Midterm Flashcards
Compare these 2 diatom types (centrics and pennates) based on the following characteristic:
- marine or freshwater? phytoplankton or benthos?
- Centrics: Primarily marine phytoplankton.
- Pennates: Freshwater (primarily) and marine, phytoplankton and benthos
Describe this algal storage product: Glucose.
- How is it produced? Is it used immediately or stored, and how?
- Produced by dark fixation of CO2 and energy products of light reactions (photosynthesis)
- May be used immediately to meet energy requirements of the cell
- Organism may store into glucose polymers (High molecular weight compounds or Low molecular weight compounds)
Xenic
presence of foreign organism in a culture
- good exam question *
Compare these flagella types: isokontous, heterokontous, haptonema.
- Isokontous: Flagella (more than 1) that are similar in length and type.
- Heterokontous: Dissimilar flagella (more than 1), of unequal length, and/or one smooth and one hairy (“tinsellated”).
- Haptonema: Superficially resembles flagellum but different internal anatomy (no 9+2 microtubular structure).
- function uncertain but may be used for defence, food capture, or attachment.
- exclusive to Division Haptophyta.
Algae are distributed in virtually every environment on earth. In terms of aerial/terrestrial environments, define this possible habitat:
- Epixylon
On wood surface (ie. wet tree)
Describe what Beta-methylamino-L-alanine (BMAA) is, which is produced by cyanophyta.
- Effects?
- Where is it produced/how?
- What is a population of interest in studying this, and why?
- An amino acid that can be incorporated into the body.
- Research says BMAA may be connected to degenerative nerve diseases like ALS, Alzeimer’s, and Parkinson’s.
- BMAA is produced by cyanobacterial endosymbionts of cycad roots in Guam.
- Connection with neurodegenerative diseases and BMAA studied in Guam where incidence is 50-100x higher, BMAA biomagnifies and is eaten by the Chamorro people in Southeast Asia.
- Cyanobacteria produces toxin, calculates in the cycad/cyano symbiosis, eaten by flying foxes (huge concentration), and then by the people.
Intercalary or terminal heterocyst
may be intercalary in filament or terminal
if intercalary, heterocysts are spaced at regular intervals
Monophyletic.
Descended from a common evolutionary ancestor (a single line of evolution) and are all related.
Diffuse growth in brown algae
- thallus growth
- new cells produced throughout the thallus (anywhere in body)
Describe this general feature of algae:
- Unicellular reproductive structures.
- In the rare cases where the structures are multicellular (they reproduce sexually), there is no distinction (or specialization) between fertile and sterile plants.
- exam
Define: Tinsel flagellum
Tinsel flagellum: Hairy flagella (like tinsel on xmas tree).
from other flashcards:
covered in tubular hairs (mastigonemes), used for motility and for capturing food
In algal morphology, a species can be palmelloid (also colonial); define this.
- Cells are all in one plane (flat plane) in a colony or coenobial, almost 2D.
Compare these 2 diatom types (centrics and pennates) based on the following characteristic:
- raphe present? motility?
- Centrics: No raphe (nonmotile when vegetative). Motile spermatozoids with single flagellum (not heterokont).
- Pennates: Raphe may be present (gliding motility by mucilage). No flagellated spermatozoids
Describe this type of projectile in the division chrysophyta (classes synurophyceae and chrysophyceae): Muciferous bodies
Contain granular mucilage bounded by single membrane
When discharged, contents form fibrous network outside the cell
If a chloroplast membrane has ___ membranes, what kind of endosymbiosis did it go through (primary or secondary)?
- 2 membranes:
- 2 or 4 membranes:
- 2 membranes: primary
- 2 or 4 membranes: secondary
In algal morphology, a species can be filamentous, more specifically, uniseriate; define this.
Has a single chain of cells.
Polyploid
multiple copies of each individual gene
Describe asexual reproduction in diatoms. Not mechanism, just the result and why this mechanism must be used.
- Size of vegetative cell is constrained by frustule (silica, can’t grow or stretch); cell can only grow by adding cingular plates and elongate in the girdle axis.
- Product of asexual reproduction are two dissimilar daughters where one is same size as parental epivalve and other is same size as parental hypovalve.
- Implication is that with successive generations, an increasing proportion of population is smaller than the original parent
pneumatocyst
- Also called air bladder or floats
- Like a beach ball, filled with air, holds the plant at the surface of the water
- An expanded area of thallus containing gases for buoyancy in phaeophyceae (brown algae)
Describe this feature of diatom frustule ornamentation: Striae.
- basic, the other words are on their own cards.
- Lines on surface of valve
- Little distinct rows of dots (at low magnification it looks like a line)
- Contains shallow depressions called areolae in which are smaller pores/slits called punctae.
- More heavily silicified ribs between rows of striae are costae
Describe this method of non-flagellar movement: Euglenoid movement.
What division has this?
- Exclusive to Euglenophyta
- Due to contraction and expansion of pellicular bands
- Cause unknown, may be associated with cytoplasmic streaming
alginate (which group?)
- sugar that retains or absorbs water and forms a viscous material
- thickeness varies between species
- outer, slimy, amorphous
- part of the cell wall in brown algae/ phaeophyceae; protects against desiccation, pounding waves, temperature changes, and salinity
- absorb 300X their weight in water (hygroscopic polysaccharide), used as a thickening agent in shampoo, cosmetics, food
Neurotoxins vs Hepatotoxins
Neurotoxins: affects muscles, functioning of the brain, effects on memory, communication, walking, outcome usually death
Hepatotoxins: affects the liver
List 4 new technologies that were developed post 1950’s that advanced our knowledge of algae.
- Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM).
- Electrophoresis.
- Chromatography.
- Radioisotopes.
Describe this ultrastructure (type of cell) in terms of DNA, nucleus, and organelles.
- Eukaryotes
Chromsomes (+ histones)
Nucleus and organelles present
Define (basic) this diatom frustule ornamentation in terms of:
- Araphidinate:
- Monoraphidinate:
- Araphidinate: no raphe on either valve
- Monoraphidinate: raphe on one valve
What is the usual range for algal life in terms of temperature and pH?
<0C to >40C, but up to 70C. Are alive below 0! Not just frozen.
pH <2 to >10.
Diatoms can be phytoplankton or benthic.
There are 2 subgroups of benthic diatoms, describe:
Epipelon.
- epipelon/epipelic: associated with mud/sediment.
- diurnal: changing over the course of the day
- algae migrate to the surface of the mud and water to be exposed to sunlight (increased photosynthesis)
- Move back into the mud at night to escape from predators by burrowing down into the mud (triggered by sunlight), more nutrients deeper in the ground as well.
Describe the cell covering of division chrysophyta (synurophyceae and chrysophyceae) in terms of:
- 2 types of scales (materials)
- What kind of symmetry would be found in each group.
- Chrysophyceae – radially arranged without clear pattern
- Synurophyceae – bilateral with multiple parts (dome, shield, bristles/spines), precisely arranged in pattern
Cyanobacteria can be halophiles, what does that mean?
salt loving
How do cyanobacteria store polysaccharides?
Store polysaccharides as cyanophycin granules or myxophycean starch (α-1,4 linked glucans do not react to iodine to give blue-black colour)
Parenchymatous
Mass of cells produced by division in three planes, forming solid axes, blades or complex thalli with specialized regions
Pigment
Molecule that absorbs light.
Estuary
where salt water and fresh water flow in together
Encystment vs Excystment
Encystment: to create a cyst or go into a cyst state
Excystment: coming out of a cyst
There are 4 major historical stages of phycology. Describe 4 of 4:
- Early 1950’s to present.
- Why did most of our algae knowledge come in the last ~70 years?
Much better microscopes and techniques used to study algae.
Terra-forming
to create a habitable environment (create life form on another planet)
Chromophyta can be thalloid, in the context of this division, what would that mean?
Thalloid – cells united in pseudoparenchymatous plate-like thallus
- exam
Describe each word in the pair as they pertain to the subject matter of this course, and explain the difference between them.
Sporophyte / Gametophyte
Both are part of the haplodiplontic lifecycle of algae.
A sporophyte is the diploid stage that produces spores from which the gametophyte arises.
The gametophyte is haploid and gamete producing.
*From notes exactly: Haplodiplontic (diplohaplontic): alternation of generations between gametophyte (gamete-producing generation) and sporophyte (spore-producing generation) stages.
Swarmers
haploid vegetative cells, motile that can form a new lorica and become a new radiating colony
Describe in general, the chloroplasts of diatoms in terms of:
- How many chloroplasts (and what structure) are present in centrics vs pennates?
- Centrics: large number of discoid chloroplasts
- Pennates: 1, 2 or 4 plate-like parietal chloroplasts
Describe in general, the chloroplasts of diatoms in terms of:
- How many membranes? What does this say about the endosymbiosis it underwent?
- Continuous or discontinuous ER?
- Surrounded by four membranes (secondary endosymbiosis)
- Chloroplast ER is continuous with outer membrane of nuclear envelope
Peripheral chloroplast
A chloroplast that goes around the cell
When did the first heterotrophic or chemosynthetic autotroph appear?
When did the first prokaryotic algae appear (cyanobacteria)?
When did the first eukaryotic algae appear?
- 3.5 billion ya.
- 2.7 billion ya.
- 1.5 billion ya.
Describe this modified plasma membrane (algal cell covering):
- Thecal plates.
- What division has it?
- Interior or exterior?
- Exclusive to Dinophyta (dinoflagellates)
- Vesicles below membrane contain unknown fibrillar compound (non-cellulosic) below which are microtubules
- Vary in size from nonexistent to thin to thick
- Internal, under cell membrane
Precipitation deficit vs Precipitation surplus
Precipitation deficit: less water coming down than coming back up into the atmosphere
Precipitation surplus: more water coming down than going back up into the atmosphere
Chromophyta can be unicellular, in the context of this division, what would that mean?
Unicellular – free-living with flagella
Gonidia is another name for ____.
Akinetes.
haplontic lifecycle
Predominantly haploid lifecycle (1 copy per gene) but has a short-lived diploid zygote stage.
Chloroplasts of Euglenophyta and Dinophyta have ____ membranes.
Chloroplasts of Euglenophyta and Dinophyta have three membranes.
Describe this modified plasma membrane (algal cell covering):
- Periplast.
- Interior or exterior?
- outside plasma membrane are granular fibrils, while inside are hexagonal or rectangular plates of protein interrupted by ejectosomes.
- Interior.
Define (basic) this diatom frustule ornamentation in terms of: Raphe
Can all diatoms have this?
- Longitudinal fissure in valve surface of pennates
- Slit that runs from one end of the frustule to the other
- May help diatoms in gliding motility
There are 2 theories of how eukaryotes formed.
