General Botany
For LEVEL ONE
Plant Systematics
The Five Kingdoms
Prepared by
Dr. Momein H. El-Katatny
Department of Botany and Microbiology,
Faculty of Science, Minia University,
Egypt
Plant Science
• Botany
• Horticulture
• Agronomy
• Forestry
‫ﻋﻠﻢ ﺍﻟﻨﺒﺎﺕ‬
‫ﺍﻟﺒﺴﺎﺗﻴﻦ‬
‫ﺍﻟﻬﻨﺪﺳﺔ ﺍﻟﺰﺭﺍﻋﻴﺔ‬
‫ﺍﻟﻐﺎﺑﺎﺕ‬
Plant Science
• Taxonomy - Classification
• Anatomy - Structure
• Physiology - Function
• Morphology - Shape
Botany covers a wide range of scientific disciplines that study the
growth, reproduction, metabolism, diseases, and evolution of plant
life. It involves plants anatomy, physiology, ecology, taxonomy,
genetics.
The Five Kingdoms
Animal Bacteria
Fungi Plant Protist
5 Kingdoms
Some differences between Eukaryotic
and Prokaryotic cells
Eukaryotic cells
Prokaryotic cells
1. Have a nuclear envelope
1. Lack a nuclear envelope
2. Have two to hundreds of
chromosomes per cell: DNA is
double stranded
2. Generally is a circular, doublestranded piece of DNA plus
(usually) several to 40 plasmids .
3. Have membrane-bound organelles 3. Lack membrane-bound organelles
…
(eg. Plastids, mitochondria)
4. Have 80S ribosomes*
4. Have 70S ribosomes*
5. Have asexual reporoduction by
mitosis
5. Have asexual reproduction by
fission
6. Have sexual reproduction by fusion 6. Sexual reproduction unknown
* S is a Svedberg unit “measure particles settle to the bottom by centrifugation
Major Differences between prokaryotic and
eukaryotic micro-organisms
Prokaryotes
1. Nonmembrane bound
nucleiod region
2. DNA-one circular molecule
3.
one chromosome
3. Haploid-One copy of a gene
4. Plasma membrane does not
5.
contain sterols
5. Reproduction—simple binary
6.
fission
Eukaryotes
1. Membrane bound nucleus
containing DNA
2. DNA-linear molecules arranged
3.
to form several chromosomes
3. Diploid-Two copies of a gene
4. Plasma membrane contains
5.
sterols
5. Reproduction—meiosis and
6.
mitosis
6. Presence of membrane bound
7.
organelles such as chloroplasts
8.
and mitochondria
Classification of Living Things
Classification
(Classifying Organisms)
Why do Scientists Classify?
Imagine a grocery store…
How are they organized?
What would happen if they were not organized?
How is your life organized?
Almost 2 million kinds of organisms on Earth
Need to keep organized! (Easier to study!)
Classification
= process of grouping things based on their
similarities (according to characteristics)
When classifying organisms, scientists use
three main items to sort by:
1. cell structure
2. how the organism gets or makes its food
3. how the organism reproduces
History of
Classification
**Early Classification Systems**
Aristotle (4th century B.C.)
Aristotle, the Greek philosopher, came up with the first system of
classification. Aristotle classified organisms into only two
categories which were basically PLANTS and ANIMALS.
