HIV and AIDS - SBI3U1 - DIVERSITY PDF

HIV and AIDS World Aids Day December 1, 2009  History of AIDS 1981 Large number of cases of Kaposi’s cancer in the US 1983 HIV was identified as the virus that causes AIDS  HIV http://www.youtube.com/watch?v=mzfnxC Esck4 ...

HIV and AIDS World Aids Day December 1, 2009  History of AIDS 1981 Large number of cases of Kaposi’s cancer in the US 1983 HIV was identified as the virus that causes AIDS  HIV http://www.youtube.com/watch?v=mzfnxC Esck4  HIV: A retrovirus Receptors: CD4 molecules Coreceptors: fusin, CCR5  Retroviruses (RNA Virus) Retroviruses have an enzyme that is capable of reverse transcribing their RNA into DNA. This viral DNA can then be integrated into the host cell’s genome. Retroviruses replicate with a high mutation rate. This increases it’s ability to evolve and survive. Steps: 1. Viral RNA enters the host cell along with the enzyme reverse transcriptase 2. Reverse transcriptase copies the viral RNA into DNA 3. The reverse transcribed viral DNA is integrated into the host cell’s genome http://www.youtube.com/watch?v=e S1GODinO8w (more descriptive) http://www.youtube.com/watch?v=dn1tNIr MPRk&feature=related (simple video clip)  Pathology of HIV Two major strains: HIV-1 and HIV-2 HIV primarily infects helper T cells in the immune system Helper T cells normally trigger other white blood cells to make antibodies Campbell Fig. 43.19 T-Cells T-cell is a type of white blood cell (leukocytes) The thymus is responsible for maturing the T-cells to fight infections. “T” stands for thymus  How HIV is spread By having unprotected sex with an infected person By sharing needles with an infected person HIV positive mothers can pass it on to their unborn children  Challenges with AIDS vaccines HIV is a retrovirus which integrates viral DNA into host DNA HIV has a high rate of mutations HIV attacks the body’s defense system  Modes of transmission Sexual intercourse Sharing needles Through breast milk From mother to child during childbirth  Thought question In the years following the discovery of the HIV pathogen, there was a sudden appearance of AIDS cases among hemophiliacs (people with inherited blood disorders). Why do you think this group was being infected with the disease? Bacteriophage Reproduction Lytic and Lysogenic Cycles The following information is taken from: http://student.ccbcmd.edu/courses/bio141/lecguide/unit3/index.html#charvir  Bacteriophage Structure More complex compared to other types of viruses Head = naked icosahedral capsid Tail = sheath with fibers at the end  Bacteriophage Life Cycle Overview Step 1 Step 2 Step 3 Step 4 Step 5 Step 6 Lytic = steps 1, 2, 5, 6 Lysogenic = steps 1, 2, 3, 4 (5 & 6 occur later)  The Lytic Cycle The following information is taken from: http://student.ccbcmd.edu/courses/bio141/lecguide/unit3/index.html#charvir Adsorption of a Bacteriophage to the Cell Wall of the Bacterium Protein on viral surface attaches to a specific receptor on the host cell surface. Penetration of the Viral Genome into the Cytoplasm of the Bacterium This step is also known as ‘Entry’. The viral genome (DNA or RNA) enters the host cell.  Viral Replication and Maturation Viral DNA is transcribed and then translated by the host cell. The protein parts produced are then assembled together while still inside the host cell.  Release of the Bacteriophages by Lysis of the Bacterium The fully formed viruses burst from the host cell by lysing it.  Lytic Cycle Summary 1. Adsorption: Attachment of virus to host cell surface 2. Entry/Penetration: Insertion of viral genome into the host cell 3. Replication: using viral genome to make viral RNA and proteins 4. Assembly of new virus components 5. Lysis of host cell & Release of virions  The Lysogenic Cycle The following information is taken from: http://student.ccbcmd.edu/courses/bio141/lecguide/unit3/index.html#charvir Adsorption of a Bacteriophage to the Cell Wall of the Bacterium Penetration of the Viral Genome into the Cytoplasm of the Bacterium  Formation of a Prophage Provirus = viral DNA integrated into host DNA Prophage = bacteriophage viral DNA integrated into host DNA The viral DNA is inserted into the host cell’s chromosome. As the host cell replicates it’s own DNA and divides itself during mitosis, the provirus/prophage is replicated along with it. The provirus/prophage lives dormant inside the host cell until...  