Describe: The autogenous theory.
- Evidence?
Autogenous theory:
- “self-creating” (from pre-existing materials)
- Eukaryotes evolved through step-by-step changes in photosynthetic, respiratory and genetic units (slow and gradual)
- Gradual compartmentalizations and specialization of function
- Probably explains occurrence of nucleus, mitotic apparatus, and flagella
Phycology/Algology:
- What is the word derived from?
Derived from Greek phycos for seaweed (Latin fucus=seaweed).
Describe flagella in algae.
- Vegetative cells, composed of 9+2 microtubules (9 pairs of microtubules around a central core).
- Vary in number from 1 to >100 per cell.
- Most common in unicellular eukaryotes freely suspended in water have them, but may be present in some algal lifecycle stages only (zoospores).
What does NADS stand for?
North American Diatom Symposium
Chlorophyll (used to produce what, what colour of light it absorbs and reflects, do all algal groups have it?)
- Used to produce ATP and NADPH during photosynthesis
- Can only absorb blue and red light, so appear green
- All algal groups have two at most, always Chlorophyll a, then either b, c, d, or f
Intercalary vs terminal heterocyst
may be intercalary in filament or terminal
if intercalary, heterocysts are spaced at regular intervals
Compare these 2 diatom types (centrics and pennates) based on the following characteristic:
- differences from normal type of reproduction (asexual and sexual), and are they oogamous or isogamous?
- Centrics: Form resting cells (or cysts). Oogamous sexual reproduction (large, nonmotile egg and smaller, motile sperm).
- Pennates: No flagellated spermatozoids. Sexual reproduction by isogamy (conjugation, 2 similar gametes)
Compare these 2 classes (synurophyceae and chrysophyceae) in division chromophyta in terms of….
- Chlorophyll C2 present (yes or no)
- Synurophyceae: no
- Chrysophyceae: yes
Describe differences occurring in mitosis in mesokaryotes.
- No interphase (continuous DNA synthesis)
- Nuclear membrane persists during mitosis
- No microtubules laid down during nuclear division)
Algae can store glucose as a high molecular weight compound. There are 3 types of a-1,4 linked glucans, describe: True starch.
- What does it contain
- How it would stain with iodine
- Where it would be found (algal type and location)
- Contains amylose and amylopectin.
- Stains purple with iodine.
- Found in Chlorophyta (only algal group where starch stored inside chloroplast rather than cytoplasm).
Algae can store glucose as a high molecular weight compound. There are 3 types of B-1,3 linked glucans, describe: Laminarin.
- What form is it, and where is it stored?
- What 2 algal groups would have it?
Oil-like liquid stored in vesicle around pyrenoid.
Found in phaeophyta and chromophyta.
What is phenetic classification?
Use of physical appearances, morphological, biochemical, and physiological features to classify into different groups .
Define: Symbiont
two organisms in close association with each other
Chromophyta can be colonial, in the context of this division, what would that mean? (how are they linked)?
Colonial – number of flagellates linked
Uniseriate vs Multiseriate
Filamentous (thread-like) usually composed of single rows of cells (uniseriate) and sometimes several rows (multiseriate)
Define (basic) this diatom frustule ornamentation in terms of:
- Biraphidinate:
- Pseudoraphidinate:
- Biraphidinate: raphe on both valves
- Pseudoraphidinate: clear area in centre of valve without fissure
Define: Heterocyst in terms of…
- Their function.
- When more would be produced.
- Do they use oxygen?
- Thought to function in nitrogen fixation; the further away from the heterocyst, the lower the nitrogen concentration; distance between heterocysts indicates the concentration of nitrogen in the environment; product diffuses to neighbouring cells, with less going to cells farther away.
- Produced in low nitrogen environments (number indicates how low nitrogen the environment is).
- They are anoxegenic (since nitrogen fixation is negatively affected by oxygen, it creates an anaerobic zone).
Are heterocysts a prerequisite for nitrogen fixation?
Heterocysts are NOT a prerequisite for nitrogen fixation
First photosynthetic organisms with two photosystems producing oxygen as product (first oxygenic autotroph) = ______.
Cyanophyta
List 5 socio-economic effects or uses for diatoms.
1. Toxins 2, Symbioses 3. Environmental indicators 4. Industrial applications 5. Forensic investigation
phagotrophy (super basic)
ingestion of solid particles
Beta-methylamino-L-alanine (BMAA) is produced by what algal phyla?
cyanophyta
Algae are distributed in virtually every environment on earth. In terms of aerial/terrestrial environments, define this possible habitat:
- Symbioses.
Live with something else, like lichens = fungi + algae
Algae are distributed in virtually every environment on earth. In terms of aquatic environments, define this possible habitat:
- metaphyton.
metaphyton = between plant —> formally attached
Starts living on a plant (epiphytic) but becomes so numerous that it detaches and falls off, then called metaphytic.
“elephant snot”
Chromophyta can be coccoid, in the context of this division, what would that mean?
Coccoid – spherical or elliptical, non-motile cells surrounded by walls, sometimes in colonies
Lamellae
Thylakoids grouped in three, in chloroplasts.
- Diatoms have this
Compare these 2 classes (synurophyceae and chrysophyceae) in division chromophyta in terms of….
- Symmetry/patterning of scales
- Synurophyceae: Bilateral symmetry with pattern
- Chrysophyceae: Radial symmetry with no pattern
What is mucilage made of?
A gelatinous material produced by algae and composed of water, polysaccharides, and protein.
Are diatoms motile yes or no?
no, no flagella
Describe cysts as diatom reproduction.
- Formed within vegetative cells (usually marine centrics)
- Thick-walled, maybe spherical, dissimilar to vegetative cell
- Under appropriate environmental conditions, cyst enlarges and develops two valves larger in size than parental ones
- Another means of restoring population size
Prokaryotes have ___ thylakoids in cytoplasm.
free
Algae are distributed in virtually every environment on earth. In terms of aerial/terrestrial environments, define this possible habitat:
- Epilithon.
On rock surfaces.
Define: Zoospore (planospore).
A motile stage of asexual reproduction.
Pigmentation in chromophyta (diatoms): 3/4 main.
Chlorophylls A, C, Carotenoids (very abundant, particularly fucoxanthin, which masks green colour of chlorophylls)
Algae are distributed in virtually every environment on earth. In terms of aquatic environments, define this possible habitat:
- periphyton.
attached to any surface (animal, rock, plant)
Define: Biomagnification (and an algal toxin that biomagnifies).
As it goes up a food chain, the higher the concentration of the toxins gets in each stage.
Define:
- Punctae (Punctum=singular)
- Areolae (areolum=singular)
- Diatom frustule components, specifically, part of striae.
- The striae contains shallow depressions called areolae in which are smaller pores/slits called punctae.
Define: Heterocyst in terms of…
- Where might one be found?
- How does it differ in appearance from vegetative cells (what about if they’re intercalary)?
- Found only in some filamentous Cyanophyta
- Differ in appearance from vegetative cells:
- Larger and thicker cell wall
- Refractive polar nodules at connections with vegetative cells
- Cell contents homogenous and yellow in colour
- May be intercalary in filament where they are spaced at regular intervals or terminal; if intercalary, heterocysts are spaced at regular interval.
Haplontic vs Haplodiplontic vs Diplontic (algal lifecycles)
Haplontic: predominantly haploid stage
Haplodiplontic (diplohaplontic): alternation of generations between gametophyte (gamete-producing generation) and sporophyte (spore-producing generation) stages
Diplomatic: predominantly diploid stage
List 5 ways that cyanophyta reproduce asexually. Can they reproduce sexually?
- Binary fission.
- Trichome fragmentation.
- Germination from akinetes.
- Germination from hormogonia.
- Endospores and exospore.
- no evidence of sexual reproduction.
Define: Thylakoids.
Flattened membrane bound sack where pigments occur for photosynthesis.
where most brown algae live
Vast majority are marine
and other substrata in inter freshwater species (4 genera)
and live attached to rocks and other substrate in the tidal zone; which is shallow/near shore so they can get enough light. Not so much in the open ocean, but can be in kelp forests which are a bit farther from shore.
What kind of lifecycle do diatoms have?
Diplontic, but gametes are haploid
Able to switch between auto and heterotrophy
mixotrophy
Algae are distributed in virtually every environment on earth. In terms of aquatic environments, define this possible habitat:
- neuston.
live on the air-water interface (like right on surface crust of water)
Mixotrophy
- can switch accordingly back and forth between autotrophy and heterotrophy.
- lots of light = photosynthetic
- no sun = heterotrophic.
- Grow faster when they’re autotrophic.
Some suggest phylogenetic affinities based on photosynthetic pigments.
Describe the phycobilin series in terms of:
- What 2 similarities are present between the members of the group (Cyanophyta, Rhodophyta, Cryptophyta)?
- Red algal chloroplasts resemblemble cyanobacteria with pigments associated with a single membrane.
- No motile stages in lifecycles
what’s Prochloron (Prochlorophyta) and what is the significance?
- discovered 1975 by Ralph Lewin (*loves him but maybe not critical)
- Thought by many to be an intermediate form between prokaryotes and eukaryotes:
- Prokaryotic
- No phycobilins
- Chlorophyll B in addition to chlorophyll A
- Thylakoids stacked in pairs, not monolayers
most common morphology and flagella in: chrysophyceae
Unicellular or colonial
Two unequal flagella
If the classification name of an algae ends with _____, which hierarchical level is it?
- phyta
Division.
Describe this method of asexual reproduction in algae.
- cell division or binary fission.
- Simple cell division (most primitive.
To summarize Lee’s classification, there are 4 main algal groups.
- Eukaryotes with 2 chloroplast membrane:
- 3 divisions.
Divisions Glaucophyta, Rhodophyta, Chlorophyta.
Brown Tides + which group causes them
*skipped slide so not priority
-Aureococcus (chrysophyta) causes “brown tides” in coastal waters where causes decline in sea grass (due to shading) and scallops (interference with filter-feeding)
What is numerical aperture?
The ability to see two discrete objects (with poor N.A. you will only see one object).
List 4 new technologies that were developed post 1950’s that advanced our knowledge of algae.
- Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM).
- Electrophoresis.
- Chromatography.
- Radioisotopes and stable isotopes.
in the sexual reproductive cycle of dinobryon (chrysophyte), are they monoecious or dioecious? iso, aniso, or oogamous?
- Dioecious (Male and female)
- Anisogamous
4 types of meristems (phaeophyceae)
- Apical=at ends/tips of branches
- Intercalary=within branches; may be transitional between fronds and stipe
- Trichothallic=at base of terminal hair (filament)
- Meristodermal=region located on thallus surface (increases girth)
In algal morphology, a species can be filamentous, and may be “true or false”; define this.