-observed animals
-watched appearance, behavior, movement
-fly, swim, and walk/crawl/run
-observed similarities and differences
-used differences to divide into smaller
subgroups
• Aristotle grouped animals according to the
way they moved
**Modern Classification Systems**
“John Ray”
was the first to use the term “species”
“Linnaeus”
The “father of modern taxonomy” was
Carolus Linnaeus (Carl von Linné)
1707-1778
Linnaeus
Carolus Linnaeus (1750s)
-used observations as basis of his system
-placed organisms based on observable features
-Living things were classified into : Vegetabilia
and animalia
Devised naming system for organisms:
Binomial Nomenclature
“Hog & Haeckel” 3 kingdoms
“Copeland” 4 kingdoms
“Whittaker” 5 kingdoms
“Woese” et al. (1977) 6 kingdoms
“Woese” et al. (1990) 3 Domains
History of Classification
Plantae
The Kingdoms of Life
Different approaches to classifying living organisms
The Five
Kingdoms
6 Kingdom Proposal
Archebacteria
EUbacteria
DNA of Archebacteria are
much different from other,
true bacteria
Most Archaea live in extreme
conditions
(very
hot,
acidic/basic, sulfurous, etc)
Three-domain system of classification
Two major branches of prokaryotic
evolution according to the
-molecular characteristics such as
ribosomal RNA sequences which
Unique for each
-No peptidoglycan in archaea
Carl Woese of the University of Illinois and his collaborators identified what
they believe to be two major branches of prokaryotic evolution. What was the
basis for dividing prokaryotes into two domains?
**Classification Now and
Today**
Species with similar evolutionary histories are classified more closely together.
-when organisms share a common ancestor, they share an evolutionary history
Levels of Classification
-based on contributions of both Aristotle and
Linnaeus
There are 7 levels of classification.
Remember the first letter of this sentence:
King Philip Came Over For Good Spaghetti.
LATIN is the language of classification for several reasons. First,
it was widely understood by 18th century scientists. Second, it
was known worldwide. Third, it was descriptive and the “root” of
many modern languages such as English, German, French, Italian,
etc.
7 Classification Levels of Living
things
Kingdom
broadest level
Phylum (Division)
Class
Order
Family
Genus
Species
most specific
Divisions
Life
Organisms are grouped into smaller and smaller groups all the way down
to their species
Binomial Nomenclature Linnaeus
What is a scientific name of an organism ?
Binomial Nomenclature
• Developed by Linnaeus
• Two-name system
• Each organism has a genus and a
species name
• First name (genus); second name
(species)
=2 part naming system
-uses Latin words
- Genus species
Felis concolor
- Genus is capitalized; species is NOT.
- If you can’t italicize, underline the
genus and species!
So that the Nomenclature :
• Latin
• Italic or underlined
• Genus species
For example:
Escherichia coli
A species is the most specific grouping and includes only organisms that
can interbreed with each other and produce fertile offspring ‫ﻭُﺗﻨﺘُﺞ ﻧﺴﻞ َ ﺧﺼَﺐ‬
Using the Classification System
Field guides help identify organisms.
-they highlight differences between similar
organisms (like trees)
Taxonomic Key (AKA Dichotomous Key)
-paired statements that describe the physical
characteristics of different organisms
Organisms are grouped into “taxa” based on
their similarities to each other
Taxonomic Key
•
•
•
•
•
•
•
•
•
•
1. Fruits occur singly ....................................................... Go to 3
1' Fruits occur in clusters of two or more ......................... Go to 2
2. Fruits are round ....................................................... Grapes
2' Fruits are elongate ................................................... Bananas
3. Thick skin that separates easily from flesh .............Oranges
3' Thin skin that adheres to flesh .............................. Go to 4
4. More than one seed per fruit ............................ Apples
4' One seed per fruit ............................................ Go to 5
5. Skin covered with velvety hairs .................... Peaches
5' Skin smooth, without hairs ........................... Plums
Dichotomous Keys
1a. Organism has 4 legs
Go to # 2
1b. Organism has more than 4 legs
Go to # 20
2a. Organism has a tail
Go to # 3
2b. Organism has no tail
Go to # 35
3a. Organism has stripes
Bengal Tiger
3b. Organism has no stripes
African Lion
Human Classification!!?
