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 o ? e v i l ra 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
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