Taxonomy Unit Tests PDF

Taxonomy unit test Taxonomy names groups and organisms according to their evolutionary history and characteristics. A taxon is a group of organisms in a classification system. Binomial nomenclature (a two-part scientific naming system that uses Latin) -​ Developed by Carolus Linnaeus -​ Two...

Taxonomy unit test Taxonomy names groups and organisms according to their evolutionary history and characteristics. A taxon is a group of organisms in a classification system. Binomial nomenclature (a two-part scientific naming system that uses Latin) -​ Developed by Carolus Linnaeus -​ Two parts are the genus name and the species descriptor (Binomial, nomenclature) Genus (name is always capitalized) -​ Includes one or more similar species -​ These species are generally thought to be related ​ Species descriptor (always capitalized) -​ The second part of a scientific name -​ It always follows the genus name and is never written alone -​ Binomial nomenclature offers less confusion, it is the same name everywhere you go, and much easier than a ten-word name under the old polynomial system -​ Scientific names help scientists communicate, many species have very similar or common names Carolus Linnaeus -​ A Swedish biologist who developed binomial nomenclature -​ He developed a hierarchy for classifying organisms and it is the basis for modern Taxonomy -​ He is deemed as the father of modern taxonomy Linnaeus’ classification system (King Phillip Came Over For Grandma’s Soup) -​ The seven levels of classification are Kingdom (Animalia), Phylum (Chordata), Class (Mammalia), Order (Carnivora), Family (Canidae), Genus (Canis), and Species (Canis lupus). -​ These were divided into two kingdoms, animals and plants (at that time fungi and algae were considered to be plants) Dichotomous keys -​ A system of branching out two-part statements used to justify organisms or objects -​ They provide an easy method of identification between different species How does it work? -​ at each choice of the process the user must make two choices and eventually through multiple choices, it leads to the classification of an organism on a taxonomic level -​ before scientists construct a key, they have to agree on features that distinguish a species Phylogeny/cladogram (systematics) -​ Systematics organizes the diversity of organisms into a phylogenetic tree Phylogenetic tree -​ Shows the evolutionary relationships between different organisms -​ It represents a hypothesis that is based on lines of evidence such as fossil record, morphology, embryological patterns of development, chromosomes, and macromolecules Cladistics -​ A system of taxonomy that constructs phylogenies by inferring relationships based on similarities, a common method to make evolutionary trees -​ Determines the sequence in which different organisms evolved -​ Focuses on a unique set of characteristics found in certain organisms called derived traits/characters -​ Biologists then use these traits to show the sequence in which these organisms evolved using a cladogram -​ The key cladistics is identifying traits that differ among an organism being studied that can be attributed to a common ancestor How does it work? -​ A clade is a group of species that share a common ancestor -​ Each species in the clade has a trait that has changed over time and shares some traits with the ancestor Derived Characters: traits shared in different degrees by clade members -​ more closely related species share more derived characters and are represented on a cladogram with hash marks Evolutionary Clues for Inferring Relations -​ The fossil record often provides clues, however, some fossil records are incomplete -​ Morphology can be used to compare organisms, homologous features are important as well. Is important to realize that the more homologous features an organism shares, the more closely related they are to each other -​ Embryological development provides evidence of phylogenetic relationships And provides a means of testing hypotheses about relations -​ Macromolecule comparisons using DNA, RNA, and other proteins help for a “molecular clock” -​ Scientists compare amino acid sequences for homologous protein molecules of different species -​ The number of amino acid differences provides a clue on how long ago two species diverged from sharing a common evolutionary ancestor Viruses -​ A small infectious particle containing genetic material containing DNA and RNA within a protein capsule they are surrounded by a capsid -​ They are hard to classify -​ Have no cytoplasm, and they cannot reproduce on their own, they need a host cell -​ They do not produce any energy Classification/Types (disease-causing viruses) DNA Viruses -​ Hepadnavirus: Hepatitis B -​ Herpesvirus: cold