Lecture 1 RH Algae Flashcards
What are lichens a symbiosis between?
Lichen are between bacteria and fungi
What happened to algae to allow plant formation?
Natural selection to allow algae to survive on land
What kinds of differences and similarities are investigated when classifying organisms?
Morphological
Genetic
Biochemical
Others
What is the evolutionary origin of land plants?
Most plants originated from ancestral green algae
What is true about ALL plants?
- They are prokaryotic and eukaryotic
- They are all multicellular
- They are green coloured and land dwellers
- The contain chlorophyll
- They are photosynthetic
- They are photosynthetic
What is the evolutionary origin of oceanic plants?
Red algae
What are the similarities between ancestral algae and modern plants?
Ancestral green algae had both primary and accessory photosynthetic pigments.
Starch
Cellulose
Multicellular
Alteration of generations (goes between regeneration and reproduction)
What are cyanobacteria classified as?
Cyanobacteria used to be defined as plants but now are defined as bacteria
What are some uses for algae?
Can be used as indicators of clean water
Can be used for food and biofuel
Can be used to produce agar
Can be used to make biofuels
What are the types of water environments in which plants live?
Freshwater
Brackish water (0.5 - 30 ppt)
Seawater (30 - 50 ppt)
How are algae classified?
Morphology
Pigments
Chloroplast structure
Food store
Cell wall composition
Flagellation
How diverse are algae?
72000 species identified
What are the types of morphology that algae have?
Colonial (clustered together)
Capsoid
Coccoid
Palmelloid
Filamentous (Forming strands)
Parenchymatous
Chloroplasts in higher plants evolved from which of the following?
Brown algae
Golden algae
Red algae
Green algae
Blue green algae
Green algae
Where did brown, golden, and blue green algae evolve from?
Brown algae, golden algae, and blue green algae evolved from ancestral green algae.
What is the dominant algae in clear oligotrophic water?
Bacillariophyta (aka diatoms)
What is the most common type of phytoplankton?
Bacillariophyta
What are the close relatives of bacillariophyta?
They are closely related to brown algae
What is the morphology of bacillariophyta?
Unicellular or colonial (in chains)
What are some other features of bacillariophyta?
They contain oils making them potential biofuel producers.
They are not mobile (only male gametes have flagella)
They mostly reproduce via mitosis
What pigments do bacillariophyta contain?
Chlorophylls a+c
Carotenoid = fucoxanthin
Close relatives of Phaeophyta (aka brown algae)
What does phytoplankton usually refer to?
Microscopic plant cells
What is the bacillariophyta cell wall made up of?
silica = frustule
What do bacillariophyta look like?
Porous and exist as 2 half shelves enclosed in frustule.
With a raphe they have a pennate shape
Without a raphe they look like circles
What feature makes bacillariophyta good indicators of clean water?
Bacillariophyta are sensitive to pH
Why are algal blooms dangerous to consume?
algae produce neurotoxins that can be harmful
What pigments do golden algae have?
chlorophylls a, c1+c2
Carotenoids = fucoxanthin
What cell wall encloses chrystophyta (golden algae)?
cellulose
Are chrystophyta (golden algae) motile?
Some are some aren’t
What water do chrystophyta (golden algae) prefer?
Clean, low nutrient waters
How do chrystophyta reproduce?
Mostly asexually via mitosis
Sexual reproduction in some species causes silicon-containing cyst formation.
What are the types of chrystophyta?
Unicellular
colonial
siphonous (hollow tubular columns)
2 families chrysophycae + xanthophyceae
What type of organization do chrysophyceae have?
Planktonic (suspended in the water)
What type of organization do xanthophyceae have?
benthic (sit at the bottom of the water in very deep waters)
Do chrysophyta cause algal blooms?
yes particularly prymnesium parvum and these blooms cause death of fish and other creatures.
Where can green algae typically be found?
Mostly aquatic
Very diverse in form and habitat
What kind of pigments do green algae have?
chlorophyl a and b
some have other pigments like carotenoids and other pigments
*Not all green algae are green
What formations can chlorophyta have?
Unicellular and colonial
Are chlorophyta motile?
Some are some aren’t
What is the problem with the algae classification?
paraphyletic because it includes other algae but excludes plants despite being more closely related to plants
What are the 3 main types of green algae?
Chlorophyceae
Ulvophyceae
Charophyceae (this group contain desmids)
What do flagella indicate about circular forms of chlorophyta?
motility
What are desmids?
unicellular non-motile chlorophyta of order charophceae. They are used as indicators of clean water
What are the types of algae that are macroscopic?
Flat plate algae (Ulva aka sea lettuce)
Tube (enteromorpha)
What is the structure of macroscopic chlorophyta like?
Fill up in center and blow up at ends into utricles.
Filaments are centrally located
What does codium look like?
Finger like branching off a single stem and are siphonous
What is chlorophyta reproduction like?
Primitive algae have indistinguishable gametophytes and sporophytes that are motile.
Advanced algae are anisogamous (gametophytes are different). Male gametophyte is mobile and female isn’t motile.
What are the uses of chlorophyta?
Ulva (sea lettuce) is eaton worldwide
Coral reefs
Pollution indicators
What are cyanobacteria?
Ancestors of plants found 3.5 million years ago.
They are part of the bacterial kingdom.
What is the organization of cyanobacteria like?
Unicellular/colonial forming a filamentous structure which could be enclosed in a gelatinous sheath
What pigments do cyanophya contain?
chlorophyll a
Phycobillin (phyco cyanin and phycoerythrin)
How do cyanophyta translocate?
