Download Nadia Langha Biology 106 Honors Project

Nadia Langha
Biology 106 Honors Project
Cyanobacteria
 Domain Bacteria
 Division Cyanophyta
 Cyanobacteria also known as BlueGreen Algae
-Cyano=blue
 Bacteria are more closely related to prokaryotic bacteria
than eukaryotic bacteria.
 Cyanobacteria were the first algae!
More Characteristics of
Cyanobacteria
 Cyanobacterial cells may be spherical or rod-shaped.
 Round bacteria = coccus & Rods = bacillus
 Many form colonies, long filaments of cells strung
together, in which every cell is capable of living alone and
carrying out all life functions.
 Colony formation led to multicellularity, that also occurs
in Kingdom Protista.
 They can be slimy or slippery due to a gelatinous layer
that surrounds their cell walls.
 They have a prokaryotic flagellum that allows
locomotion but can also glide with their gelatinous layer.
Effects of Cyanobacteria on
Humankind
 Cyanobacteria are autotrophs, or organisms that
don’t feed on other organisms, but make their own
food from solar or chemical energy.
Cell Types in Typical Chain
 Vegetative cells – photosynthesize and release O2 gas and


sugar.
Heterocysts – specialized and bigger cells that create:
An oxygen-free environment, that allows nitrogenase
enzyme to fix nitrogen.
Acts as a floatation device so strands rise to surface for
photosynthesis to occur.
Form weak points of attachment that break easily, leading
to new formation colonies.
Spores – tiny reproductive cells that can resist harsh
conditions that can grow into new filaments again after
being exposed to suitable conditions.
Cell Types in Typical Chain
 Vegetative cells
 Heterocysts
 Spores
Intro to Pictures & Examples of
Cyanobacteria as seen in Lab…
-Oscillatoria sp.
-Anabaena sp.
Oscillatoria sp.
Anabaena sp.
Not seen in Lab, but extra
examples of cyanobacteria…
-Spirulana
-Lyngbya
(These two still demonstrate
characteristics of
Anabaena/Oscillatoria)
Spirulana
Lyngbya
Habitats
 Cyanobacteria can occur in fresh water, where they
form pond scum, as well as salt water and moist
terrestrial environments.
 Important functions in different environments.
Nitrogen Fixation
 Enriches soil by converting N2 gas from the
atmosphere into nitrogen compounds – nitrogen
fixation.
 Makes proteins through nitrogen fixation.
 Nitrogenase - enzyme that fixes nitrogen that only
works in cells where oxygen is absent.
Photosynthesis
 Contains chlorphyll a, a light-capturing pigment
important in photosynthesis.
Photosynthesis (cont’d)
 Cyanobacteria uses light and CO2 from the
atmosphere to make food sugars.
 They then release O2 back to the atmosphere.
Lichens
 Lichens have a close association between a fungus and a
photosynthetic organism such as an alga or cyanobacterium.
 Alga or cynaobacterium supplies food for the lichen from its
photosynthetic activity.
 Fungus anchors lichen to the substrate, encloses the chlorophyllbearing organism in a moist environment, and gives it necessary
nutrients (e.g. nitrogen & phosphorus) to survive.
 True symbiotic relationship: the fungus could live without the
photosynthesizer, but it would be limited by food availability;
the algae/cyanobacteria could live without the fungus, but it
would be limited by water/moisture availability. Together they
can survive in conditions that neither alone could.
Lichens (cont’d)
 Lichens play an important role in the process of soil
formation.
 They penetrate rocks and break the rock particles into
soil.
 Some nitrogen-fixing lichens add nitrogen to the
newly forming soil.
 Many lichens are adapted to withstand extremely cold
temperatures and can endure extreme desiccation
(drying out), most are extremely fragile to air
pollution.
Lichens (cont’d)
 Thallus – body of a lichen
-Thallus lacks flowers, stems, roots, and leaves.
 Ascomycotes – fungi that form the body of almost all
lichens and produce asci in ascocarps.
Lichens (cont’d)
 Crustose – Flat and tightly attachd to the substrate.
Most commonly found on rocks.
 Fruticose – Seem to be branched and extend upward
away from the substrate on which the lichen is
growing. It is sometimes commonly mistaken for
“moss” and are abundant on the north surfaces of
trees.
 Foliose – Has bodies divided into leaf-like thalli
(plural:thallus) that are different on the upper and
lower surfaces.
Photos of Lichen…
Crustose
Fruticose
Foliose
Identification Practice…
Name the Domain
Domain Bacteria
What division does cyanobacteria
belong to?
Division Cyanophyta
Are these multi-cellular or unicellular organisms?
Unicellular or colonial
Prokaryotic or Eukaryotic?
Prokaryotic
Identify an example of each of the
three cell types in this typical
cyanobacteria chain
Vegetative cells, heterocysts, and
spores
Are cyanobacteria autotrophic or
heterotrophic?
Autotrophic
What type of lichen is this?
Fruticose
Name the other 2 types of lichen
growth forms
Crustose & Foliose
Name one beneficial result of
lichen
Soil formation