellular, one of the 2n generations; develops from
germinating carpospore
&
release tetraspores
Tetrasporangium = 2N cell which undergoes meiosis to form 4 tetraspores
Tetraspore = haploid (N) spore formed by meiosis by the tetrasporophyte
types of tetraspore arrangement within the tetrasporangia
(four 1N spores)
Tetrahedral
Cruciate
(two views)
1N gametophytes
Zonate
51
2N carposporophytes
on female gametophyte
2N tetrasporophyte
52
13
Mastocarpus species complex
2N carposporophytes
on female gametophyte
1N gametophytes
2N tetrasporophyte
53
14