Spontaneous Induction The separation of the provirus from the host chromosome. At this point the virus will complete the steps of the lytic cycle. Viral Replication and Maturation Release of the Bacteriophages by Lysis of the Bacterium Summary of the Entire Lysogenic Cycle 1. Adsorption 2. Entry 3. Integration: formation of provirus or prophage by inserting viral DNA into host genome 4. Spontaneous induction: release of viral DNA from host genome 5. Replication 6. Assembly 7. Lysis & Release Comparing the two Reproductive Strategies Lytic versus Lysogenic Lytic Cycle Lysogenic Cycle  Lysogenic Lytic Cycle Cycle  Advantages and Limits Lytic cycle Lysogenic cycle Replication of new viruses is Many more viruses can be fast made because the viral However, the host is also genome is passed onto immediately killed future generation of host preventing the viral genome cells from passing onto the next However, replication is generation of host cells takes longer because it is dependent on the host cell’s replication  Central Dogma DNA  RNA  Protein DNA = genetic information (original instructions) RNA = a copy of the genetic information (message) Protein = building blocks of life (workers) Transcription: DNA  RNA Translation: RNA  proteins http://www.youtube.com/watch?v=ztPkv7wc3yU&feature=r elated (transcription) http://www.youtube.com/watch?v=OtYz_3rkvPk&feature=rel ated http://www.youtube.com/watch?v=0248WyghCjc&feature=r elated (translation) The viral genome directs the host cell's metabolic machinery (ribosomes, tRNA, nutrients, energy, enzymes, etc.) to synthesize viral enzymes and viral parts.  DNA viruses Viral DNA can be integrated into the host cell genome so that it can then be transcribed and translated using the host cell’s machinery Steps: 1. Viral DNA integrate into host DNA 2. During transcription of host cell’s DNA, the viral DNA is transcribed along with it 3. Viral RNA is then translated into viral proteins which are the components that assemble to form the virion (new virus) Example: Herpes, Epstein-Barr, Mononucleosis  Herpes Herpes Simplex 1 and herpes simplex 2. The sores are sometimes accompanied by other symptoms such as: headache, fever, and other flu-like symptoms pain, itching, tingling, or tenderness around the genitals painful urination, swollen tender points in the groin and lower abdomen Chicken Pox varicella-zoster virus (VZV)  RNA viruses Viral RNA can be immediately translated with host cell’s machinery, skipping transcription. This occurs in the cell’s cytoplasm. Steps: 1. Ribosomes bind to all types of RNA, both host cell’s and viral RNA 2. Ribosomes translate RNA into protein 3. The viral proteins produced are the components that will be assembled to form the virion (new virus) 4. Example: HIV, Influenza, Tobacco Mosaic Virus  Retroviruses (RNA Virus) Retroviruses have an enzyme that is capable of reverse transcribing their RNA into DNA. This viral DNA can then be integrated into the host cell’s genome. Retroviruses replicate with a high mutation rate. This increases it’s ability to evolve and survive. Steps: 1. Viral RNA enters the host cell along with the enzyme reverse transcriptase 2. Reverse transcriptase copies the viral RNA into DNA 3. The reverse transcribed viral DNA is integrated into the host cell’s genome Example: HIV, Hepatitis Retroviruses (RNA Virus) Viruses  Definition a microscopic infective agent that consists of nucleic acid in a protein coat and is able to multiply only within the living cells of a host.  Criteria for classification 1. According to shape - Spherical: ex. Human immunodeficiency virus (HIV) - Cylindrical (helical): cylinder shape, ex. tobacco mosaic virus (TMV) - Polyhedral: resemble crystals, ex. polio Spherical - HIV  Cylindrical - Tobacco Mosaic Virus TMV is a virus that infects plants. Once inside the plant, it loses its protein coat exposing the nucleic acid and then it proceeds to reproduce. It multiplies once it is inside the living tissue but it can survive in a dormant state in dead tissue. It moves from plant to plant through mechanical transmission (ex. touch)  Polyhedral - Polio Virus Crystal shape – icosahedral (5 triangles meeting at a vertex)  Polio Virus enters through mouth Damages nervous system and results in paralysis Immunization can prevent infection  Polio Polio virus It is found in areas where water treatment and sanitation facilities are not properly maintained or non-existent. Although children under three years of age represent more than half of all cases polio can affect people of any age. Polio is a serious condition that causes paralysis in about 1% of those infected (paralytic polio). Nonparalytic polio causes symptoms that mimic the flu. Sore throat, fatigue, nausea, diarrhea, a fever, or vomiting. Most cases of nonparalytic polio clear up in a number of days, but a some people go on to develop meningitis, a condition in which the lining of the brain is infected. When a person develops paralytic