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Taxonomy
BIO162
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Taxonomy: classifying and organizing life
species
Spaghetti
Genus
Good
Family
For
Order
Over
Class
Came
Phylum
Phillip
Kingdom
King
Domains (3)
• DOMAINS
1. Bacteria
2. Archea (Archbacteria)
3. Eukarya
1. Plantae
2. Animalia
3. Fungi (fungus)
4. Protista (algae & protozoa)
= Monera
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Kingdoms (5)
5 Kingdoms
1. Monera = Bacteria
2.
3.
4.
5.
Plantae = Plants
Animalia = Animals
Fungi = Fungi
Protista = Protists
Kingdoms (5)
5 Kingdoms
1. Monera = Bacteria
Prokaryotic
2.
3.
4.
5.
Eukaryotic
Plantae = Plants
Animalia = Animals
Fungi = Fungi
Protista = Protists
Cell Theory
Matthias Schleiden and Theodor
Schwann – proposed that all animal
and plant tissues were composed of
cells
Rudolf Virchow
Biogenesis – life can only arise from
preexisting life.
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The Two Major Categories of Cells
The countless cells on earth fall into
two categories
Prokaryotic cells
Eukaryotic cells
Prokaryotic and eukaryotic cells differ
in several respects.
Prokaryotic cell
Eukaryotic cell
Nucleoid region
Nucleus
Organelles
Figure 4.4
Prokaryotic cells
Are smaller than eukaryotic cells
Lack internal structures surrounded by
membranes (ie organelles)
Lack a nucleus.
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Prokaryotic
flagella
Nucleoid region (DNA)
Ribosomes
Plasma
membrane
Cell wall
Capsule
Pili
Figure 4.5
A Panoramic View of Eukaryotic Cells
Ribosomes
Cytoskeleton
Centriole
Lysosome
Flagellum
Not in most
plant cells
Plasma
membrane
Nucleus
Mitochondrion
Rough
endoplasmic
reticulum (ER)
Golgi
apparatus
Smooth
endoplasmic
reticulum (ER)
Figure 4.6A, p. 59
The Prokaryote Cell
Bacterial cell envelope
Cell membrane
Cell wall (composed of peptidoglycan)
Glycocalyx (slimy layer secreted outside cell wall)
Slime layer (not highly organized or attached to cell wall)
Capsule (highly organized and attached to cell wall)
Capsule (sometimes presents, identified by
negative stain)
Cytoplasm
Chromosome
Ribosomes
Cytoplasmic particles
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Cytoplasm
Medium found within the cell consisting of
Water
Enzymes
Oxygen
Waste
Proteins
Charbohydrates
Lipids
Cytoplasmic particles
ribosomes
Cell Wall
Gram Positive
Gram Negative
Gram Stain
Gram Positive
Gram Negative
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Chromosome (Bacterial Nucleoid)
Genetic material composed of a long,
single, super-coiled, circular DNA.
Duplicates self
Guides cell division
Direct cellular activity
Plasmids – extra-chromosomal DNA
not part of nucleoid, found in
cytoplasm.
Flagella
Flagella are protein
appendages that enable
bacteria to move:
Peritrichous bacteria –
flagella around perimeter
of bacteria
Lophotrichous bacteria –
tuft of flagella at 1 end
Amphitrichous bacteria –
flagella at both ends
Monotrichous bacteria –
single polar flagellum
Pili (Fimbriae)
Pili (pilus sing.) – hair
like structures found in
gram negative bacteria.
Not associated with
motility
Use to attach to surfaces
Transfer genetic material
from one bacterial cell to
another (sex pilus conjugation)
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Spores
Spores (Endospores) –
made by some bacteria
as means of survival.
Sporulation – process by
which spores are
formed.
Founded by John
Tyndall
Tyndallization – process
to kill sporulated bacteria
The Eukaryotic Cell
Protista – Protozoa and Algae
Fungi - Fungus
The Eukaryotic Cell
Cell Membrane
Cell Wall
Cytoplasm
Endoplamic Reticulum
Golgi Complex
Mictochondria
Cytoskeleton
Plastids
Lysosomes and Peroxisomes
Flagella and Cilia
Nucleus
Nuclear membrane
Chromosomes
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Plant Cells
Not in animal cells
Cytoskeleton
Mitochondrion
Central
vacuole
Nucleus
Cell wall
Rough endoplamsic
reticulum (ER)
Chloroplast
Ribosomes
Plasma
membrane
Smooth
endoplasmic
reticulum (ER)
Plasmodesmata
Golgi apparatus
Figure 4.6B, p. 59
Cell Membrane and Cell Wall
Cell Wall
Algae cell walls contain cellulose
Fungi cell walls contain chitin
Cell Membrane
Selective permeability
Mosaic model
Regulates passage of materials between
inside and outside of cell
Cytoplasm
Fluid matrix within cell
Organelles suspended in matrix
Cytoskeleton found in matrix and
maintains cell shape and is structural
component for movement
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Endoplasmic Reticulum and
Golgi Complex
Convoluted membrane system that is
interconnected.
Rough endoplasmic reticulum – contain
ribosomes for protein synthesis
Smooth endoplasmic reticulum
Golgi complex – completes protein
formation and packaging
Mitochondria and Plastids
Mitochondria – power plant of cells
where ATP is formed from cellular
respiration
Plastids – membrane bound structure
containing chloroplasts which is a site
of photosynthesis. (Light energy is
converted to chemical energy)
Flagella and Cilia
Flagella – structures used for
movement in some protozoa and algae
(i.e. flagellates)
Cilia – hair like structures found on
some protozoa (i.e. ciliates) also used
for movement
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Lysosomes and Peroxisomes
Lysosomes – originate at Golgi complex and
contain digestive enzymes to breakdown
foreign material.
Phagocytosis
autolysis
Peroxisomes – membrane bound vesicles
containing the enzyme catalase which
breaks down hydrogen peroxide into water
and oxygen
Nucleus
Membrane bound
Contains nucleoplasm
Chromosomes
DNA
RNA
Genome
Nucleolus – produces ribosomal
components
Classification
Carl Woese – developed a system of
classifying organisms based on rRNA
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References
http://www.bact.wisc.edu/themicrobial
world/structure.html
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