True branching is when the alga grows in a new plane (second plane).
False branching is when serrate algal may get stuck together and appear branched but aren’t (ie. caught together by a common coat of muscilage).
Describe this accessory pigment: Phycobilins
- Colours (name of them)
- The 3 phyla they’re exclusively found in
- Red or blue-green.
- Phycoerythrin (red).
- Phycocyanin (blue-green).
- Pigments found exclusively in Cyanophyta, Cryptophyta, and Rhodophyta
List the 4 general features of algae.
- No differentiation of parts.
- Vegetative reproduction is common.
- Unicellular reproductive structures.
- Zygote germination (if sexual).
Define: Chromatic adaption.
Algae modify pigment content for environment.
Define: Extremophile
Organisms that love extreme conditions
Chromophyta can be amoeboid, in the context of this division, what would that mean?
Amoeboid – naked cells with pseudopodia
Dianoflagellates have long spines, what is the most likely use for them?
- To increase surface area and to allow them to float better/sink less - spines are rarely for protection.
When did the first eukaryotic algae appear?
- 1.5 billion ya.
Of the 5 eukaryotic supergroups, 3 of them contain algae. List the names of these supergroups.
- Excavates
- Chromalveolates
- Plantae
Describe the diatom frustule structure in terms of:
- Cingulum/cingular bands/girdle
- separates the epivalve and hypovalve of the frustule in Diatoms
____ is a specialized cell produced by some cyanobacteria that is thought to be the site of nitrogen fixation.
heterocyst
Describe this algal flagella type:
- Isokontous.
Isokontous: Flagella (more than 1) that are similar in length and type.
Tinsel vs Whiplash Flagellum (ex. in chrysophytes)
- Tinsel flagellum: covered in tubular hairs (mastigonemes), used for motility and for capturing food
- Whiplash flagellum: very fine hairs or none at all, usually shorter and sometimes serves no role in motility but more for helping tinsel flagellum to bring food closer to the cell for phagocytosis, has swelling at base which contains photoreceptor (electron dense area), eyespot (near chloroplast) and flagellar swelling interact in response to light direction (phototaxis)
○ Both flagella with typical 9+2 microtubular anatomy
Chlorophyl absorbs light in the range of __nm (___) to ___ nm (___).
* number and colour
400 (blue) to 700 (red).
Statospores (sometimes called Cysts) in chrysophytes.
- formation is included but not necessary for this card, just to review it.
- Can be formed sexually or asexually
- Siliciceous-walled (silica) sphere into which cytoplasm contents flow, plugged with unsilicified material (polysaccharide)
- Usually formed inside vegetative cells, inside the plasma membrane (***frustule formed outside the cell)
- Germinate when conditions improve, plug dissolves, protoplast emerges and forms flagella as it moves out
- A resistant stage, shuts down until environment is more favourable
○ Formation:
- At early stage it is a thin membrane
- As it progresses, it gets thicker and thicker
- A hole gets filled and forms a protein plug
- The contents outside the statospore is discarded
- New membrane is formed inside the statospore
- Don’t break down in lake sediments and, due to ornate pattern on external surface, are diagnostic features for species that produced them
Compare these 2 classes (synurophyceae and chrysophyceae) in division chromophyta in terms of….
- Eyespot present (yes or no)
- Synurophyceae: no
- Chrysophyceae: yes
Despite morphological and biochemical differences, it is thought eukaryotic algae are descended from _____ ______.
Despite morphological and biochemical differences, it is thought eukaryotic algae are descended from autotrophic prokaryotes.
“Phyta” vs “Phycos”.
Phyta - plant.
Phycos - algae.
To summarize Lee’s classification, there are 4 main algal groups.
- Prokaryotes:
- 1 division (includes ____).
Division Cyanophyta (includes Prochlorophyta).
Cyanobacteria are highly adaptable and can live in soil. What are some of their roles in soils (including any things they contribute to soil (2), how their mucilage affects it, and crusts).
- N-fixers are potential source of soil nitrogen
- Provide initial organic matter in primitive soils, may be first to colonize after something happens
- Mucilages bind soil, reducing erosion
- Crusts help to retain moisture (looks like a brain, they’re adapted for drier environments)
In algal morphology, a unicellular species can be coccoid, what does this mean?
A spherical cell, the same shape all around.
If you see these features, how can you know which class of division chrysophyta it is?
- Contractile vacuole (water pump) on same side of cell as flagella
- Flagella are perpendicular (heterodynamic)
- Heterokont (2 dissimilar flagella) = whiplash and tinsel
- Granules at base of flagella
- Eye spot
- Contractile vacuole (water pump) on same side of cell as flagella = chrysophyte (NOT synurid)
- Flagella are perpendicular (heterodynamic)
- Heterokont (2 dissimilar flagella) = whiplash and tinsel
- Granules at base of flagella
- Eye spot in chyrsophyta (not in synurid)
Scale symmetry of Chrysophyceae
- Chrysophyceae – radially arranged without clear pattern
Describe this modified plasma membrane (algal cell covering):
- Cell wall.
- Can they be incomplete? What is this called?
-Usually complete but may be incomplete, such as lorica in some Chrysophyta and Euglenophyta
Seven Pillars of the BMAA-ALS Hypothesis
- Cyanobacteria produce BMAA
- BMAA exposure is ubiquitous
- BMAA can be inserted into proteins
- BMAA can be biomagnified within ecosystem
- BMAA is neurotoxic to motor neurons
- Individuals vary in vulnerability to BMAA
- BMAA occurs in brain tissue of ALS and Alzheimer’s disease patients but not health controls
Physodes (+which group)
- Vesicles in cytoplasm of phaeophyta associated with chloroplast
- Contain colourless, highly refractive polyphenolic compounds such as tannins
- Are colourless, highly absorptive of the UV light to protect the cell, the algae live in shallow water where ultra-violet light is more abundant at the surface compared to going deeper in the water
What kind of xenogenous development did euglenophyta have?
incorporated chlorophyl from eukaryotic green algae (ingested it as food)
Which 3 algal groups have chlorophyll B, in addition to A?
Prochlorophyta, Chlorophyta, Euglenophyta
Meristematic and Meristem
new cells produced in specialized area called meristem (cells that are rapidly dividing)
Describe this ultrastructure (type of cell) in terms of DNA, nucleus, and organelles.
- Prokaryotes
Coiled DNA (no chromosomes)
No nucleus
No organelles
Describe this algal morphology: Unicellular.
Just a single cell.
Define: Vacuole (function, where it’s found).
- An organelle that functions in storage of waste and nutrients.
- Found in eukaryotic algae.
How do diatoms get their nutrition? 3 main types.
- Most are photolithotrophic and store photosynthate in the form of fats, oils, and
chrysolaminarin, BUT very hard to grow in lab, indicating that they’re most likely auxotrophic – require one or more organic nutrient (e.g., vitamins) that they can’t make themselves. - Some are mixotrophic (facultatively heterotrophic), can switch between autotrophy or heterotrophy.
- A few are obligately heterotrophic (colourless).
Toxins vs Toxicants
Toxins: something that is of biological origin (snake venom)
Toxicant: something that is toxic not of biological order (pesticides), very inclusive or anything harmful to organisms, includes toxins, includes human made things
Pheromones
Gametes coming together is stimulated by pheromones (chemical that stimulates reproduction); erogen released by female to attract the male
What 3 algal divisions may have naked plasma membranes (no cell covering)? Are there situations where other ones may have this?
- Found in some members of Chromophyta, Chlorophyta, -
and Rhodophyta.
- Some reproductive stages may have naked membranes
Trichome vs filament.
Trichome: linear chain of cells, that are not surrounded by a mucilage coat.
Filament: a linear chain of cells surrounded by a mucilage.
*trichome + mucilage sheath = filament
In what ways are cyanobacteria similar to plants? 3 main reasons.
Chlorophyll A is primary photosynthetic pigment (no bacteriochlorophyll or chl B)
Have phycobilins (phycoerythrin and phycocyanin) like Cryptophyta and Rhodophyta
Oxygenic photosynthesis
Holdfast
- Parts of the plants that resemble roots but not true roots, can wrap around rocks ad other plants, anchors the plant
- Is the modified basal region for substratum attachment in phaeophyceae (brown algae)
Describe this method of non-flagellar movement: mucilage secretion.
What divisions have this?
- Slime trail
- Found in Bacillariophyceae (diatoms) and desmids
- Mucilage may be secreted from frustular pores (in diatoms)
Some suggest phylogenetic affinities based on photosynthetic pigments.
Describe the non-masked series in terms of:
- Which 3 groups are part of it?
-Chlorophyta, Euglenophyta, Xanthophyta
Algae are distributed in virtually every environment on earth. In terms of aerial/terrestrial environments, define this possible habitat:
- Sympagic.
Inside ice (not frozen, living and photosynthesizing). Word means “with ice”.
What are binomial systems for naming?
Genus + specific epithet, a naming system used for algae.
Is algae classification monophyletic? If not, how is it classified?
No, algae classification is phenetic.
Describe this of nutrition in chrysophyta (classes synurophyceae and chrysophyceae): Phagotrophy
- What they eat, mechanism, how much/how fast they can eat.
Ingestion of solid food particles such as bacteria, yeast, small eukaryotes into food vacuole of pigmented or non- pigmented chrysophytes and synurids
Some taxa obligately phagotrophic (e.g., Ochromonas spumella)
Mechanism:
- Particle seized by tinsel flagellum and taken in as a food vacuole.
- Ingestion complete within 2-3 seconds of contact and up to 3 bacterial cells ingested per 5 minutes
Describe this method of non-flagellar movement: Gliding.
What division has this?
- Slow, gliding motion
- No visible organ responsible
- May be due to regularly arranged fibrillar extensions of the protoplasm
- Found in Cyanophyta
Describe chloroplasts in division chrysophyta (classes synurophyceae and chrysophyceae) in terms of:
- how many thylakoids per stack (and what is this called)?
- are pyrenoids common or no?
Thylakoids stacked in threes (lamellae)
Pyrenoids common in chloroplast
What’s diatomite and what are some uses for it?
- Diatomaceous earth (diatomite), produced by diatoms.
- Mined from deep deposits of mostly marine origin
- Diverse commercial uses:
Abrasives (polishes, toothpaste)
Filtration
Absorbents (cat litter) Insecticides
Brewing alcohol
Whorls of branches
branches coming off one point and radiating into all directions
Describe this general feature of algae:
- Zygote germination (if sexual).
- Does not occur in situ; gametes may be retained on the vegetative thallus, but ultimately, the zygote germinates in the environment.