polio, destroys nerves that control muscles. The infection may be fatal if the brain and respiratory organs become affected. Criteria for classification continued 2. According to genetic material: DNA virus, RNA virus 3. According to host range: only infect a certain type of cell within other organisms - Polio virus only infects human nerve and intestinal cells, - Bacteriophage (T4 virus) infects only bacteria - Mycophage infects only fungi Over 21 different types infect humans * natural reservoir: organisms that carry the virus but are not themselves affected by it (ex. shellfish for colera)  Characteristics of Viruses Living characteristics of viruses Reproduce at a fast rate, but only in living host cells Can mutate / evolve Contains genetic material (either DNA or RNA, but not both)  Nonliving characteristics of viruses Have no cellular structure (no organelles, no cytoplasm and no cell membranes) Infectious; dependent on a host cell for replication (intracellular parasite) Viral genome replicates by directing the synthesis of viral components using host cell machinery (e.g. use of nucleotides, amino acids, ribosomes, energy, enzymes) Do not have enzymes and therefore have no metabolic activity (energy) Lack systems required for metabolism  Animal DNA Virus Bacteriophage Viral Size Viruses are usually much smaller than bacteria and are submicroscopic. Most range in size from 5 to 300 nm. Thus viruses can infect even other microorganisms. Animal RNA Virus  Viral Structure A virus consists of these main parts: Genome (DNA/RNA) Genome Capsid (protein) Envelope (lipid) capsid  Viral Structure Genome (nucleic acid) Genetic material of the virus that codes for the synthesis of viral components and viral enzymes for replication Can be DNA or RNA but not both Can be single or double stranded Can be a circular or linear molecule Can be a single unit or segmented into parts  Viral Structure Capsid (core) A protein shell surrounding the genome. Protects and introduces the genome into host cells. Viruses that consist of only a genome surrounded by a capsid and are called nucleocapsid or naked viruses.  Viral Structure Envelope Most animal viruses have an envelope Composed of phospholipids and glycoprotein Usually derived from host cell membranes by a process called budding Electron Micrograph of HIV Budding from a T4-Lymphocyte Virus Obtaining Its Envelope from Host Cell Membrane by Budding ENDOCYTOSIS EXOCYTOSIS  Viral reproduction The Lytic Cycle and Lysogenic Cycle Protists Any organism not classified as a—plant, animal, fungus, or bacteria (prokaryote).  General Characteristics Some are unicellular while others are multicellular Eukaryotic Mainly undergo asexual reproduction (spores) Like moist surroundings  Importance They are at the bottom of the food chain = major food source for many organisms. Can be producers or primary consumers. Example: “red tide” due to increased number of red algae  toxins can kill fish and poison people who have eaten affected shellfish Also involved in symbiotic relationships- ex. red algae live in the bodies of corals (algae provide carbohydrates and corals provide shelters)  3 Groups of Protists 1. Plantlike protists : Algae aquatic and contain chloroplasts (carry out photosynthesis - autotrophs) size range from a single cell (ex. diatoms) to 60m in length (ex. green algae) some have flagella and able to swim (ex. euglenoids) some have cellulose cell walls  2. Animal-like protists: protozoa (“first animals”) Heterotrophs - feed on other organisms or dead matter (Example: amoeba and paramecium) Lack cell walls Pseudo Most are motile (some have flagella or cilia) (False Size range from 2 µm to 5 cm in diameter Many are parasitic ex. flagellates Trypanosoma causes African Sleeping Sickness - trypanosoma in salivary glands of tsetse flies  flies bite human and pass them  trypanosoma reproduce in human blood and spinal fluid  person becomes dizzy, falls into a coma, and dies  ex. plasmodium causes malaria Malaria—Plasmodium spread by mosquito  3. Fungi-like Protists: slime moulds and water moulds Heterotrophs - some are parasites on fish, insects, and plants (Harmful – ex. P. Infestans was a water mold which caused the Great Potato famine in Ireland) Decomposers - some feed on dead matter (Beneficial – recycles organic matter which results in providing nutrients for plants) Like cool, shady moist places Resemble protozoa and fungi Peanut butter – dog vomit mold Cherry cobler mold http://www.youtube.com/watch?v=IV bq2yQH52g Taxonomy Name the animal: Diversity in within species  What is taxonomy? The science of naming organisms and assigning them into groups called taxa (singular: taxon)  What is the biosphere? The part of the earth inhabited by living organisms  How does the biosphere relate to taxonomy? Taxonomy attempts to classify all organisms within the biosphere based on observed characteristics such as morphology, behaviour and sometimes even geographic location.  