The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

A. Oxygen Demand

all eukaryotes require oxygen.

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

A. Oxygen Demand

all eukaryotes require oxygen.

bacteria show greater variability:

- obligate anaerobes - die in presence of O2

- aerotolerant - don't die, but don't use O2

- facultative aerobes - can use O2, but don't need it

- obligate aerobes - require O2 to live

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

A. Oxygen Demand

all eukaryotes require oxygen.

bacteria show greater variability:

- obligate anaerobes - die in presence of O2

- aerotolerant - don't die, but don't use O2

- facultative aerobes - can use O2, but don't need it

- obligate aerobes - require O2 to live

represents an interesting continuum, perhaps correlating with the presence of O2 in the atmosphere.

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

B. Nutritional Categories:

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

B. Nutritional Categories:

- chemolithotrophs: use inorganics (H2S, etc.) as electron donors for electron transport chains and use energy to fix carbon dioxide. Only done by bacteria.

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

B. Nutritional Categories:

- chemolithotrophs: use inorganics (H2S, etc.) as electron donors for electron transport chains and use energy to fix carbon dioxide. Only done by bacteria.

- photoheterotrophs: use light as source of energy, but harvest organics from environment. Only done by bacteria.

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

B. Nutritional Categories:

- chemolithotrophs: use inorganics (H2S, etc.) as electron donors for electron transport chains and use energy to fix carbon dioxide. Only done by bacteria.

- photoheterotrophs: use light as source of energy, but harvest organics from environment. Only done by bacteria.

- photoautotrophs: use light as source of energy, and use this energy to fix carbon dioxide. bacteria and some eukaryotes.

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

B. Nutritional Categories:

- chemolithotrophs: use inorganics (H2S, etc.) as electron donors for electron transport chains and use energy to fix carbon dioxide. Only done by bacteria.

- photoheterotrophs: use light as source of energy, but harvest organics from environment. Only done by bacteria.

- photoautotrophs: use light as source of energy, and use this energy to fix carbon dioxide. bacteria and some eukaryotes.

- chemoheterotrophs: get energy and carbon from organics they consume. bacteria and some eukaryotes.

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

B. Nutritional Categories:

- chemolithotrophs: use inorganics (H2S, etc.) as electron donors for electron transport chains and use energy to fix carbon dioxide. Only done by bacteria.

- photoheterotrophs: use light as source of energy, but harvest organics from environment. Only done by bacteria.

- photoautotrophs: use light as source of energy, and use this energy to fix carbon dioxide. bacteria and some eukaryotes.

- chemoheterotrophs: get energy and carbon from organics they consume. bacteria and some eukaryotes.

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

C. Their Ecological Importance

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

C. Their Ecological Importance

- major photosynthetic contributors (with protists and plants)

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

C. Their Ecological Importance

- major photosynthetic contributors (with protists and plants)

- the only organisms that fix nitrogen into biologically useful forms that can be absorbed by plants.

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

C. Their Ecological Importance

- major photosynthetic contributors (with protists and plants)

- the only organisms that fix nitrogen into biologically useful forms that can be absorbed by plants.

- primary decomposers (with fungi)

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

The key thing about bacteria is their metabolic diversity. Although they didn't radiate much morphologically (spheres, rod, spirals), they DID radiate metabolically. As a group, they are the most metabolically diverse group of organisms.

C. Their Ecological Importance

- major photosynthetic contributors (with protists and plants)

- the only organisms that fix nitrogen into biologically useful forms that can be absorbed by plants.

- primary decomposers (with fungi)

- pathogens

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

III. Domain Archaea and The Early Earth

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

III. Domain Archaea and The Early EarthThe three Archaean groups exploit extreme environments (like early Earth?):

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

III. Domain Archaea and The Early EarthThe two Archaean groups exploit extreme environments (like early Earth?):

Crenarchaeota:

'thermacidophiles' - reduce sulphur compounds in geothermal sulphur springs and geothermal vents.

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

III. Domain Archaea and The Early EarthThe two Archaean groups exploit extreme environments (like early Earth?):

Crenarchaeota:

'thermacidophiles' - reduce sulphur compounds in geothermal sulphur springs and geothermal vents.

Euryarchaeota:

'methanogens' - reduce CO2 and harvest small amounts of energy.

The Diversity of Life

I. An Overview

II. An Overview of 'The Bacteria'

III. Domain Archaea and The Early EarthThe two Archaean groups exploit extreme environments (like early Earth?):

Crenarchaeota:

'thermacidophiles' - oxidize sulphur compounds in geothermal sulphur springs and geothermal vents.

Euryarchaeota:

'methanogens' - reduce CO2 and harvest small amounts of energy.

'halophiles' - live in saline environments; some have a very primitive form of photosynthesis.