Describe this ultrastructure (type of cell) in terms of DNA (size, modifications), nucleus, and organelles.
- Mesokaryotes
Chromosomes are very large (no histones)
Organelles and nucleus present
Describe this modified plasma membrane (algal cell covering):
- Scales.
- What 2 divisions have it?
- Interior or exterior?
- What is their function?
- inorganic silica pieces or plates which covers the cell, as well as organic material like carbohydrates
- Mostly in Chrysophyta
- Function in protection and, by increasing surface area, aid in buoyancy
Algae are distributed in virtually every environment on earth. In terms of aerial/terrestrial environments, define this possible habitat:
- Edaphic.
In soil.
in the sexual reproductive cycle of synura (chrysophyte/synurids), are they monoecious or dioecious? iso, aniso, or oogamous?
can this cycle occur asexually too?
- how do the males find the females? What happens when they do?
- Dioecious.
- Anisogamous.
- Sexual ONLY. Meiosis and statospore encystment to produce new gametes.
- Female is non migratory, male contacts female colony.
- Gametes combine to a binucleate organism (2 nuclei, 2 vesicles, 4 chloroplasts, then becomes statospore).
Algae can store glucose as a high molecular weight compound. There are 3 types of a-1,4 linked glucans, describe: Floridean starch.
- What it’s similar to in plants
- Where it would be found (algal type)
- Chemically similar to amylopectin of higher plants.
- Found in Rhodophyta
Cyanobacteria can have specialized cells called hormogonia. What are they?
(hormogonium=singular)
Filament fragment detaches (is motile) and can form end to end with a new filament, formed during asexual reproduction in Cyanophyta
Which algal group has chlorophyll F, in addition to A?
Cyanobacteria (maybe)
What is the point of sexual reproduction in algae?
**Function of sex in algae does not occur for genetic diversity BUT for surviving adverse conditions or environment
- Another means of restoring population size in marine centric diatoms after becoming too small from cell division (asexual reproduction)
- Genetic recombination/diversity
- Surviving adverse conditions (auxospore - A means to escape adversity of the environment)
Stalk / Stipe
Stem-like region of thallus in phaeophyceae (brown algae)
Cortex location in phaeophyceae
around the medulla, has pigments and photosynthetic cells
Algae can store glucose as a high molecular weight compound. There are 3 types of a-1,4 linked glucans, list them.
- True starch.
- Cyanophycean (myxophycean) starch.
- Floridean starch.
Photolithotrophy
Uses light energy to make it’s own food.
Unicellular vs Coccoid Morphology
Unicellular: Free-living with flagella, motile
Coccoid : Spherical or elliptical, non-motile (*difference with unicellular) cells surrounded by walls, sometimes in colonies
Describe this type of sexual reproduction in algae:
- Oogamous
Oogamous: One small motile male gamete (sperm) and one non-motile gamete (egg) = zygote, most advanced form.
In algal morphology, a unicellular species can be flagellate or aflagellate, what does this mean?
The presence of absence of a flagella.
How do diatoms accomplish movement/motility?
- No flagella.
- Motility exclusive in pennates with a raphe, or some centrics with labiate processes (excrete mucilage, can move up to 25um/sec).
- Requires surface so not possible in planktonic diatoms (or araphidinate pennates)
When did the first prokaryotic algae appear (cyanobacteria)?
- 2.7 billion ya.
Describe: Electrophoresis.
- Used to separate nucleic acids (DNA and RNA) through viscous gel where electric field causes negatively charged nucleic acids to migrate to positive anode.
- Allows for taxonomy based on DNA/RNA (genetics) instead of morphology.
- Used in population genetics.
Algae can store glucose as a high molecular weight compound. There are 3 types of B-1,3 linked glucans, describe: Chrysolaminarin.
- How does it differ from laminarin?
- What algal group would have it?
- Higher glucose content (higher # of glucose).
- Found in Chromophyta.
Contribution of Lynn Margulis, Dr. G’s hero! In terms of where she said things came from.
- Nucleus from ancient Archaea methanogen
- Mitochrondrion from bacterium inside another
- Chloroplast from cyanobacterium inside colorless bacterium
Where are chyrsophytes and synurids most commonly found (division chromophyta)?
- Maximum diversity in temperate climates
- Typically in chemically-dilute freshwater, sometimes brackish or marine (like Canadian Shield)
Autogenous Theory vs Xenogenous Theory
Autogenous theory:
- “self-creating”
- Eukaryotes evolved through step-by-step changes in photosynthetic, respiratory and genetic units (slow and gradual)
- Gradual compartmentalizations and specialization of function
- Probably explains occurrence of nucleus, mitotic apparatus, and flagella
Xenogenous theory:
- Prokaryotes obtained organelles via series of endosymbioses (cells eat other cells) with other prokaryotes
- Mitochondrion and chloroplast have their own extranuclear DNA, and divide autonomously from nucleus via binary fission (like Bactria)
- Glaucophyta contain endosymbiotic cyanobacteria (cyanelles) that perform chloroplast function
- Some dinoflagellates also contain endosymbiotic cyanobacteria (phaeosomes)
Where are chyrsophytes most often found?
- Mostly freshwater, but few in brackish or marine
- Many phytoplanktonic in oligotrophic (low phosphorus) lakes where they can be important component of food web
- Some form “deep peaks” (metalimnetic blooms)
- Non-motile members in cold, fast-moving streams and shallow ponds
- Acid habitats, such as peat bogs, support large variety of motile, epiphytic, and endophytic taxa
Describe: Stigma/Eye spot
-Many flagellated cells have swelling close to base of one flagellum.
2 parts:
- Paraflagellar body or photoreceptor. Usually aligned with an eyespot and functions in determining direction of movement that results from flagellar motion.
- Pigments that can sense light.
Algae can store glucose as a high molecular weight compound. There are 3 types of a-1,4 linked glucans, describe: Cyanophycean (myxophycean) starch.
- What it’s similar to in animals and fungi
- Where it would be found (algal type)
- Similar to glycogen found in animals and fungi.
- Found in Cyanophyta
meristoderm in phaeophyceae
on the exterior of the stipe, like epidermis, it’s meristematic and increases diameter of the stem
How can diatom mucilage be used to extend their reach? What is a term for this?
- Allow for distance away from the plant, rock or animal by having a stalk/peduncle (very long compared to the frustule, like a lollipop), gives advantage to get to water with more nutrients, more light.
To summarize Lee’s classification, there are 4 main algal groups.
Eukaryotes with chloroplasts surrounded by 2
membranes of chloroplast ER:
- 3 divisions.
Divisions Cryptophyta, Chromophyta, Prymesiophyta.
Compare these 2 diatom types (centrics and pennates) based on the following characteristic:
- Frustrule morphology (symmetry)
- Centrics: Radial or trilateral (gonioid) frustular morphology
- Pennates: Bilateral or trellisoid frustular morphology
Describe this method of asexual reproduction in algae.
- Cysts
What they can form from, and what the usual purpose is.
- Common in many algae.
- Form from zygote (sexual) or vegetative (asexual cell)
- Usually as a means of surviving adverse conditions.
- exam
Define: Pseudoraphe
Pseudoraphe: clear area in centre of valve without fissure.
Looks like a raphe, but doesn’t go all the way through.
Some suggest phylogenetic affinities based on photosynthetic pigments.
Describe the non-masked series in terms of:
- What 2 similarities are present between the members of the group (Chlorophyta, Euglenophyta, Xanthophyta)?
- Photosynthetic pigments not masked by accessory pigments
- Green produced by chloroplasts
Describe this of nutrition in chrysophyta (classes synurophyceae and chrysophyceae): Mixotrophy
- What is ingested?
- mixotrophy = ability to switch from auto/heterotrophy
Dinobryon can derive 50% of its carbon from phagotrophic ingestion of microorganisms, competing effectively with crustaceans, rotifers, and ciliates
Describe this method of asexual reproduction in algae.
- fragmentation
- Fragmentation (seldom organized) – akinetes (break off cyanophyte filament)
Define: silica lemma
- In diatoms.
- Where silica deposition begins (in the middle).
- good exam question *
In cyanophyta, all groups except Chamaesiphonales have gas vacuoles (pseudovacuoles).
Describe what they are.
Self-erecting cylindrical vesicles (in bundles) containing atmospheric gases that gives buoyancy.
Filling with air lets them float to the surface but increases cell turgor pressure (due to more light = more photosynthates/ sugars produced = higher osmotic pressure), causes the vacuoles to break, the cyanobacteria then sinks to darker waters and uses up the sugars, osmotic pressure is released and more gas vacuoles are made, and then it floats up again.
Define: Akinete.
- An enlarged, differently shaped, granular structure (modified vegetative cell).
- “Resting spore”, unique to cyanophyta.
- Functions as storage for products of photosynthesis.
- Also an asexual reproductive structure, it drops off the organism and can overwinter, then repopulate the colony after.
- Also called a gonidia
Tannins (+which group), and what are the functions?
- held in physodes (vesicles) in phaeophyceae
- readily oxidized in air, resulting in formation of brown or black pigment, phycophaein, giving many dried brown algae a characteristic black colour
- Absorb UV light and protect the thallus from UV light damage
- Inhibit growth of epiphytes (something growing on a plant, which can shade the brown algae)
- Discourage herbivores due to astringency
- Play a role in fertilization by blocking polyspermy (more than one sperm unites with the egg)
Plasmodesmata
in brown algae, adjacent cells share common end wall which enable intercellular connection, most obvious in trumpet cells of medulla in kelp stripes.
-Resemble sieve plates in vascular plants
Describe this type of sexual reproduction in algae:
- Isogamous
Isogamous: morphologically similar gametes, + and -, most primitive form.
How are cyanobacteria symbionts (5)?
- Lichens (a fungus and alga association): 8% of lichens have cyanobacterial partners, usually a nitrogen fixing taxa.
- Diatoms in low nitrogen environments (cyano’s inside them)
- Sponges
- Ferns
- Glaucophyta
Paralytic Shellfish Poisoning (PSP)
- Who produces this?
- What is the effect in the body (not side effects)?
- Antidode?
- Toxin domoic acid produced by marine diatom Pseudonitzschia pungens
- Toxin accumulates in flesh of filter-feeding animals such as mussels, clams
- Domoic acid is excitatory amino acid (similar to glutamate) that binds to glutamate receptors irreversibly, causing nerve cells to continuously transmit impulses until they die.
- No antidote and no way to remove toxin from tainted food
Nutrient Requirements to grow diatoms
C. Hopkins Café. Mighty good but not always clean. Comin’ cousin Moe? Si!
CHOPKNS CaFe Mg B NaCl CuMn CoZn Mo Si *macronutrients listed first and micronutrients
What is the Macdonald-Pfitzer Rule
- When diatom daughter is about 1/3 of original parental size, they become incapable of further size reduction and must undergo size regeneration (the threshold, stimulates sexual reproduction).