Domain:
Eukarya
Kingdom:
Animalia
Phylum:
Chordata
Class:
Mammalia
Order:
Primates
Family:
Hominidae
Genus: Homo
Species: sapien
Homo sapien
‫ﻫﻮ ﺍﻟﻜﺎﺋﻦ ﺍﻟﺤﻲ ﺍﻟﻮﺣﻴﺪ ﺍﻟﻤﺘﺒﻘﻲ ﻣﻦ ﺍﻹﻧﺴﺎﻥ ﺍﻟﻌﺎﻗﻞ‬
‫ﺍﻟﻬﻮﻣﻮ‪،‬‬
‫ﺑﺎﻹﻧﺠﻠﻴﺰﻳﺔ )‪: (Homo‬ﻫﻮ‬
‫ﺟﻨﺲ ﻳﻨﺪﺭﺝ ﺗﺤﺖ ﺍﻟﻔﺼﻴﻠﺔ‬
‫ﺳﻴﺔّ‪ ،‬ﻭﻳﺘﻔﺮﻉ ﻣﻨﻪ ﺍﻹﻧﺴﺎﻥ‬
‫ﺍﻷﻧﺎ ِ‬
‫ﺍﻟﺤﺪﻳﺚ ﺃﻭﺍﻷﻧﺴﺎﻥ ﺍﻟﻌﺎﻗﻞ‬
‫ﻭﺟﻨﺲ ﺍﻟﻬﻮﻣﻮ ﻳﻌﻨﻲ ﺍﻟﺠﻨﺲ‬
‫ﺍﻟﺒﺸﺮﻱ ﻷﻥ ﻛﻠﻤﺔ ﻫﻮﻣﻮ ﺗﻌﻨﻲ‬
‫ﺑﺸﺮ ﺑﺎﻟﻠﻐﺔ ﺍﻟﻼﺗﻴﻨﻴﺔ‬
‫ﺍﻹﻧﺴﺎﻥ ﺍﻟﺤﺎﺫﻕ )ﺍﻟﻤﺎﻫﺮ( ﻫﻮﻣﻮ ﻫﺎﺑﻴﻠﺲ‬
‫ﻧﻴﺎﻧﺪﺭﺗﺎﻝ( ﺑﺎﻟﻼﺗﻴﻨﻴﺔ )‪: Homo neanderthalensis‬ﺃﻭﺍﻹﻧﺴﺎﻥ ﺍﻟﺒﺪﺍﺋﻲ ﻫﻮ ﺃﺣﺪ ﺃﻧﻮﺍﻉ ﺟﻨﺲ ﻫﻮﻣﻮ‬
Viruses
Dea
d or
alive
HIV, Ebola
?
Prepared by
d
Dea
Dr. Momein H. El-Katatny
Department of Botany and Microbiology,
Faculty of Science, Minia University,
Egypt
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Introduction
What They Are
A virus is basically a tiny bundle of genetic material—
either DNA or RNA—carried in a shell called the viral
coat, or capsid, which is made up of bits of protein
called capsomeres. Some viruses have an additional
layer around this coat called an envelope. That's
basically all there is to viruses.
Introduction
•Toward the close of the nineteenth century, Iwanowski, a Russian plant
scientist, inoculated a small amount of sape of diseased tobacco plant into
a healthy tobacco plant. The healthy plant soon developed signs of a
disease.
•The healthy plants inoculated with the same sap which sterilized by
passing through the bacterial filter, showed the same results.
•This was a new discovery; The sap contains something other than
bacteria that causes the disease.
•The infective principle called virus has been isolated by Stanley (1935).
•At the boundary of life, between the macromolecules (which are not
alive) and the prokaryotic cells (which are), lie the viruses.
** Smallpox(‫ )ﺟﺪﺭﻯ‬, poliomyelitis (‫ )ﺷﻠﻞ ﺃﻃﻔﺎﻝ‬, measles (‫ )ﺣﺼﺒﺔ‬Viruses diseases for man
** Dog distemper, … Viruses disease for animals
** Mosaic diseases of plants (mottling of the leaves)
•Viruses do not belong to the above 5 kingdoms of life. they should
not be considered "living" organisms at all.
•They are much smaller and much less complex than cells (nanometer)
•They are macromolecular units composed of DNA or RNA surrounded
by an outer protein shell.
•They have no membrane-bound organelles, no ribosomes, no
cytoplasm, and no source of energy production of their own.