How does the biosphere relate to taxonomy? Taxonomy attempts to classify all organisms within the biosphere based on observed characteristics such as morphology, behaviour and sometimes even geographic location. What are some challenges they may face?  Approximately how many living organisms are there on earth? 30 to 100 million Only 1.75 million have been described so far  How did the invention of the microscope affect taxonomy? More organisms were discovered, therefore, more organisms to classify  Aristotle I categorized according to habitat: -water dwellers -land dwellers -air dwellers  St. Augustine I categorized based on a human centered view Useful, harmful, superfluous (not necessary) – Didn’t consider certain animals necessary in the environment  John Ray John Ray was born on November 29, 1627, in the village of Black Notley, Essex, England His father was a blacksmith and his mother was a healer and herbalist John Ray liked nature and especially plants. Coined the term Species – organisms similar in shape and structure and could reproduce with each other  Carl Linnaeus 1707-1778 Considered the father of taxonomy Grouped organisms according to their structural similarities and shared characteristics. - invented the Binomial nomenclature to classify organisms. Used genus and species based on the Latin names of the organisms -Latin was the language of scholars at the time. -Canis familiaris is the scientific name for a dog. (domestic dog)  Traditional taxonomical Ranks of Classification Kingdom Phylum Class Order Family Genus Species Memory aid (mnemonic device) –King Phillip called out for good soup  Classification System Brown Bear House cat Dog Killer whale Wolf Kingdom Animalia Animalia Animalia Animalia Animalia Phylum chordata chordata chordata chordata chordata Class mammalia mammalia mammalia mammalia mammalia Order carnivora carnivora carnivora cetacea carnivora Family ursidae felidae canidae delphinidae canidae Genus ursus felis canis orcinus canis Species arctos catus familiaris orca lupus  Classification System Brown Bear Animalia chordata mammalia carnivora ursidae ursus arctos  Classification System House cat Animalia chordata mammalia carnivora felidae felis catus  Classification System Dog Animalia chordata mammalia carnivora canidae canis familiaris  Classification System Killer whale Animalia chordata Mammalia cetacea Delphinidae orcinus orca  Classification System Wolf animalia Chordata Mammalia carnivora canidae Canis Lupus Classification System Classification System  Binomial Nomenclature A two word system of uniquely naming organisms according to their genus and species Generic name (genus) is capitalized Both words italicized – i.e. Homo sapien Binomial Nomenclature  Advantages of using the binomial nomenclature system 1. Universal scientific communication 2. Unique for every living thing 3. Show relationship between closely related organisms Dichotomous Key Di - two  Dichotomy Splitting of a whole into exactly two mutually exclusive parts (example: “good” versus “bad”)  Wacky people dichotomy Step 1 Step 5 If fish shape is long and skinny then go to step 2 If fish has spots, go to step 6 If fish shape is not long and skinny go to step 3 If fish does not have spots, go to step 7 Step 2 Step 6 If fish has pointed fins, it is a trumpet fish If fish has chin whiskers, it is a spotted goat fish If fish has smooth fins, it is a spotted moray eel If fish does not have chin whiskers, it is a band-tail puffer Step 3 Step 7 If fish has both eyes on top of head, go to step 4 If fish has stripes, go to step 8 If fish has eye on each side of the head, go to step 5 If fish does not have stripes, it is a glassy sweeper Step 4 Step 8 If fish has long whip like tail, it is a spotted eagle ray If fish has a V-shaped tail, it is a squirrel fish If fish short blunt tail, it is a peacock flounder If fish has a blunt tail, it is a glass eye snapper  What is a dichotomous key used for? Used to help place organisms into an appropriate classification group  What are the 2 conditions for a properly written dichotomous key? 2 choices for each characteristic Unique ending for each individual item (think of the fish example)  Two ways a dichotomous key can be represented? Diagrammatically (tree/flow chart) With words How does a dichotomous key relate to the 7 taxa and binomial nomenclature? Characteristics that define the choices (dichotomy) are often based on the characteristics that subdivide each taxa (e.g. vertebrate vs. invertebrate) A true key ends with a scientific name of the organism using the binomial nomenclature system Similar structures are referred to as homologous structures Classification System  Classification System Where you live, from broad to specific: - The Universe - The Milky Way Galaxy - The Solar System - Planet Earth - North American Continent - Canada - Ontario - Toronto - North York - Your address Classification of Plants  Plants Similarities between green Aquatic Plants algae and land plants: Ex. green algae A) have chlorophylls a and b B) cellulose cell walls C) store food energy in the form of starch (rather than glycogen)  Plants to Land (400MYA) Adaptations that needed to be evolved before plants could live on land: A) protection from drying out B) system of transport from outside environment to cells in the body of plant C) system to support the body of plant  Adaptation to Land 3 organs that developed to adapt to life on land: A) roots: penetrate soil to anchor plant; reach water source B) leaves: greater surface area for photosynthesis C) stems: rigid tissue to raise and support leaves  Land plants: non-vascular vs. vascular Vascular plants appeared 360MYA Vascular tissue : A system of tubes that carry water and dissolved nutrients through a plant Made up of xylem and phloem  Land plants: non-vascular vs. vascular Non-vascular (bryophytes) Vascular (tracheophytes) No vascular (transport) tissue has vascular tissue to Have root-like, stem-like and transport water and leaf-like structures (poorly nutrients developed roots, leaves and Have true roots, stems and stems) leaves Grow taller, larger Grow short, small 1) seedless (spore producing) ex. mosses, liverworts, Ex. ferns hornworts 2) seed producing Ex. conifers, flowering plants  Non-Vascular vs. Vascular Advantage of vascular plants? - can live in drier environment - can grow larger (water and nutrients can reach far with the vascular tissue) Non-vascular plants live in moist environment and have smaller sizes.  Non-vascular (bryophytes) Mosses Liverworts Hornworts  Vascular (tracheophytes) 1) Seedless (spore-producing) ex. ferns  Advantages of having seeds A) food storage B) tough waterproof coat – protection against harsh conditions C) remain dormant- survive exposure to harsh conditions D) sexual reproduction without needing water Gymnosperm- “naked seed” ex. ginkgoes, conifers Angiosperms-flowering plants  Seed Structure Gymnosperms vs. Angiosperms Means “naked seed” Means “seed in a vessel” Seeds that are exposed Seed = embryo to the environment +nutrient storage+ coat (often as cones) Seeds are not exposed Thin cover of protection to the environment (drought, fire…) Seed protected with body of fruit  Examples Gymnosperms vs. Angiosperms Conifers: produce cones in the Flowering plants spring and summer Also grass and herbs Male vs. female cones (in clusters) (scattered, hidden seeds)  Number of species Gymnosperms vs. Angiosperms Smaller in number Larger in number Approx. 1000 species Approx. 250 000 species  2 groups Flowering Plants (Angiosperms) Monocotyledons Dicotyledons roots, stems, leaves vascular tissues (transport) flowers, fruits (contain seeds)  Two peanut seeds Two apple seeds in the hard ovary vs in the fleshy fruit  Monocotyledons and Dicotyledons Cotyledon: the structure in a plant’s seed that stores carbohydrates for the seedling It’s known as “seed leaf” because the plant’s first leaf develops from it. ex) onion- single leaf →monocot alfalfa- two leaves → dicot Monocotyledons Parallel veins Dicotyledons Veins in network Structure Monocots Dicots Number of 1 2 cotyledons Number of Multiples of 3 Multiples of 4 flower petals or 5 Number of Fewer More species Examples Tulip, lily, corn, Rose, maple onion, grass, tree, carrot, rice, banana potatoes, beans Root structure Structure Monocots Dicots Root cross- Vascular bundles xylem in the center of section are arranged in a the root (with an X ring shape) and phloem outside the xylem. Root system Fibrous roots- Tap roots – one large many thin roots vertical root with smaller branches Stem Vascular bundles Vascular bundles are cross- are scattered arranged in a ring section Tissue Herbaceous –soft Woody- tough, rigid & flesh stems Only about 10% are woody THE SIX KINGDOMS  THE SIX KINGDOMS All living things Eukaryote Virus????? Prokaryote Animalia Bacteria Archaebacteria Plantae Monera Archaea Eubacteria Fungi Protista Comparing Prokaryotic and Eukaryotic Cells Comparing Prokaryotic and Eukaryotic Cells a) Prokaryotes do not have a nucleus b) Prokaryotes do not have membrane-bound