- Sexual reproduction or cyst formation can restore full parental size.
Obligative vs Facultative
Facultative: you can switch from autotrophs to heterotroph depending on environment.
Obligative: no choice on which method of acquiring nutrition.
What kind of xenogenous development did chlorophyta have?
incorporation of prochloron like green prokaryote
Define: Isomorphic or anisomorphic (and what lifecycle has this).
- Isomorphic or anisomorphic = alternation of generations (2N or N).
- In haplodiplontic lifecycle.
Describe chloroplasts in division chrysophyta (classes synurophyceae and chrysophyceae) in terms of:
- number of membranes
- how chloroplasts are connected to nucleus
Four membranes (two chloroplast membranes and two members of chloroplast ER)
Connected to nucleus by fold of chloroplast ER continuous with the nuclear envelope
Define: sporangium.
A spore producing cell.
2 names for the study of algae.
Phycology or Algology.
How are glaucophyta and cyanophyta symbionts? Not in detail, just how.
- Glaucophyta are small eukaryotes with non-pigmented cells with endosymbiotic cyanobacteria, called cyanelles (extra membrane).
Describe this accessory pigment: Carotenoids
- Colours
- Function
- Examples (4)
- Brown, yellow, orange, red
- Increases useful range of absorbed light, and protect photo centres from excessive light
- ex) Beta-Carotene, Fucoxanthin, Peridinin, Siphonoxanthin
- good exam question *
Isogamous vs Anisogamous vs Oogamous (sexual reproduction)
Isogamous: morphologically similar gametes, + and -, most primitive form.
Anisogamous: Morphologically dissimilar.
Oogamous: One small motile male gamete (sperm) and one non-motile gamete (egg) = zygote, most advanced form.
Which 4 algal groups have chlorophyll C, in addition to A?
Chromophyta, Cryptophyta, Haptophyta, Dinophyta
Cyanobacteria are one of the most common algae in lakes and streams, occupying such habitats as plocon (_______), epiphyton (_____), plankton (_____).
Cyanobacteria are one of the most common algae in lakes and streams, occupying such habitats as plocon (sediment crusts), epiphyton (on plants), plankton (free-floating).
Pyrenoids
- A sub cellular compartment inside chloroplasts where photosynthesis is taking place and carbon for photosynthesis is stored (turn blue black when iodine applied due to concentration of starch in pyrenoids)
- Diatoms have this
allochthonous vs autochthonous
allochthonous (originating outside the lake basin) and autochthonous (originating within the basin)
Endospores vs Exospores
-both produced during asexual reproduction
Endospores: produced inside of the parent cell
Exospores: produced externally from parent cell
cell covering in: synurophyceae
Cell membranes decorated with siliceous scales and bristles
When did the first heterotrophic or chemosynthetic autotroph appear?
- 3.5 billion ya.
Compare these 2 classes (synurophyceae and chrysophyceae) in division chromophyta in terms of….
- Contractile vacuole position relative to flagella
- Synurophyceae: Posterior, opposite flagella
- Chrysophyceae: Anterior, by flagella
Dioecious
- Oikia or Oikos = home
- Dioecious = “oecious” comes from “oikia”
- Two places in the reproductive structure, two strains (male and female or male and female) or two houses
Frustular morphology is basis for diatom classification, describe this symmetry:
- Centric
- Gonioid
- Pennate
Centric (radial or isodiametric) Gonioid (trilateral)
Pennate (bilateral
- Centric: radial or isodiametric.
- Gonioid: trilateral, triangular symmetry.
- Pennate: bilateral, symmetry on one axis or two.
First algae to evolve on Earth = ____.
Cyanophyta
chloroplast membrane numbers in phaeophyceae (and chromophytes including diatoms, chysophyyes, synurids)
Chloroplasts: four membranes, thylakoids in stacks of three (lamellae)
Describe the declining relative growth phase in growth in terms of 3 limitations.
Is this before or after stationary phase?
- nutrient limitation
- self shading (ligt limitation)
- auto-inhibition (accumulation of toxic wastes)
before stationary phase
Endocytosis vs Phagocytosis
Endocytosis: bringing something into the cell (any material, engulfed)
Phagocytosis: bringing particles into the cell (occurs through endocytosis, a solid particle is brought into the cell by an infolding of the cell membrane as a vesicle)
** he didn’t give the details in brackets
In algal morphology, a species can be filamentous, more specifically, multiseriate; define this.
Has multiple chains of cells (biseriate = 2, triseriate = 3, etc).
Describe this method of non-flagellar movement: Ejectosomes.
What division has this?
- Exclusive to Cryptophyta
- Discharged from cell body when irritated, propelling cell in opposite direction
Gonidia vs hormogonia
- Gonidia/akinete: Enlarged vegetative cell (stores carbohydrates) and becomes an asexually reproductive structure (drops off the organism and repopulates colony).
- Hormogonia: Filament fragment detaches (is motile) and can form end to end with a new filament, formed during asexual reproduction.
** both present in cyanophyta
In algal morphology, a species can be colonial; define this.
More than 1 cell.
Glaucophyta are symbionts with cyanophyta, describe cyanelles.
- Glaucophyta are small eukaryotes with non-pigmented cells with endosymbiotic cyanobacteria, called cyanelles (extra membrane).
- Like cyanobacteria, cyanelles have unstacked thylakoids and contain chlorophyll A, phycobilins, own DNA (5-10% of free-living cyanobacteria, probably due to gene transfer) – but they cannot live independently and have no respiratory electron transport.
- NOT a chloroplast
Contribution of Lynn Margulis, Dr. G’s hero! But NOT where she said things came from.
- wrote paper “The origin of mitosing eukaryotic cells” built on work of 19th and 20th century scientists (advanced the xenogenous theory)
- First to rely on direct microbiological observations
- stuck to endosymbiosis theory
- Science discoveries not taken seriously, maybe due to being a woman
Describe this modified plasma membrane (algal cell covering):
- Cell wall.
- What ingredients are they made out of?
- Most abundant ingredient: cellulose but may be replaced by mannan or xylan in some Chlorophyta
- May be calcified, Charophyta has calcium carbonate on the exterior
Muscilage
- Cyanophyta cell wall can be embedded in mucilage sheath, Diatoms in mucilage tubes or sheets
- Creates a filament, glues things together
- Diatoms use to escape from salt water, make slime trails ; Centric (do not produce slime) and Pennate (produce slime)
- used in our cosmetics to add texture by alginate
Define: Heterocyst.
Found only in some filamentous Cyanophyta
Modified vegetative cells (larger and thicker walls, contents yellow and homogenous, polar nodules)
- PS1 only (anaerobic) to allow nitrogenase to reduce N2 to ammonia (NH3).
- Number of heterocysts negatively correlated with N concentration of environment.
- Cells beside it get nitrogen and pass on progressively less to the next cell, causing more heterocysts to form.
There are 4 major historical stages of phycology. Describe 1 of 4:
- Early Greeks to mid 1700’s.
- Was anything known about algae?
Very little knowledge, only macroscopic algae could be studied.
Ancestral gram-negative cyanobacterium had ___ membranes.
Ancestral gram-negative cyanobacterium had two membranes.
Carbohydrates in chromophyta (diatoms):
Beta-1,3-linked glucan (laminarin, chrysolaminarin)
In algal morphology, a species can be irregular (also colonial); define this.
Unknown number of cells, or goes not have a fixed number, or does not have a set shape.
Describe this type of sexual reproduction in algae:
- Anisogamous
Anisogamous: Morphologically dissimilar.
*exam
Describe each word in the pair as they pertain to the subject matter of this course, and explain the difference between them.
Zoospore / Aplanospore
A zoospore is a motile, asexual reproductive structure whereas an aplanospore is a nonmotile, asexual reproductive structure.
Some suggest phylogenetic affinities based on photosynthetic pigments.
Describe the fucoxanthin series in terms of:
- What 3 similarities are present between the members of the group (Phaeophyta, Chrysophyta, Bacillariophyta)?
- All contain yellow-brown-orange fucoxanthin pigment
- All produce laminarin and chrysolaminarin
- All produce motile stages somewhere in lifecycle
What does it mean if algae is phytoplankton? What if it’s benthos?
- Phytoplankton = algae floating in water
- Benthos = found in a substrate
Define: Costae
- Diatom frustule component
- More heavily silicified ribs between rows of striae
Describe this algal flagella type:
- Haptonema.
What is the structure, function, and which division is it exclusive to?
Haptonema: Superficially resembles flagellum but different internal anatomy (no 9+2 microtubular structure).
- function uncertain but may be used for defence, food capture, or attachment.
- exclusive to Division Haptophyta.
What is different about chlorophyll F?
- Light absorption in the infrared spectrum (like bacteriochloropyll) which is in some bacteria, possibly intermediate stage in evolution?
- Anoxygenic
In algal morphology, a species can be filamentous, and may be “true or false”; define this.
True branching is when the alga grows in a new plane (second plane). During division the two cells still remained attached and created a radiating pattern of branching, in a second plane.
False branching is when serrate algal may get stuck together and appear branched but aren’t (ie. caught together by a common coat of muscilage). The second filament is not actually connected but remains attached due to the coating.
Describe the flagella and eyespot of chrysophyceae in terms of…
- Type of flagella(e)
- Arrangement (perpendicular or paralel)
- Flagella make up (__+__ microtubular arrangement)
- Presence of photoreceptor? What is this? What does it detect?
Many have tinsel flagellum with tubular hairs (mastigonemes) and whiplash flagellum (no hairs or very fine hairs) inserted perpendicular to tinsel
Whiplash flagellum usually shorter and sometimes serves no role in motility
Both flagella with typical 9+2 microtubular anatomy - 9 pairs of microtubules around perimeter of flagella and 2 main microtubules within it
Whiplash flagellum has swelling at base which contains photoreceptor (electron-dense area)
Eyespot (in or near chloroplast) and flagellar swelling interact in response to light direction (phototaxis)
Medulla in phaeophyceae
in the middle of the algae, used primarily for storage and transport (no photosynthesis)
Describe: Radioisotopes (and stable isotopes).
- Radioisotopes are elements with different numbers of neutrons compared to the “normal” form. Some are stable, some must decay to stable elements.
- Most useful are 13C, 14C, 15N, 23P, 33P, 34S.
- Used to study physiology (carbon fixation and partitioning, nitrogen fixation), and ecology (community photosynthesis, trophic dynamics).
Some suggest phylogenetic affinities based on photosynthetic pigments.