•They do not have metabolic reactions of living systems such as
cellular respiration, ATP-production, gas exchange, etc.
•However, they do reproduce, but at the expense of the host cell like
obligate parasites. (Can only reproduce inside a host cell!)
•In many cases the presence of a virus in a host cell may protect it
against infection with similar virus a phenomenon known as (cross
protection)
The Microbes
viruses
protozoa
bacteria
bacteriophage
algae
cyanobacteria
spirochaetes
fungi
Size of Microbes
Microbes vary in size ranging from
10 nm (nanometers) to 100 m
(micrometers) to the macroscopic.
Viruses in nm = 10-9 m (meter)
Bacteria in m = 10-6 m
Helminths in mm = 10-3 m
Viral structure
• Viruses are not cells.
• Basic structure:
– Protein coat (Capsid)
– Nucleic acid core (RNA or DNA)
– Lipoprotein coat
• (second coat – only in enveloped viruses)
The Complete assembly of infectious
particle is known as
“virion”
Types of viruses
According to the capsid shape
Polyhedral (Cubical)
Helical
Binal
Types of viruses
According to the Nucleic acid type
Viruses
DNA viruses
ss DNA
RNA viruses
dS DNA
Ss RNA
RNA - DNA viruses
Ds RNA
• DNA viruses – stable, do not mutate rapidly
– Single-stranded or double-stranded
– Smallpox, Hepatitis B
• RNA viruses – mutate rapidly, unstable
– Single-stranded or double-stranded
– HIV, Rhinovirus
Types of viruses
According to the host
Viruses
Plant viruses
RNA
Tobacco mosaic
diseases
Animal viruses
Bacterial viruses
RNA or DNA
Bacteriophages
DNA
Smallpox(‫ )ﺟﺪﺭﻯ‬,
poliomyelitis(‫ )ﺷﻠﻞ ﺃﻃﻔﺎﻝ‬,
measles(‫ )ﺣﺼﺒﺔ‬, Aids,
Rubella, Hepatitis
Types of viruses
According to the presence of envelope
Viruses
Naked viruses
Enveloped viruses
Complex viruses
Bacteriophage
Once inside the host the bacteriophage or
virus will either go into a Lytic Cycle -
destroying the host cell
during reproduction.
or
It will go into a
Lysogenic Cycle - a
parasitic type of
partnership with the cell
Can only reproduce inside a host
cell!
Phage life
cycle
Attachment
Release
Assembly
Attachment
Multiplication
Bacterial cell
Penetration
Bacterial cell
Penetration
Replication
Integration
1. Attachment 2. Penetration 3. Replication 4. Maturation (Assembly) 5. Release
The Lytic Cycle
Bacteriophage lytic life cycle
1. Attachment
The bacteriophage binds to receptors on the bacterial cell wall
2. Penetration
The bacteriophage injects its genome into the bacterium's cytoplasm
3. Early replication
The bacteriophage genome replicates and bacteriophage components begin to
be produced by way of the host bacterium's metabolic machinery
4. Late replication
The production of bacteriophage components and enzymes progresses
5. Maturation (Assembly)
The bacteriophage components assemble
6. Release
A bacteriophage-coded enzyme breaks down the peptidoglycan in the
bacterial cell wall causing osmotic lysis
1. Attachment 2. Penetration 3. Integration 4. Multiplication
The Lysogenic Cycle
Bacteriophage lysogenic life cycle
1. Attachment
The bacteriophage binds to receptors on the bacterial cell wall
2. Penetration
The bacteriophage injects its genome into the bacterium's cytoplasm
Bacteriophage lysogenic life cycle
3. Integration
Integration of phage DNA into bacterial chromosome
Bacteriophage lysogenic life cycle
4. Cell division (multiplication)
Integrated phage DNA replicates with the host chromosome
Lytic and lysogenic cycles
‫ﻭ ﺷﻜﺮﺍ ﻟﺤﺴﻦ ﺍﻻﺳﺘﻤﺎﻉ‬
End of our GAME for today …. See
you later