sores, genital herpes, chicken pox -​ Adenovirus: respiratory infections, tumours RNA Viruses -​ Paramyxovirus: measles, mumps, pneumonia, polio, common cold -​ Retrovirus: HIV/AIDS  -​ Rhabdovirus: rabies Bacteriophage: Viruses that infect bacteria cells Classification/ Phylogeny Viruses are not classified as living things like bacteria, they are classified as non-living because they do not have the same key characteristics as living cells. However, they can reproduce *not on their own*. -​ Viruses are classified by shape, size, and type of genetic material Origin of Viruses -​ Is still left as a hypothesis, however, they are believed to have originated as small infectious cells that have overtime lost their cytoplasm and ability to reproduce -​ Fragments of DNA/RNA molecules separated from living cells -​ They may have existed before the first cells and led to all forms of life Lytic/Lysogenic Cycle - Virus Reproduction Why does this happen? -​ Since viruses do not carry out the same functions as living cells do they become active when their genetic material has entered and taken control of a living cell -​ The process in which a virus infects a host cell, replicates, and destroys the host cell is called the infectious cycle this is an example using Lysis and Lysogeny Lysis (when the virus becomes active) -​ The rupturing of the cell, which can occur when the newly made viruses are released from a host cell Lysogeny (when the virus is in a holding place and it does not. Go into the infectious -​ A state of dormancy when the viral DNA remains within a host cell’s chromosome for many cell generations ex. When herpes is stored in someone's lip for some time because the virus is not active yet Lysogenic Cycle 1.​ First, the viral DNA binds to the surface of the host cell and inserts DNA into the host cell's cytoplasm 2.​ The cell then forms a loop and it may either go through the lytic or lysogenic cycle 3.​ In the lysogenic cycle, the viral DNA gets inserted into the bacterial chromosomes 4.​ *Replication* Each time the bacterium divides, the viral DNA is replicated along with the bacterial DNA 5.​ his cycle can go on for a very long time until the virus becomes active Lytic Cycle 1.​ *Activation and separation* When the viral DNA becomes active, it separates from the bacteria/host cells chromosomes and then it enters into the lytic cycle 2.​ In the lytic cycle, the viral DNA instructs the cell to create and make a new viral DNA and capsids, it also instructs the cell to make more viruses 3.​ Then Lysis occurs when the host cell bursts releasing 100-200 lysis and dies (lysis is when the virus becomes active and the cell ruptures) 4.​ Sometimes lysis occurs immediately after the host cell becomes infected Definitions of the Lytic and Lysogenic Cycles Attachment: a binding between viral capsid proteins and receptors on the host cellular surface, this determines the host range of the virus. Penetration: follows attachment, virions enter the host cell through receptor-mediated endocytosis Uncoating: a process in which the viral capsid is removed Replication: of viruses involves the multiplication of the genome Assembly: following the structure-mediated self-assembly of the virus particles, some modification of proteins occurs Release: viruses being released from the host cell by lysis Benefits of Viruses -​ Used to deliver drugs to target cells -​ Used to insert a new gene copy to replace a defective one -​ Use to insert a gene taken from one organism to place into a different organism (genetically modified organism) -​ Help with vaccines Vaccines -​ Contain a weakened form of a virus, *not enough to be dangerous or cause an infection* -​ This exposes the immune system to the virus so it can learn how to combat the virus -​ Not all viruses can be prevented by vaccines but serious diseases have been eradicated because of the use of vaccines Drawbacks ​ Viroids -​ Small infectious pieces of RNA -​ No capsid -​ Plant pathogens -​ killed 1 million coconut palms in the Philippines ​ Prions -​ Proteinaceous infectious particles -​ Abnormal proteins in the brains of infected animals -​ If eaten, prions enter the bloodstream and enter the second organism's brain -​ Prions interact with normal proteins in the brain and then alter them which in turn makes the brain look spongy Prion diseases Creutfeldt-Jakob disease: symptoms include dementia, paralysis, wasting and eventually death, this typically comes. From eating an animal affected by this ex. Eating sheep brain There is also Mad cow disease and Chronic wasting disease Bacteria Characteristics/Classifications of different types of bacteria Proteobacteria -​ Some photosynthetic but use a form of photosynthesis that differs from plants -​ Ancestors of mitochondria -​ Nitrogen-fixing -​ Responsible for gonorrhea, plague, dysentery, and some ulcers Green bacteria -​ Uses a form of photosynthesis that differs from plants, found in saltwater -​ Live in sulphur-rich environments  -​ Belong to the phylum chlorosis and are strictly anaerobic photoautotrophs Cyanobacteria (blue-green algae) -​ Use a form of photosynthesis like plants -​ Ancestors of chloroplasts -​ Found in all types of water -​ Play major roles as producers and nitrogen fixers in aquatic ecosystems -​ Form symbiotic relationships with fungi Gram-positive bacteria -​ Cause many diseases: anthrax, strep throat, bacteria pneumonia, meningitis -​ Used in making yogurt -​ can be classified through a staining method -​ Some have no cell wall -​ One type of them is the smallest- mycoplasmas Spirochetes -​ Their spiral-shaped flagellum is embedded in their cytoplasm -​ found in a liquid environment -​ The move in a cocksure motion and causes syphilis and Lyme disease -​ Symbiotic Relationship to Termite Intestines Digest Wood Fire Chlamydias -​ All are parasites that live within other cells -​ Cause chlamydia and trachoma (blindness in humans) Common Characteristics -​ A bacteria’s chromosome is a single loop of DNA, which is found in the nucleoid -​ Ribosomes are scattered throughout the cytoplasm -​ Bacteria also have more flagella for movement (they look like hairs) -​ Many bacteria have one or more plasmids in their cytoplasm -​ A plasmid is a small loop of DNA often found in prokaryotic cells -​ Some bacteria are surrounded by a Sticky capsule -​ A capsule is an outer layer of the cell that protects the cell There are Three Common Shapes of Bacteria: Coccus: a round bacterial cell Bacillus: a rod-shaped bacteria cell Spirillum: a spiral or cork-screw-shaped bacteria cell Archaebacteria Methanogens -​ live in low-oxygen environments: sediments of swamps, lakes lagoons -​ Has the digestive tract of some mammals (including humans) -​ Generate energy by converting chemical compounds into methane gas Halophiles -​ Live in environments like the Dead Sea, they love salt -​ Are aerobic and get most of their energy through organic food molecules and some use light as an energy source Extreme Thermophiles -​ Live in hot environments like hot springs  -​ Their optimal temperature range for growth is 70-95 degrees c Psychrophiles -​ Live in the Antarctic and trick oceans and love the cold -​ Their optimal temperature range for growth is -10-20 degrees Celsius Reproduction -​ Prokaryotes reproduce asexually -​ A parent cell divides through binary fission (Organism separates into two) and produces two identical daughters of bacteria -​ Each daughter receives an exact copy of the parent cell’s DNA -​ Bacteria mutate often because they reproduce quickly and mutate 100 times Bacteria can also gain new DNA through conjugation, transformation, and transduction Conjugation -​ A bacteria gives a copy of a plasmid to a nearby cell, introducing beneficial genes to the bacteria Replication 1.​ First, the cell replicates its DNA 2.​ The cytoplasmic membrane elongates separating DNA molecules 3.​ A cross forms, and it invaginates (separating it back within itself) 4.​ The wall forms completely 5.​ Then creates daughter cells Harmful Bacteria -​ Pathogens are infectious bacteria that are responsible for ear infections, cholera (vibrio cholerae bacteria), and tuberculosis (Mycobacterium tuberculosis) Diphtheria -​ Serious, contagious illness that affects breathing and is rare due to vaccination -​ Gives the appearance of the fleshy membrane in the throat Tetanus -​ Affects the nervous system, and causes muscle spasms -​ Rare due to immunization Bacterial Pneumonia -​ Infection in one or both of the lungs -​ Rod-shaped bacterial surrounded by a capsule (protects bacteria, harder to kill) Leprosy -​ Caused by the bacterium, Mycobacterium leprae -​ Unknown transmission, but most believe the bacterium passes through moisture excluded from the body Botulism -​ Rare, but serious paralytic illness caused by a nerve toxin, botulinum -​ Produced by the bacterium Clostridium botulinum -​ Botulin blocks nerve function and leads to respiratory paralysis Typhoid Fever -​ Acute illness associated with fever -​ Caused by salmonella -​ Bacteria deposited in water or food that can spread to other people Tuberculosis -​ Caused by the bacterium Mycobacterium tuberculosis -​ Affects the lungs but can also affect the nervous system and circulatory system Helpful Bacteria Cyanobacteria -​ produces oxygen in marine ecosystems using photosynthesis Nitrogen cycle -​ Nitrogen-fixing: atmospheric nitrogen to nitrates -​ Bacteria of decay: Decaying oxygen waste to ammonia -​ Nitrifying: Ammonia to nitrates/nitrites -​ Dentryifiying: nitrates to nitrogen gas Decomposers -​ Live in animal intestines Lactobacillus -​ Produces alcohol, dairy, chocolate, insulin, and antibiotics Antibiotic Resistance Prokaryotes and fungi produce antibiotic substances as a form of chemical warfare, the overuse of antibiotics can cause bacteria to adapt and become more resistant, making the antibiotic ineffective Stages of Antibiotic Resistance 1.