Describe the fucoxanthin series in terms of:
- Which 3 groups are part of it?
-Phaeophyta, Chrysophyta, Bacillariophyta
Araphidinate vs Monoraphidinate vs Biraphidinate vs Pseudoraphidinate
Araphidinate: no raphe on either valve
Monoraphidinate: raphe on one valve
Biraphidinate: raphe on both valves
Pseudoraphidinate: clear area in centre of valve without fissure
What are 3 reasons an algae may have mucilage (they don’t all have to apply, but 3 reasons)?
- Protection from desiccation (mucilage is mostly water).
- Protection from grazing (by herbivores, makes the algae bigger, and they may chose not to eat it because mucilage is low in nutritional value).
- Buoyancy (greater S.A. = more drag = sinks slower).
Contribution of Ralph Lewin, Dr. G’s hero!
- found an organism unidentifiable that didn’t fit into classification systems and spurred the revolution=
Prochloron or Prochlorophyta (before Chlorophyta, green algae); intermediate step in eukaryote evolution - translated Winnie the Pooh into Esperanto (create an international language, simplified language easier to learn, to make it easier to communicate with everyone around the world)
- first to write a book in the field of coprology (scientific study of fossilized feces)
If the classification name of an algae ends with _____, which hierarchical level is it?
- ales
Order.
Diatoms can be phytoplankton or benthic.
There are 2 subgroups of benthic diatoms, describe:
Haptobenthic.
- Associated with a firm surface (wood, rock), can’t burrow into the surface
- Diatoms are glued onto the surface of the sand (in a crevice), to prevent separation from it, bumped around by other grains of sand during tides
- Adenate diatom = glued to surface
- May use raphe (mucilage), or a stalk
Describe lake blooms/ Cyanobacterial blooms in terms of:
- Effects on humans.
- Aesthetic impairment, and gross taste and odour too.
- Produce toxins: dermal and oral uptake (typically low GI absorption) but no known antidote or method of removal from contaminated water.
- Sublethal symptoms include vomiting, diarrhea,
abdominal cramps, headache, excessive bronchial
secretions, difficulty breathing, dizziness, coma, permanent memory loss. - Often neurotoxins and hepatotoxins.
Describe this modified plasma membrane (algal cell covering):
- Frustule (shell) in terms of…
- What are the 2 valves called? How are they connected?
- Composed of two interlocking valves (epitheca, hypotheca) connected by one or more cingular bands (girdle)
- Epitheca is the bigger of the two and covers the hypotheca
- Frustular morphology is basis for diatom classification
- Like a Petri dish on the outside of the cell membrane
Auxospore
A means to escape adversity of the environment
Define: Glaucophyta (what are they equivalent to?).
Endosymbiotic cyanobacteria (cyanelles) rather than chloroplast.
There are 4 major historical stages of phycology. Describe 3 of 4:
- 1880’s to early 1950’s.
- How was algae knowledge increased during this type?
- Who published an algae index that is still used today?
- Improved microscopic quality and increasing study of microscopic algae (as a hobby or professionally).
- Giovanni de Toni created an index (Sylloge Algarum/ Summary of Algae) which classified algae based on observable features.
Nitrogenese
Reduces N2 to ammonia (NH3), is poisoned by oxygen so must be in an oxygenic environment.
Not specific to N2, it can also reduce acetylene to ethylene.
Microevolution vs Macroevolution
Microevolution: small microscopic changes
Macroevolution: large changes
If you see a diatom with lots of processes, what would this tell you about its habitat?
- Processes = long spines
- Use them for buoyancy, so this diatom is very likely planktonic
- Exam question *
Why do diatoms produce a cyst?
They progressively get smaller with each instance of sexual reproduction, so they create a cyst (sexual reproduction), which restores them to a larger size.
What is different between gram negative and gram positive bacteria (staining, membrane chemistry).
- Gram negatives have peptidoglycan in their membranes, so won’t stain purple with crystal violet.
- Gram positives stain purple
What is the function of accessory pigments?
Maximizes energy intake, particularly in PSII.
Describe asexual reproduction in chrysophytes.
- cells divide mitotically to form 2 daughters through simple cell division.
- cells sometimes lose flagella prior to division and daughters may lack them for a time afterwards.
In cyanophyta, all groups except Chamaesiphonales have gas vacuoles (pseudovacuoles).
Describe what they are.
Self-erecting cylindrical vesicles containing atmospheric gases
Accumulation of photosynthate increases cell turgor pressure, causing collapse of gas vacuoles
- good exam question *
Name an algal group that is haptonemous.
Division haptophyta.
Describe (very basic) this diatom frustule ornamentation:
Processes (rimoportulae)
(functions are on a different card).
- Solid protrusions on inner or outer valve face (looks like a zipper)
Simple dichotomous key
system of identification, two alternatives offered, follow the key to find out which organism it is based on yes or no questions, look at two alternatives and find which one corresponds to the organism
Chlorophylls A, B and C are all oxidized forms of ______.
Chlorophylls A, B and C are all oxidized forms of bacteriochlorophyll.
Define: thermophilic
Loves high temperatures
Cell wall of phaeophyceae (in detail)
Complete cell wall is well-developed, composed of two layers:
- Inner, rigid layer of cellulose fibrils and alginic acid/alginate; highly hygroscopic polysaccharide absorbs 200-300X its weight in water); thickness varies between species
- Outer, slimy, amorphous layer of algininate (97%) and fucoidan (sulfonated polysaccharide), which helps to protect against desiccation, pounding surf, temperature.
- Alginic acid confers flexibility to thallus, helps prevent desiccation, and functions in ion exchange
Diatoms can be phytoplankton or benthic.
What are phytoplankton diatoms, and what do they require? What adaption may they have?
- Float in water column, no attachment.
- Requirement for high silicon levels to make their frustule, levels may correspond to diatom blooms.
- Often have abundant outer processes (giant spines) for buoyancy. Can get caught in fish gills and cause them stress.
Describe in general, the chloroplasts of diatoms in terms of:
- How are thylakoids arranged?
- Pyrenoids? If so, how are they arranged?
- Thylakoids grouped in three (lamellae) with girdle lamellae present
- Each chloroplast contains one to several pyrenoids, located centrally or peripherally
Diatoms are important to 2 marine communities, list them. How much of earth’s primary productivity do they contribute to?
- Important component of planktonic and benthic. communities
- Some sources suggest marine diatoms account for
20-25% of total primary production on Earth
Chloroplast (basic structure, what their membranes tell us, how many chloroplasts algae can have)
- Basic structure is 2-4 layered membrane-bound vesicle enclosing thylakoids in matrix (stroma)
- Number of membranes is a clue of their evolution, so more membranes = more advanced organism (not primitive)
- Can have 0 - many chloroplasts, shapes vary.
Blade / Frond
- Is deciduous, being shed each year
- Like the leaves in higher plants in phaeophyceae (brown algae)
What algal group is thought to have the most species?
Diatoms, up to 100,000 but that’s under debate.
Describe primary endosymbiosis.
Primary endocytosis:
- A free living heterotrophic prokaryote engulfs (with its membrane) and retains a gram-negative cyanobacterium (instead of digesting it).
- Have 2 membranes and peptidoglycan between them.
- The phagosomal membrane was lost.
E3 Live (Aphanizomenon flows-aquae)
*not vital
- Food supplement
- Wild-harvested is worrisome due to not being grown in a controlled environment
most common morphology and flagella in: synurophyceae
Flagellated unicells and colonial
List 3 modes of nutrition in chrysophyta (classes synurophyceae and chrysophyceae).
- Photolithotrophy (common)
- Phagotrophy
- Mixotrophy
Describe what a Lorica algal cell looks like.
- Looks like a wine glass or trumpet shaped cell with an opening at the end or conical sheath - cell wall doesn’t go all the way around the cell.
How do diatoms form symbioses?
- Symbiotic cyanobacteria within diatoms includes Rhopalodia, Epithemia, Rhizosoleni.
- other organisms: Nitzschia frustulum in Foraminifera (amoeboid protists): no frustule when inside host but regenerate them when released into culture medium. Photosynthetic ability, they generate sugars for foraminifera.
Describe chloroplasts in division chrysophyta (classes synurophyceae and chrysophyceae) in terms of:
- Number of chloroplasts per cell
- Which photosynthetic pigments are present
1 or 2 peripheral chloroplasts per cell
Chlorophylls A, C1 (& C2 in chrysophytes) with various carotenoids, mostly fucoxanthin but sometimes carotene and xanthophyll
What are 2 purposes of sexual reproduction in diatoms?
- Restore original size to the population
- To survive adverse environmental conditions
What kind of sexual/diplontic reproduction occurs in centric (2) vs pennate diatoms?
- Centric: oogamy - larger immobile egg, smaller motile sperm.
- Pennate: Isogamy - 2 similar gametes.
To summarize Lee’s classification, there are 4 main algal groups.
- Eukaryotes with chloroplasts surrounded by 1 membrane of chloroplast ER:
- 2 divisions.
Divisions Euglenophyta, Dinophyta.
What type of flagella is found in division chromophyta (except for diatoms)?
heterokont
Define: Oxytrophy.
Has a requirement for some organic material that it can’t create itself, despite being an autotroph (kinda like humans can’t make all amino acids).
Define: Aplanospore.
A non-motile stage of asexual reproduction.
If the classification name of an algae ends with _____, which hierarchical level is it?
- Phyta
Division.
Chromophyta can be palmelloid, in the context of this division, what would that mean?
Palmelloid – non-flagellated cells, usually naked, embedded in common envelope of mucilage
Pseudoparenchymatous
Filamentous 3D mass of cells in which individual filaments are difficult to distinguish
List the 2 types of projectiles in the division chrysophyta (classes synurophyceae and chrysophyceae).
- Muciferous bodies
2. Discobolocytes
Who’s classification do we currently use for algae (1999)?
Lee.
how are cysts/statospores beneficial for studying things?
Persist in lake sediments and, due to ornate pattern on external surface, are diagnostic for species that produced them
Describe this modified plasma membrane (algal cell covering):
- Pellicle.
- What division has it?
- Interior or exterior?
- Exclusive to Euglenophyta (euglenids)
- internal
- corrugated membrane with strips of protein in each depression followed by microtubules; in the grooves are muciferous bodies; mucilage acts as a lubricant to help the cell twist and untwist to help with friction and create propulsion= Euglenoid motion
Algal Distribution: Aquatic
a) Phytoplankton
b) Neuston
c) Metaphyton
d) Periphyton
a) Phytoplankton (free floating)
b) Neuston (air-water interface, Euglena sanguinea)
c) Metaphyton= elephant snot (formerly attached)
d) Periphyton (attached, any algae associated with a surface like plastic, a car, an artificial or human surface)
Which algal group has chlorophyll C, in addition to A?
some Rhodophyta
first phase in algal growth
lag phase
Describe: Transmission Electron Microscopy (TEM).