The Diversity of Life

IV. Domain Eukarya

A. Characteristics

- membrane bound nucleus

- organelles

- sexual reproduction

The Diversity of Life

IV. Domain Eukarya

B. Origins

infolding of membrane

The Diversity of Life

IV. Domain Eukarya

B. Origins

endosymbiosis - mitochondria and chloroplasts (Margulis - 1970's)

The Diversity of Life

IV. Domain Eukarya

B. Origins

endosymbiosis - mitochondria and chloroplasts (Margulis - 1970's)

The Diversity of Life

IV. Domain Eukarya

C. Phylogeny

The Diversity of Life

IV. Domain Eukarya

D. Diversity

The Diversity of Life

IV. Domain Eukarya

D. Diversity

The Diversity of Life

IV. Domain Eukarya

D. Diversity

The Diversity of Life

IV. Domain Eukarya

D. Diversity

The Diversity of Life

IV. Domain Eukarya

D. Diversity

The Diversity of Life

IV. Domain Eukarya

D. Diversity

The Diversity of Life

IV. Domain Eukarya

D. Diversity

- green alga

Same chlorophyll as plants

alternation of generation

genetic analysis confirms relatedness

The Diversity of Life

IV. Domain Eukarya

D. Diversity

- Choanoflagellates

The Diversity of Life

IV. Domain Eukarya

D. Diversity

E. Ecological Roles

- symbiotes – wood-digesting protists in insect guts

- parasites/disease - Plasmodium (Malaria)

- productivity – 25% of NPP by photosynthetic protists (diatoms and alga)

IV. Fungi

A. Overview

1. General Characteristics

IV. Fungi

A. Overview

1. General Characteristics

- multicellular eukaryotes

IV. Fungi

A. Overview

1. General Characteristics

- multicellular eukaryotes

- heterotrophic

IV. Fungi

A. Overview

1. General Characteristics

- multicellular eukaryotes

- heterotrophic

- absorptive nutrition:

excrete enzymes into environment and absorb the product of that digestion. They digest dead matter (decomposers) or live matter (pathogens), or may be symbiotes.

IV. Fungi

2. Classification

IV. Fungi

2. Classification

- Chytridiomycota

- Zygomycota

- Ascomycota

- Basidiomycota

Single celled members of these groups are all called “yeasts”. They are distinguished from protists based on a chitinous cell wall and absorptive (rather than phagocytic) nutrition.

IV. Fungi

3. General Biology

- The organism is composed of threadlike “hyphae”

IV. Fungi

3. General Biology- The organism is composed of threadlike “hyphae”- The hypha can be coenocytic (without divisions) or septate (with incomplete cell walls between)

IV. Fungi

3. General Biology- The organism is composed of threadlike “hyphae”- The hypha can be coenocytic (without divisions) or septate (with incomplete cell walls between)- These have a huge surface area/volume ratio for absorption.

IV. Fungi

3. General Biology- The organism is composed of threadlike “hyphae”- The hypha can be coenocytic (without divisions) or septate (with incomplete cell walls between)- These have a huge surface area/volume ratio for absorption.- The largest organisms known… 37 acres.

IV. Fungi

4. Ecological Roles

- decomposers: Fungi decompose lignin and cellulose, which most free-living bacteria can’t digest.

IV. Fungi

4. Ecological Roles

- decomposers: Fungi decompose lignin and cellulose, which most free-living bacteria can’t digest.

* antibiotics:

- Fungi and bacteria compete with one another for resources. They have both evolved chemical defenses that will kill or stop the reproduction of the other. The chemicals are antibiotics...and we use them to kill bacterial and fungal and protistan infections when they occur in the human body.

Penicillin - produced by the Penicillium bread mold.

Tetracyclins - produced by a bacteria.

IV. Fungi

4. Ecological Roles

- decomposers: Fungi decompose liginin and cellulose, which most free-living bacteria can’t digest.

* antibiotics

- mycorrhizae: fungal symbiotes of certain plants. The fungus increases the absorbance area of roots dramatically, and passes water and nutrients to the plant. The plant feeds the fungus with glucose.

- many of these fungi are more sensitive to pollutants and toxins that their host tree. For example, acid rain acidifies the soil and kills the mycorrhizae that feed spruce and fir trees. The trees die.

IV. Fungi

4. Ecological Roles

- decomposers: Fungi decompose liginin and cellulose, which most free-living bacteria can’t digest.

* antibiotics

- mycorrhizae: fungal symbiotes of certain plants. The fungus increases the absorbance area of roots dramatically, and passes water and nutrients to the plant. The plant feeds the fungus with glucose.

- lichens – symbiote with alga

IV. Fungi

4. Ecological Roles

- decomposers: Fungi decompose liginin and cellulose, which most free-living bacteria can’t digest.

* antibiotics

- mycorrhizae: fungal symbiotes of certain plants. The fungus increases the absorbance area of roots dramatically, and passes water and nutrients to the plant. The plant feeds the fungus with glucose.

- lichens – symbiote with alga

- pathogens – Athlete’s foot, ringworm,

yeast infections

- parasites – entomophagous fungi

IV. Fungi

D. Basidiomycetes

- bear puffballs or mushrooms as fruiting bodies

IV. Fungi

D. Basidiomycetes

- bear puffballs or mushrooms as fruiting bodies

IV. Fungi

D. Basidiomycetes

- bear puffballs or mushrooms as fruiting bodies

- haploid hyphae fuse in dikaryotic hyphae.

IV. Fungi

D. Basidiomycetes

- bear puffballs or mushrooms as fruiting bodies

- haploid hyphae fuse in dikaryotic hyphae.

- these dikaryotic hyphae form the fruiting structure.

IV. Fungi

D. Basidiomycetes

- bear puffballs or mushrooms as fruiting bodies

- haploid hyphae fuse in dikaryotic hyphae.

- these dikaryotic hyphae form the fruiting structure.

- at the tip of each hyphae, the basidium forms, in which meiosis occurs to produce new haploid spores.