​ Some bacteria have resistance to antibiotics and as they become exposed to antibiotics they prevail and reproduce 2.​ Then resistant bacteria make up more of the population 3.​ Which in turn, makes the antibiotics less effective, because they don’t reproduce at the same rapid speed that bacteria does Protista (Eukaryotes) -​ Microscopic and unicellular, process the same organelles as a cell -​ Some are heterotrophic and some are photosynthetic -​ There are three groups: plants (contain chlorophyll, ex. Euglena) -​ Animal-like protists (heterotrophs, ex. Paramecium) -​ Fungus-like protists (heterotrophs, ex. Slime mould) Animal-like Sarcodina -​ Free-living and parasitic -​ Motile pseudopods ex. Amoebae which ooze along through pseudopodia (false feet) engulfing as they go Mastigophora -​ The smallest of the Protozoa, have a whip-like projection called flagella poking out their cells (they use it to move) -​ Live in fresh and saltwater and are parasitic -​ They reproduce asexually and can form cysts Ciliophora -​ The largest Protozoa, covered in hair lie projections called cilia for movement -​ Produced asexually through binary fission and conjugation  -​ Found in every aquatic habitat eat two types of Protozoa and bacteria Sporozoa -​ Parasitic and non-motile -​ Spore like stage -​ An example is plasmodium which causes malaria Plant- Like Protist -​ Referred to as algae and produce much of the earth's oxygen -​ From the foundation of the earth's food chain and produce the earth's oxygen Euglenophyta (Euglenoids) -​ Live in freshwater, reproduce asexually, are autotrophs and heterotrophs because they make food from sunlight and ingest food from surrounding water -​ Ex. Euglena Chrysophyta (Golden algae) -​ Photosynthetic autotrophs -​ flagellates and have shell skeletons -​ Make up a large portion of the world's phytoplankton, which is the earth’s largest provider of oxygen Pyrrophyta (Fire algae) -​ Major component of marine phytoplankton -​ Two flagella and thick walls made of cellulose plates -​ Ex. dinoflagellates Rhodophyta (Red Seaweed) -​ Red seaweeds that live in fresh and seawater -​ Autotrophic and absorbs green, violet, and blue light waves -​ Found in warm or cold marine environments along coastlines in deeper water Phylum Phaeophyta (brown algae) -​ Brown algae found along cool saltwater along the rocky coast -​ chlorophyll and fucoxanthin -​ Giant kelp is the largest and most complex brown algae Phylum Chlorophyta (green algae) -​ Green algae found in freshwater, soils, and seas -​ Chlorophyll and carotene -​ Ex. Spirogyra Fungi Comparison between Plants and Fungi -​ They are like plants because they are stationary (sessile), multicellular, eukaryotes -​ They both grow in the ground -​ However, Fungi are not photosynthetic, don’t produce their food, have different reproductive methods and are more closely related to animals -​ Mycorrhiza is the relationship between plants and fungi when hyphae grow around the root cells of the plant Why are Fungi Important -​ Major decomposers of the earth  -​ Plants rely on fungi to help them obtain nutrients and without fungi, them, plant growth is reduced -​ Help create mushrooms, truffles, soy sauce -​ Valuable for being miracle drugs like antibiotic penicillin Types of Fungi Zygomycota (zygomycetes) -​ Commonly called mould (including bread and fruit mould) and are parasites of insects -​ Used commercially and grows rapidly -​ Their Hyphae have no cross (Aseptate) -​ Asexual reproduce Basidiomycota (Basidiomycetes) -​ They include mushrooms, puffballs, and bracket fungi -​ They are decomposers and have symbiotic relationships with plants -​ Seldom sexually reproduce Amastigomycota (Ascomycetes) -​ Many such as yeast are useful to humans -​ Cause serious plant diseases Chytridiomycota (Chytrids) -​ Only fungi with swimming spores -​ Most are saprophytes -​ They can be single-celled or multicellular Lichens -​ First organisms to begin the process of ecological succession and grow on bare rock -​ Some release chemicals to break down rock and soil Characteristics of Fungi Mycelium: a branched mass of hyphae Hyphae: A thin filament that makes up the body of a fungus Chitin: Complex chemical found in the walls of. Fungi and external coverings of insects and crustaceans -​ They reproduce asexually and sexually -​ They are classified by their sexually reproductive structure structures Spore: allows fungi