Uses electrons to pass through an object, allowing you to see the ultrastructure (subcellular organization) as a cross section/inside view.
Algae can store glucose as a high molecular weight compound. There are 3 types of B-1,3 linked glucans, describe: Paramylon.
- What is it a polymer of?
- What algal group would have it?
Polymer of glucose, found in Euglenophyta.
Photosystem I vs II (which produces O2, and are there exceptions?)
Photosystem I is most primitive and evolved first, does not produce oxygen (anoxygenic).
Photosystem II evolved after, produces oxygen (oxygenic) by splitting water (how algae produced our oxygenic atmosphere).
*Only organisms with both photosystem I and II can produce oxygen, except in specialized cells like heterocysts that have PSI only
What’s a frustule? What kind of algae would have it?
A silicone shell surrounding the cytoplasm of diatoms.
diplontic lifecycle
Predominantly diploid lifecycle (2 copies per gene) but has a short-lived haploid stage.
Describe this type of projectile in the division chrysophyta (classes synurophyceae and chrysophyceae): Discobolocytes
Similar to muciferous bodies
Located in outer layer of cytoplasm; single membrane- bound vesicle with hollow, ring-shaped disc in outward- facing part
Explosive discharge with expansion of projectile into thin thread (6-11 μm long) with disc at tip
- Has a chamber with a little string and disc at the end and discharged out of the membrane (disc at the end of a string)
- Means of motility or anti-predator weapon
Axenic Culture
- does not contain foreign organisms (bacteria, etc), a pure culture
Phycobilin series vs Fucoxanthin series vs Non-Masked series (pigments)
Phycobilin series:
- Cyanophyta, Rhodophyta, Cryptophyta
- Red algal chloroplasts resemblemble cyanobacteria with pigments associated with a single membrane.
- No motile stages in lifecycles
Fucoxanthin series:
- Phaeophyta, Chrysophyta, Bacillariophyta
- All contain yellow-brown-orange fucoxanthin pigment
- All produce laminarin and chrysolaminarin
- All produce motile stages somewhere in lifecycle
Non-masked series:
- Chlorophyta, Euglenophyta, Xanthophyta
- Photosynthetic pigments not masked by accessory pigments
- Green produced by chloroplasts
How do cyanobacteria store starch?
Store polysaccharides as cyanophycin granules or myxophycean starch (α-1,4 linked glucans do not react to iodine to give blue-black colour)
List 4 major ways in which cyanobacteria affects humans.
- Atmospheric oxygen.
- Nitrogen fixation.
- Food (spirulina is very high protein)
- Lake blooms.
Algae are distributed in virtually every environment on earth. In terms of aerial/terrestrial environments, define this possible habitat:
- Cryophyton
On cold surfaces (not necessarily ice, but can be).
Describe the cell covering of division chrysophyta (synurophyceae and chrysophyceae) in terms of:
- Naked or covered? What does this mean?
- What kind of cell wall? (note, not the scales, that’s another card)
- Naked (no cell wall)
- Incomplete cellulose-based cell wall (lorica) forms sheath in which naked cell is contained
- Has scales (another card)
All photosynthetic algae use _____ to produce ATP and NADPH (but some ____ forms).
All photosynthetic algae use chlorophyll to produce ATP and NADPH (but some achlorophyllous forms)
By how much do diatoms shrink when the smallest daughter cell divides?
1/2 size every single time the smallest diatom divides
What kind of xenogenous development did glaucophyta have?
incorporation of blue green prokaryote
If the classification name of an algae ends with _____, which hierarchical level is it?
- phyceae
Class.
Define: Lorica.
- Which 2 divisions may have this?
- Incomplete cell wall.
- Seen in some Chrysophyta and Euglenophyta.
Most common colour of these…
- Division cyanophyta
- Division chromophyta: Class bacillariophyceae (diatoms)
Division chromophyta: Class Cgrysophyceae (chrysophytes)
- Cyanobacteria are blue green
- Chromophyta are golden-brown
In algal morphology, a species can be coenobial (also colonial); define this.
Has a fixed number of cells.
- May be multiples of 2, for example.
Primary Endosymbiosis vs Secondary Endosymbiosis
Primary endocytosis:
- A free living heterotrophic prokaryote engulfs (with its membrane) and retains a gram-negative cyanobacterium (instead of digesting it).
- Have 2 membranes and peptidoglycan between them.
- The phagosomal membrane was lost.
Secondary Endosymbiosis:
- The resulting organism from primary endosymbiosis is again phagocytised, but this time the phagosomal membrane persists - so there are now 4 possible membranes.
- Some group have lost 1 membrane, so they have 3.
There are 2 theories of how eukaryotes formed.
Describe: The xenogenous theory.
- Evidence?
Xenogenous theory:
- Prokaryotes obtained organelles via series of endosymbioses (cells eat other cells) with other prokaryotes
- Mitochondrion and chloroplast have their own extranuclear DNA, and divide autonomously from nucleus via binary fission (like Bactria)
- Glaucophyta contain endosymbiotic cyanobacteria (cyanelles) that perform chloroplast function
- Some dinoflagellates also contain endosymbiotic cyanobacteria (phaeosomes)
Describe this general feature of algae:
- No differentiation of parts.
- Algae (if multicellular) exist as an undifferentiated mass of cells, called a thallus.
- No specialization, all cells are the same (compare to stems, roots, leaves, etc of plants).
- Rarely is there evidence of coordinated activity.
Compare these 2 diatom types (centrics and pennates) based on the following characteristic:
- number of chloroplasts
- Centrics: Many chloroplasts per cell
- Pennates: One or two chloroplasts per cell, maximum of 4.
Describe secondary endosymbiosis.
Secondary Endosymbiosis:
- The resulting organism from primary endosymbiosis is again phagocytised, but this time the phagosomal membrane persists - so there are now 4 possible membranes.
- Some group have lost 1 membrane, so they have 3.
in the sexual reproductive cycle of dinobryon (chrysophyte), are they monoecious or dioecious? iso, aniso, or oogamous?
- how do the males find the females?
- Dioecious (Male and female)
- Anisogamous
- Naked male gamete attracted by erogen released by female cells (like a pheromone/chemical attractant). The males swim to her, she remains in the lorica.
Shapes:
A) discoid
B) stellate
C) reticulate
A) disc shaped like a coin
B) star shaped
C) net shaped
Resting cell and compare to vegetative cell in diatoms
- Common in freshwater, pennate diatoms
- Similar in appearance to vegetative cell with fewer mitochondria and larger lipid bodies
- Sink to bottom of water body, remain viable > 2 months
- Cell not doing anything
- Frustule is unchanged
How do diatoms have forensic implications?
- Diatom frustules are persistent in aquatic environments so can help determine where a drowning occurred
- Diatoms enter lungs at time of drowning then distribute to other parts of the body
- Tissue samples are collected from victim’s bone marrow, lung, spleen, liver, kidney, brain
- Digested to remove organic matter and leave frustules
- Diatoms identified and matched to those at prospective crime sites
In algal morphology, a species can be multicellular; define this.
Has cells modified for specific purposes.
Autotroph vs heterotroph
Autotroph: Feeds themselves using solar energy and inorganic nutrition.
Heterotroph: can’t feed themselves so rely on other organisms for organic material:; can be obligate or facultative (able to switch).
Algae can store glucose as a low molecular weight compound. Describe: Glycosides.
- List 3/4 types of glycosides.
- 1 Algal group that would use this.
Glycerol, glycosides, floridoside, and isofloridoside.
Found in Rhodophyta.
What does metalimnetic blooms/deep peaks mean in terms of chrysophytes?
Metalimnion: intermediate layer (not at the surface, not in deep water), allows for both light and higher nutrient level, best of both worlds, facultative heterotrophs/mixotrophs found here due to capturing the dying algae that are sinking towards the bottom of the lake= Metalimnion Blooms
- also possibly a way to escape predators
Describe the cell covering of division chrysophyta (synurophyceae and chrysophyceae) in terms of:
- 2 types of scales (materials)
- Inorganic (silica) or organic (carbohydrates).
How are diatoms a Paleoenvironmental Indicator? Describe the A/C ratio.
- Ratio of araphidinate pennates (A) to centrics (C).
- Assumption that centrics are typical of oligotrophic (nutrient-poor) conditions whereas araphids are typical of eutrophic (nutrient-rich) conditions
- When A/C ratio low, taken as indicator of relative oligotrophic conditions, whereas high A/C ratio indicates eutrophy
Algae can store glucose as a low molecular weight compound. Describe: Sugars.
- What form, for what?
- 2 Algal groups that would use this.
Sucrose, as reserve product.
Found in Chlorophyta and Euglenophyta.
flagella in paeophyceae
like all chromophytes, heterokontous (tinsel, whiplash) but is only flagellated in some sexual repro stages, the vegetative stage does not have any flagella
- Long anterior, tinsel flagellum with tripartite hairs and shorter, posteriorly-directed whiplash flagellum
- Posterior flagellum usually has swelling near base (photoreceptor)
- Eyespot present in chloroplast of some taxa
What favours cyanobacteria in lake blooms? 4 things.
- Well adapted to high water temperatures and low light intensity occurring in summer blooms
- N fixation gives them advantage when N is low (but not all bloomers can fix N)
- Gas vacuoles provide buoyancy which keep them suspended in well-lit, surface water
- Mucilage provides protection from grazing
What does it mean if a flagella is apical, sub apical, or from a pit?
- Apical: attached to apex (top).
- Subapical: attached near apex.
- From pit: attached elsewhere.
What’s a phototactic response, and what is used to achieve it? In what algae?
- Involved in motility by sensing light to direct the euglena towards or away from light = phototactic responses
Describe the exponential growth phase in growth.
rapid growth
growth rate detemrined by genetics and environmental conditions
Describe this algal flagella type:
- Heterokontous.
Heterokontous: Dissimilar flagella (more than 1), of unequal length, and/or one smooth and one hairy (“tinsellated”).
Define: Grana.
Stacks of thylakoids make up grana (various degree of stacking in different groups, more stacking in complex groups).
Describe: Scanning Electron Microscopy (SEM).
An object is coated with a thin layer of metal, electrons used to create a 3D image of the exterior.
What does it mean if a flagella is hemodynamic vs heterodynamic?
hemodynamic = orientated in same direction. heterodynamic = orientated in different direction.
final yield in growth culture
Maximum culture density is the Final Yield (occurs in stationary phase)
Describe: Chromatography.