organelles Comparing Prokaryotic and Eukaryotic Cells PROKARYOTE EUKARYOTE Meaning of name Pro means before Eu means after Karyon means Karyon means nucleus nucleus Evolution of first cells 3.5 billion years ago 1.5 billion years ago (older type of cell) Size of cells Smaller (1-10 μm) Larger (100-1000 μm) Uni-/multicellular Unicellular (less Unicellular/Multicellular complex) (more complex) Organelles Absent Present Location of genetic Nucleoid region Nucleus information DNA structure Circular (usually one Not circular (more than chromosome) one chromosome) Reproductive strategy Asexual/Sexual Asexual/Sexual Comparing Fungi and Plant Cells a) Fungal cells do not have chloroplasts (plants do) b) Fungal cells are heterotrophic (plants are autotrophic) c) Fungal cells have rigid cell walls made from chitin (plants have walls made of cellulose)  Comparing Fungi and Plant Cells Fungal cells often fuse together, making it hard to locate one discrete cell in the organism  Protists There are many different types of protists  All cells have in common: 1) All cells have cytoplasm 2) All cells have genetic material 3) All cells have a membrane Size: Viruses Viruses Vs. Cells are much smaller than cells Life cycle: How can something without life have a life Metabolism: cycle? Viruses do not metabolize (no cytoplasm) Genetic material: Viruses contain RNA Organelles: or DNA enclosed by Viruses do not protein, not a have organelles membrane  Viruses Viruses are not considered “living” when outside a host cell The general name for a virus in this state is “virion” They are not considered living in this state because they are inactive and cannot reproduce Sauerkraut explosion prompts quarantine Last Updated: Saturday, September 11, 2010 | 2:58 PM PT The Canadian Press Twenty-four students and four staff members at a central B.C. high school were briefly quarantined after a can of sauerkraut exploded Friday in a food science class. The fire department, a hazardous materials unit and RCMP were called to Kelly Road Secondary School in Prince George at about 2 p.m. PT. RCMP Const. Lesley Smith said school officials were concerned about a possible botulism outbreak after the contents of a years-old can of pickled cabbage splattered on students. Officials later determined there was no cause for alarm. The students briefly returned to their classes, then were dismissed early. Clostridium botulinum Botulinum toxin  leads to paralysis  Comparing the Six Kingdoms Classification Prokaryote Eukaryote Kingdoms Archaea Bacteria Protista Fungi Plantae Animalia Body Form unicellular unicellular Unicellular/ Unicellular/ Multicellular Multicellular multicellular multicellula (unicellular/ r multicellular) Mitochondria Absent Absent Present Present Present Present (absent/ present) Cell Wall Present Present Present in Present Present Absent (absent/ present) (different from (peptidoglyca some (cellulose) (chitin) bacterial CW) n) Nutrition Absorption, Absorption, Absorption, Absorptio Photosynthes Ingestion (absorption, photosynthesi photosynthes photosynth n is photosynthesis, s, is, esis, chemosynthesis, chemosynthes chemosynthe ingestion ingestion) is sis Nervous Absent Absent Absent Absent Absent Present System (absent/ present) Motility Present in Present in Present in Absent Absent present (absent/ present) some some some  Comparing the Six Kingdoms Classification Prokaryote Kingdoms Archaea Bacteria Body Form unicellular unicellular (unicellular/ multicellular) Mitochondria (absent/ Absent Absent present) Cell Wall (absent/ Present (different from Present present) bacterial CW) (peptidoglycan) Nutrition Absorption, Absorption, (absorption, photosynthesis, photosynthesis, photosynthesis, chemosynthesis chemosynthesis chemosynthesis, ingestion) Nervous System Absent Absent (absent/ present) Motility Present in some Present in some  Comparing the Six Kingdoms Classification Eukaryote Kingdoms Protista Fungi Plantae Animalia Body Form Unicellular/ Unicellular/ Muticellular Multicellular (unicellular/ muticellular muticellular multicellular) Mitochondria Present Present Present Present (absent/ present) Cell Wall (absent/ Present in some Present Present Absent present) (chitin) (cellulose) Nutrition Absorption, Absorption Photosynthe Ingestion (absorption, photosynthesis, sis photosynthesis, chemosynthesis, ingestion ingestion) Nervous System Absent Absent Absent Present (absent/ present) Motility Present in some Absent Absent present (absent/ present) Kingdom Archaea Scientists believe that Archaea are the first living things on Earth because… They thrive in extreme conditions that mimic the Earth’s early atmosphere Kingdom Archaea Examples