By gliding
What is the function of a heterocyst?
Nitrogen fixation for cyanobacteria use
Where are cyanophyta most common?
Fresh water and brackish water.
Found close to water surface
What are features of water containing cyanophyta?
Oily water
Smelly
Fishy taste
Unfit for drinking
Contain cytotoxins (cyclic oligopeptides and alkaloids)
What type of toxins do cyanophyta produce?
Cyclic oligopeptides and alkaloids (neurotoxins, hepatoxins, cytotoxins, endotoxins.
*Responsible for lots of cattle death.
Can cyanophyta be consumed?
Some species can be consumed such as spinulina
What pigments do dinoflagellates have?
chlorophyll a + c
Carotenoids (peridinin)
*are typically brown coloured
How do dinoflagellates move?
2 flagella which beat within 2 grooves.
theca of cellulose plates
1 trailing flagellum and one inside
Do dinoflagellates produce algal blooms?
Yes most common producers of toxic blooms in brackish and marine waters.
What kind of toxins are produced by dinoflagellates?
Dino toxin (saxitoxin which is a paralytic neurotoxin)
Alexandrium and karenia
How can the toxins produced by dinoflagellates reach humans?
via shellfish which act as carriers
they accumulate
Why is a great research interest taken in dinoflagellates?
Dinoflagellates are bioluminsecent
Dinoflagellates have the ability to reduce the effects of aging. (luciferase comes from here)
What pigment to euglenophyta contain?
Carotenoids
Chlorophylls a + b (grass-green)
How do euglenoids get their energy?
Via photosynthesis and phagocytosis
How do euglenoids reproduce?
Asexually via cell division
What is the eyespot’s function in euglenoids?
They can use it to detect light and move towards it
Where can euglinoids be found?
Typically in pulluted environments
What features make euglenoids different from other algae?
They are both phagocytic and photosynthetic showing they had both animal and plant traits
What are phaeophyta?
Brown algae which typically can be seen washed up on the beach
What do phaeophyta (brown algae) look like?
undifferentiated vegetative bodies
Brown
What pigments do phaeophyta contain?
Chlorophyll a and c
Carotenoids (fucoxanthin)
Where can phaeophyta (brown algae) typically be seen?
Floating in ocean water
What are characteristic features of phaeophyta (brown algae)?
Contain an air filled bladder which makes them float and carries them towards light (some are filamentous)
They are the largest algae in size
What structure do phaeophyta store glucose in?
vacuoles in the form of laminarin (a beta -1,3 glucose polymer)
What is the cell wall of phaeohyta made of?
cellulose
alginic acid which makes emuslifiers
sulphated polysaccharides which makes algae
What are some uses of agar?
Used to solidify media
How do phaeophyta reproduce?
sporic meiosis (motile haploid male and female zoospores which combine to fertilize and form diploid zygotes.
Some exceptions to this reproduction cycle such as the mode of reproduction of fucus.
What are the names of the developing cells that form male and female zoospores?
antheridium and oogonium
Where do rhodophyta (red algae) live?
96% of them in marine water
4% in fresh water
What is the red algae’s structure like?
Filamentous
2 major shapes; flat sheets, or 3d- branched
What are the main pigments in red algae?
chlorophyll a
Carotenoids
Phycobilins (R-phycoerythrin and R-phycocyanin)
How do Rhodophyta store glucose?
in floridean starch (amylopectin-like) which is glycogen like and is made up of an alpha 1,4 glucose polymer
What is the cell wall of rhodophyta made of?
cellulose (beta-1,6 polymer)
sulphated polysaccharides which can be made into agar and carrageenans
with some calcification in some rhodophytes
What are some uses of rhodophytes (red algae)?
Can be used to create agar
Can be used to make food (sushi made from these as well as rice crackers, and by the Irish as laver bread)
How do red algae reproduce?
Gametes and zoospores are same size and fertilize and form a zygote elsewhere.
What pigments do diatoms, chrysophytes, and phaeophytes have in common?
Fucoxanthin
How does the moon affect the environment? How does this affect algae?
Water levels (tide)
Low tide causes exposure of algae and in turn causes damage. High tide is more favourable for algae
How does moon affect algal dessication?
Littorial fringe (exposure to sprays only)
Eulittorial zone (exposure during low tide)
Sublittorial zone (below low tide, no exposure, always immersed)
Different types of algae have different abilities to tolerate exposure to dryness.
How does the sun affect dessication of algae?
clear water means light can penetrate further allowing algal pigments to absorb the light. This effect is depth dependent. Green -> brown -> red
Temperature and seasons affect algal diversity
How does pH affect algal diversity?
Affects photosynthesis
pH is greater in rock pools (>9) and stable in open water (8.1 - 8.3)
How can algae be used as biological pH indicators?
More acidic conditions promote filamentous algae appearance and decrease in planktonic algae.
Water below 5.8 result in most diatoms and algae to disappear
How can algal blooms be used to understand contents of the water?
Sewage, organic matter, and chemical fertilizers result in an increase in nutrient supply. (Low N:P ratio = cyanobacterial blooms; High N:P ratio = green flagellates and diatoms dominate.
Organic matter, nitrates of phosphates = increase in microcystis, scendesmus, hydrodictyon and chlorella
Oil pollution can be detected by several algae
How can algal blooms be used to measure heavy metals?
They can absorb heavy metals and several species can grow such as cladophora, chlorella and stigeoclonium
Which of the following are indicators of clean water?
Chlamydomonas
Cyanobacteria
Euglena
Scendesmus
None of the above
None of the above.
Desmis
golden algae
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