- Separation based on differences in polarity of a single molecule (influences how it travels in a solvent).
- Useful for examining biochemistry (composition of pigments, fatty acids, amino acids, nucleic acids).
Oligotrophic vs Eutrophic Conditions
Oligotrophic: poor nutrient conditions, nutrient poor and chemically-dilute water
Eutrophic: nutrient rich conditions
What is the mechanism and result of asexual reproduction in diatoms?
In the parent…
- Original valves both become epivalves in daughter cells.
- Two new hypovalves are produced.
Result:
- One daughter is same size as its parent, other is (slightly) smaller
Auxotrophy
- require one or more organic nutrient (vitamins) that the organism can’t produce themselves.
Describe this general feature of algae:
- Vegetative reproduction is common.
- Mostly asexual/vegetative reproduction.
- Some alga have no known sexual reproductive system.
- Cryptogamic plants (no true flowers or seeds).
How are diatoms a Paleoenvironmental Indicator?
(*not A/C ratio).
- Diatoms are abundant and have rapid response to environmental change + Distinct ecological requirements and tolerances to water quality.
- Frustules resistant to decay so accumulate in sediments = record of past ecological conditions
- Can take sediment sample to make calibration set, determines which algae were present in samples and then compared to their preferred salinity (then tells you salinity in body of water at a time, as well as water levels. High water levels causes low salinity, low water levels = high salinity).
Describe the flagella and eyespot of synurophyceae in terms of…
- How they differ from chrysophyceae (otherwise all the same).
Similar to Chrysophyceae except:
Flagella inserted approximately parallel to each other
No eyespot
Contractile vacuole opposite not by flagella
How dictyocha (chrysophytes) can harm fish
Marine Dictyocha causes fish mortality, possibly due to oxygen depletion and damage to gills by siliceous scales
Describe the death phase in growth.
dying cells release nutrients which may promote further growth
extent of recycling determines rate of death phase and possible stabilization of cell density
Algae are distributed in virtually every environment on earth. In terms of aerial/terrestrial environments, define this possible habitat:
- Endozoic.
Live inside animals (ie. can give them a green colour)
Describe this modified plasma membrane (algal cell covering):
- Cell wall.
- What are the 2 parts?
-Generally comprises two parts: fibrillar part (skeleton) and amorphous part (matrix in which fibres embedded)
Paralytic Shellfish Poisoning (PSP)
- Where is absorbed in the body?
- What are side effects?
- Domoic acid passes through gastrointestinal tract with little or no absorption but very potent in minute
quantities - Initial symptoms in 30 minutes to 24 hours (similar to microcystins): vomiting, diarrhea, abdominal cramps, headache and, in severe cases, excessive bronchial secretions, difficulty breathing, loss of equilibrium, coma, permanent (irreversible) memory loss and death
Describe this method of asexual reproduction in algae.
- Spores (3 subtypes)
- can be mobile (planospores, zoospores)
- non-mobile (aplanospores)
- spore-producing cell (sporangium).
In what ways are cyanobacteria similar to bacteria? 4 main reasons.
Prokaryotic ultrastructure (DNA free in nucleoplasm, lacks histones)
Cell walls contains muramic acid, making both groups sensitive to antibiotics (blocks muramic acid synthesis) and lysozyme (destroys CH2O in cell wall)
Chemoheterotrophs, photoheterotrophs, obligate photolithotrophs
Some fix N2 to NH3 via nitrogenase
Describe this modified plasma membrane (algal cell covering):
- Frustule (shell).
- What division has it?
- Composition?
- Interior or exterior?
- Exclusive to Bacillariophyceae (diatoms, from Greek “diatomos”= cut in two)
- Made primarily of polymerized silica with some organic (sugars, lipids, amino acids)
- Exterior to plasma membrane
Some suggest phylogenetic affinities based on photosynthetic pigments.
Describe the phycobilin series in terms of:
- Which 3 groups are part of it?
• Cyanophyta, Rhodophyta, Cryptophyta
Describe the stationary phase in growth.
net growth and death is the same.
Filament is the term normally used for linear arrangements of cells. In cyanophyta (and this group only), what are filaments instead called? What is an exception?
- Called trichomes.
- Exception is only if they’re covered in a sheath (trichome + sheath) = filament.
Heterogeneous (and how it relates to algae).
Very diverse groups.
Algae, pond scum, water moss, seaweed, etc. is considered a very heterogeneous group.
If the classification name of an algae ends with _____, which hierarchical level is it?
- aceae
Family.
In algal morphology, a unicellular species can be rhizopoidal/amoeboid, what does this mean?
- Not a standard form/dissimilar shape (Rhizopoidal).
- Shape changes or is not constant (Amoeboid).
Algae are distributed in virtually every environment on earth. In terms of aquatic environments, define this possible habitat:
- phytoplankton.
free floating in water
In terms of the accessory pigment carotenoid, which alga phyla would have this type: Fucoxanthin (3)?
Chromophyta, Haptophyta, Dinophyta
pigments in phaeophyceae
chlorophyll A, C1, C2, fucoxanthin
Algal Distribution: Aerial and Terrestrial Environments
a) Symbioses b) Animals c) Epilithon d) Edaphic e) Sympagic f) Cryophyton g) Epixylon h) Epiphyton or epiphytic
a) Symbioses (lichens)
b) Animals (endozoic=living inside animals)
c) Epilithon (rock surfaces)
d) Edaphic (soil)
e) Sympagic (with ice)
f) Cryophyton (cold surface)
g) Epixylon (wood surface)
h) Epiphyton or epiphytic (algae living on plants)
Do unicellular and colonial algae fix nitrogen?
No (must live in high nitrogen environment)
Describe 4 main functions of this diatom frustule ornamentation:
Processes (rimoportulae)
- Holds cells together in chains (zipper like)
- Reduce sinking rate (by increasing surface area)
- Discourage grazing (can be large, spine like and get caught in fish gills)
- Mucilage extrusion (can be tubes where mucilage can exit)
Define: Thallus.
- Algae (if multicellular) exist as an undifferentiated mass of cells, called a thallus.
- No specialization, all cells are the same (compare to stems, roots, leaves, etc of plants).
Define: Trichome (general).
What is the only division that has trichomes?
- Trichome: linear chain of cells, that are not surrounded by a mucilage coat.
- Only in cyanobacteria.
Compare these 2 classes (synurophyceae and chrysophyceae) in division chromophyta in terms of….
- Flagella position
- Synurophyceae: Parallel (homodynamic)
- Chrysophyceae: Perpendicular (heterodynamic)
Describe sexual reproduction in chyrsophytes in terms of, is it common? what type is it (oogamous, etc)? Are gametes flagellated? What’s produced?
- Uncommon; seen in Dinobryon and Synura
- Isogamous, flagellated gametes
- Results in production of sexual statospores
Anoxygenic vs Anaerobic
Anoxygenic: carrying out photosynthesis where no oxygen is produce as a byproduct
Anaerobic: requires the absence of oxygen (can’t live in oxygen)
Describe lake blooms/ Cyanobacterial blooms in terms of:
- Why/when they occur.
- Common genera (not vital).
- Effects on fish and other life.
- Poor food web support.
- Occur when nutrient enrichment, especially N and P, favours excessive growth.
- Common genera include Microcystis, Anabaena, Aphanizomenon, and others
- Depletes oxygen (produces lots while growing, but uses way more when dying and decaying. Even more of a problem in winter when an ice later prevents oxygen from diffusing in).
- Herbivores don’t eat lots of algae (taste bad, mucilage).
In terms of the accessory pigment carotenoid, which alga phyla would have this type: Beta-carotene?
Majority of them.
What shell feature is exclusive to bacillariophyceae (diatoms)?
- Single most distinctive feature is the silica shell enclosing the plasma membrane, the frustule:
- Exclusive to Bacillariophyceae (diatoms)
Made primarily of 95% silica with various metals (Al, Fe,
Ge) and some organics (sugars, lipids, amino acids)
Trumpet Cells
- Long chains of trumpet cells, with holes in them to allow flow in between cells
- In stipes of kelp
- Trumpet cells is very similar to phloem seen in vascular plants
- ** in brown algae **
What kind of xenogenous development did cryptophyta have?
incoropotation of univeullar red alga by heterotrophic flagellate
Cyanobacteria can be thermophilic. What is the approximate maximum temperature range for them, and how does this compare to other organisms?
~74C, compared to eukaryotes that can’t live beyond 50-55C. Prokaryotes can tolerate hotter temperatures. Cyanobacteria are one of the most heat tolerant organisms.
Describe resting cells as diatom reproduction.
- Common in freshwater, pennate diatoms
- Similar in appearance to vegetative cell with fewer mitochondria and larger lipid bodies
- Sink to bottom of water body, remain viable > 2 months
Are diatoms flagellates?
As a whole, they’re non-flagellate except during sexual reproduction of one group (centrics, which have flagellated male
gametes called swarmers).
Often have other modes of motility (like group pennates).
Describe the diatom frustule structure in terms of:
- Epivalve and hypovalve
- two valves of the frustule in Diatoms:
Epivalve: larger valve, also called epitheca
Hypovalve: smaller valve, also called hypothecate
For botanists, what is the classification categories from kingdom to species (7)?
- Kingdom.
- Division (instead of phyla).
- Class.
- Order.
- Family.
- Genus.
- Species.
There are 4 major historical stages of phycology. Describe 2 of 4:
- Mid 1700’s to 1880’s.
- Who formalized the taxonomic systemization and what did this lead to? How was algae studied?
Linnaeus did, this lead to formal algal nomenclature. He was the first to use the world “algae”. Linnaeus described mostly macroscopic forms (due to poor microscopes) and grouped algae with fungi, and lichens.
Define: Gas vacuoles (function, where they’re found).
- False vacuoles or pseudovacuoles (vacuoles are organelles so wouldn’t be in prokaryotes, this is the prokaryote version of it).
- Found only in cyanophyta (cyanobacteria).
- Functions to regulate buoyancy.
- good exam question *
Prokaryote vs Mesokaryote vs Eukaryote
Prokaryotes: coiled DNA, no nucleus or other organelles
-Mesokaryotes: chromosomes but no interphase and no histones, organelles, intermediate nucleus (intermediate in evolution of prokaryotes and eukaryotes)
Eukaryotes: chromosomes, nucleus and other membrane-bound organelles
Chloroplasts in chromophyta (diatoms):
Thylakoids in three (lamellae), envelope with two membranes
Scale symmetry of Synurophyceae
- Synurophyceae – bilateral with multiple parts (dome, shield, bristles/spines), precisely arranged in pattern
____ are a major constituent of most aquatic habitats where they may represent > 80% of algal biomass.
diatoms