of extreme conditions: boiling/acidic water hydrothermal vents super-salty pools Antarctic permanent ice These are conditions that would normally kill other creatures, thus Archaea are classified by the type of environment they thrive in. Kingdom Archaea Examples of extreme conditions: boiling/acidic water hydrothermal vents super-salty pools Antarctic permanent ice Three Groups of Archaea Thermoacidophiles Able to tolerate extreme temperature & acidity Example: volcanoes, hot springs Energy obtained from sulfur Halophiles Thrives in high salt environments Example: Dead Sea Energy obtained from organic food molecules and light Methanogens Lives in oxygen free environments Example: swamp, marsh, sewage Energy obtained by converting inorganic molecules leaving methane gas as a waste product  Kingdom Bacteria Beneficial Bacteria Nitrogen cycle: bacteria critical to soil fertility, converts ammonia to usable compounds: ammonia  nitrite  nitrate Certain bacteria makes foods edible: vinegar, butter, cheese, yogurt, and sour-dough bread Bacteria in Industry Bacteria used in sewage treatment, odor control, and septic tank maintenance: digests organic matter and waste  Bacteria in Disease Tuberculosis Lysteriosis Lyme disease Gonorrhea Meningitis Streptococcus mutans  tooth decay Clostridium botulinum  food poisoning Treponema pallidum  syphilis  Bacterial Classification Shape – 3 types (more details to follow) Cell Wall – 2 types (more details to follow) Energy Source – 2 types – Photosynthetic: obtain energy from light – Chemosynthetic: obtain energy from inorganic compounds Bacterial Shapes - general Cocci (singl. coccus) – round Resists drying Bacilli (bacillus) – rod-shaped Absorbs more nutrients due to greater surface area Spirilli (spirillum) – spiral-shaped Moves through fluids with the least resistance Bacterial Shapes i Bacterial Shapes Groupings Prefix diplo- Arranged in pairs Prefix staphylo- Arranged in clusters (like grapes) Prefix strepto- Arranged in chains Groupings  Practice Naming Bacteria A B C D E Answers: A. Staphylococci B. Streptococci C. Diplobacilli D. Streptobacilli E. Streptococci F G F. Diplospirilli G. Streptobacilli Diversity within shapes – getting more specific  Gram-positive 1884: Hans Grams discovered a method of classifying bacteria using Purple stain what is now named the “Gram Stain.” Thick protein layer Gram-negative A dye that highlights basic differences in the arrangements of Pink stain molecules in bacterial cell walls Thin protein layer Gram-negative bacilli from a pneumonia infected lung  Gram positive Gram negative Stains purple Stains pink Thick layer of Thin layer of peptidoglycan protein peptidoglycan protein Less resistance against More resistance against antibodies antibodies Stain cannot be easily Stain can be easily washed away washed away A C Gram-positive Staphylococcus aureus Gram-positive anthrax bacteria (bacilli) in cerebrospinal fluid sample. If present. (The other cells are white B blood cells). Mixture: gram-negative (pink) bacilli and gram-positive (purple) cocci Beneficial Bacteria Nitrogen cycle: bacteria critical to soil Antibiotics are extremely useful in curing diseases and saving lives Antibiotics kill bacteria by weakening its cell wall Some bacteria develop resistance to antibiotic and can therefore survive and reproduce. Therefore the overuse of antibiotics can cause bacteria to adapt and become resistant to usable compounds: ammonia  nitrite  nitrate Certain bacteria makes foods edible: vinegar, butter, cheese, yogurt, and sour-dough bread  (no mixing of genetic material between organisms) through… 1. Duplicate BINARY FISSION genetic material Binary = 2 Fission = division / split 2. Cell elongates A type of cell division where 2 genetically identical products of the same size are 3. Septum (wall) formed begins to form Occurs when conditions are favourable and 4. Cells separate constant (predictable). But why?…  (mixing of genetic material between organisms) through… Occurs when conditions begin to alter such that it’s less than ideal. What CONJUGATION advantage does this have?… 1. Cells linked by a bridged structure called the pili (pilus) 2. Genetic information passes through pili from one cell to another 3. Receiving cell undergoes binary fission  (mixing of genetic material between organisms) through… CONJUGATION Sex pilus (mixing of genetic material between organisms)  (no growth, dormancy) During unfavourable conditions, a bacteria enters a dormant phase to protect itself. It forms a tough outer covering to enclose its DNA. The resulting product looks like a seed and is called an endospore. When favourable conditions return, endospore loses its outer coat allowing the bacteria to grow again.  