to reproduce similar to the way that seeds allow plants to reproduce Hyphae: one continuous cell filled with nuclei and cytoplasm Symbionts: an organism closely associated with another organism, the larger organism is called a host ​ Leaf cutter ant (symbiont to fungi + Mycorrhiza is one too) -​ Live in tropical forests and gather leaves to bring to their colony -​ They clean and shew leaves to feed the fungi -​ The ants have colonies of bacteria growing on their bodies that kill fungi Plants Evolution of plants -​ Plants are thought to have evolved from a group of green algae (charophytes) millions of years ago  -​ The evidence that supports this is that plants and algae both contain chlorophyll, they contain pigments that are not found in other photosynthetic eukaryotes, and they both hold excess food as starch -​ Now there are about 270,000 different species of plants and they can be classified into 4 major groups: green algae, nonvascular plants (bryophytes), seedless vascular plants (pteridophytes), and gymnosperms Mosses -​ Small soft plants that are non-vascular and do not have flowers or seeds -​ Occasionally produce spore points for reproduction -​ Instead of roots, they have rhizoids (an anchor outgrowth that are like tiny hairs that keep moss in the ground to have nutrients) Ferns -​ Part of a group of vascular plants that thrive in woody vegetation -​ Reproduce by dropping spores on their leaves, where spores drop, ferns grow -​ hive from nutrients and water on the ground and make chlorophyll from sunlight Angiosperms vs Gymnosperms Gymnosperms -​ Flowerless plants that produce cones and seeds are. Known for their unprotected seeds as their seeds are openly exposed ex. Pinecones on Scots pine trees Angiosperms -​ Their seeds mature into a fruit and the fruit's job is to protect the seed it has inside to disperse them -​ The seeds can be protected by a flower Monocots Vs. Dicots Monocots -​ Makeup ¼ of all flowering plant species Ex. lilies, orchids, and grasses -​ One of the most important organisms on earth and creates foods like corn, rice, wheat and barley -​ They have features like seeds, root mass, flowers, leaf structures, pollen structures, etc Dicots -​ Part of angiosperms that have flower parts ex. Shrubs and trees -​ They have a pair of seeds in the embryo of the leaves -​ 50% of them are woody and have features like seeds, root mass, flowers, leaf structure, etc. Invertebrates Arthropoda (Arthropods, Insects): Segmented bodies, the outer layer contains chitin, have complete digestive, respiratory (gills internal airways), and excretory systems, live in aquatic and terrestrial systems Nematoda (Roundworms): unsegmented bodies with complete digestive tracts, parasites of other animals, live in soil and aquatic sediments Annelida (Segmented worms): segmented internal organs with complete digestive systems, many are marine, Gas exchange through skin or gills Mollusca (mollusks): have three unsegmented body parts (foot, visceral mass, and mantle) Rotifers: small aquatic animals, that live in freshwater, and use cilia to direct food. In their mouths, no respiratory or circulatory systems Platyhelminthes (flatworms): Flattened unsegmented worms, that have a digestive cavity with a single opening, and no circulatory or respiratory system, are parasites to other animals Cnidaria (stinging cells ex. Jellyfish): tentacles with stinging cells, one body opening, live in water Porifera (Sponges ex. Sea sponge): no body openings, no muscles or organs, live in water Echinodermata (spiny skinned): Bodies in 5 parts, covered in spikes or spines, external skeleton made of lime Vertebrates Agnathans (jawless fish Ex. Hagfish): have Gill slits but no paired appendages, marine and freshwater species, skeletons are made up of cartilage and have no jaws Chrondrichthytes (cartilaginous fishes ex. Sharks and rays): skeletons have cartilage, internal fertilization reproductive method, predators, thick-finned Actinopterygii (bony fishes, ex. Trout, bass, salmon): skeletons are bony, have a swim bladder, use external fertilization marine and freshwater species Amphibia (frogs, salamanders): aquatic larval stage with gills, and external fertilization, they breathe through their lungs and skin Reptilia (snakes, lizards, crocodiles): breathe with lungs, internal fertilization, and lay eggs, turtles are distantly related to this group Aves (ex.bird): most are capable of flight, have feathers, are warm-blooded, have larger brains, have acute vision, lay eggs, internal fertilization Mammalia: tetrapods have hair, nurse their young with milk, have internal fertilization, large brains and acute vision with smell, placental mammals are called humans Monotremes: animals that lay eggs Marsupials: animals that have pouches