ADVANTAGE DISADVANTAGE ASEXUAL SEXUAL SPORE  ADVANTAGE DISADVANTAGE Conserves energy One parent ASEXUAL Very fast reproduction rate SEXUAL SPORE  ADVANTAGE DISADVANTAGE Conserves energy Rapid reproduction leads to One parent competition ASEXUAL Very fast reproduction rate Identical to parent: no diversity Higher risk for extinction SEXUAL SPORE  ADVANTAGE DISADVANTAGE Conserves energy Rapid reproduction leads to One parent competition ASEXUAL Very fast reproduction rate Identical to parent: no diversity Higher risk for extinction Genes can be manipulated Different from parents SEXUAL Genetic variation increases the likelihood of the species surviving in changing (or unfavourable) conditions SPORE  ADVANTAGE DISADVANTAGE Conserves energy Rapid reproduction leads to One parent competition ASEXUAL Very fast reproduction rate Identical to parent: no diversity Higher risk for extinction Genes can be manipulated Uses more energy Different from parents Requires two parents SEXUAL Genetic variation increases Slow the likelihood of the species surviving in changing (or unfavourable) conditions SPORE  ADVANTAGE DISADVANTAGE Conserves energy Rapid reproduction leads to One parent competition ASEXUAL Very fast reproduction rate Identical to parent: no diversity Higher risk for extinction Genes can be manipulated Uses more energy Different from parents Requires two parents SEXUAL Genetic variation increases Slow the likelihood of the species surviving in changing (or unfavourable) conditions Able to resist unfavourable conditions (e.g. extreme heat, SPORE cold, damaging chemicals, drying) Long life span  ADVANTAGE DISADVANTAGE Conserves energy Rapid reproduction leads to One parent competition ASEXUAL Very fast reproduction rate Identical to parent: no diversity Higher risk for extinction Genes can be manipulated Uses more energy Different from parents Requires two parents SEXUAL Genetic variation increases Slow the likelihood of the species surviving in changing (or unfavourable) conditions Able to resist unfavourable Slow process conditions (e.g. extreme heat, No growth during dormancy SPORE cold, damaging chemicals, drying) Long life span  Kingdom Fungi Mold Yeast Mushroom Mushroom: Specialized reproductive part of fungus Hyphae: network of fine filaments Septum: porous walls that divide the hyphae into cells Chitin: material that forms the cell wall of fungi Mycelium: loose, branching network of hyphae under the soil making up the main bulk of a fungus The septa of a hyphae is often porous (pictured below) -this allows cytoplasm to travel through it 1.Hyphae releases digestive 1 enzymes over its food 1 2. Molecules that are broken down outside the body then diffuse in 3. The more extensive the 2 mycelium, the greater the surface area for absorption  Symbiotic Relationships Mutualism Commensalism Parasitism  Symbiotic Relationships Mutualism +/+ Commensalism Parasitism  Symbiotic Relationships E. Coli in human intestine Mutualism E. Coli receive food / shelter +/+ Humans receive vitamins Commensalism Parasitism  Symbiotic Relationships E. Coli in human intestine Mutualism E. Coli receive food / shelter +/+ Humans receive vitamins Commensalism +/0 Parasitism  Symbiotic Relationships E. Coli in human intestine Mutualism E. Coli receive food / shelter +/+ Humans receive vitamins Barnacles on jaws of whale Commensalism Barnacles eat food filtered by +/0 whale. No effect on whale. Parasitism  Symbiotic Relationships E. Coli in human intestine Mutualism E. Coli receive food / shelter +/+ Humans receive vitamins Barnacles on jaws of whale Commensalism Barnacles eat food filtered by +/0 whale. No effect on whale. Parasitism +/-  Symbiotic Relationships E. Coli in human intestine Mutualism E. Coli receive food / shelter +/+ Humans receive vitamins Barnacles on jaws of whale Commensalism Barnacles eat food filtered by +/0 whale. No effect on whale. Many diseases: malaria, tetanus Parasitism Mistletoe grow on host trees. +/- Uses trees to obtain nutrients.  Symbiotic Relationships Mutualism  Symbiotic Relationships Commensalism  Symbiotic Relationships Parasitism Barnacles on whale Mistletoe on tree - ectocommensalism - ectoparasitism  Symbiotic Associations Ectosymbiosis Endosymbiosis  Symbiotic Associations One organism lives on the surface Ectosymbiosis another organism (e.g. barnacles on whales, mistletoe on trees) Endosymbiosis  Symbiotic Associations One organism lives on the surface Ectosymbiosis another organism (e.g. barnacles on whales, mistletoe on trees) One organism lives within the Endosymbiosis tissue of another organism (e.g. E. coli in humans, malaria, tetanus)