BROOKS BIODIVERSITY UNIT 1 EXAM | QUESTIONS & ANSWERS (VERIFIED) | LATEST UPDATE | GRADED A+

1 BROOKS BIODIVERSITY UNIT 1 EXAM | QUESTIONS & ANSWERS (VERIFIED) | LATEST UPDATE | GRADED A+ evolution Correct Answer: the concept that all given organisms are related to each other though common ancestry Have scientists proven that life exists? Correct Answer: No Big Bang Correct Answer: Theory of how the universe formed 16-18 billion years ago Symbiosis Correct Answer: the interaction between two different organisms living in close association "life coming together" Spontaneous Generation Correct Answer: Theory that life arose spontaneously from inanimate matter. Not a widely held belief among scientists 2 Biogenesis Hypothesis Correct Answer: Theory that living matter created by pre-existing living matter Haldane-Oparin Hypothesis Correct Answer: "Chemical Evolution" Life arose spontaneously from early atmospheric compounds. It was believed that the early atmosphere contained methane, ammonia, and water. When combined with energy sources, life arose. This is the original theory of how life arose, but is likely INCORRECT. Miller-Urey Experiment Correct Answer: Tested the Haldane-Oparin Hypothesis by conducting an experiment that simulated the conditions thought at the time to be present on earth, and tested for the occurrence of chemical origins of life. They took inorganic compounds and made organic compounds (mostly amino acids). DID NOT PROVE ANYTHING Panspermia Correct Answer: Hypothesis that organic molecules were brought to earth by meteorites/asteroids. Basically, life was seeded from outer space, and that life exists throughout the universe distributed by meteoroids, asteroids, comets, and planetoids. Modern Theory of How Life Arose 3 Correct Answer: (STILL NOT PROVEN, ONLY LIKELY) life arose spontaneously from simple molecules (CO, CO2, N2,H2 (very little because it was in little abundance), and H2O), then combined into larger, complex macromolecules such as proteins, carbohydrates, lipids, and nucleic acids. (NOT from methane, ammonia, and water as Haldane-Oparin hypothesized) Primordial Soup Hypothesis Correct Answer: Hypothesized that the first organisms were heterotrophs because they consumed the abundant food molecules present in the atmosphere The Cell Correct Answer: the basic form of an entity The Cell Theory Correct Answer: every life form (from bacteria to humans) is made up of/comes from cells Steps of the development of cells Correct Answer: 1. Spontaneous formation of simple molecules (Carbohydrates, lipids, proteins, and nucleic acids) 2. Formation of lipid bilayer, polymers, and Protien-RNA systems. 4 3. Lipid Bilayer forms selectively permeable barrier that contains an enclosed selfreplicating system. Closed system contains DNA, RNA, proteins, and enzymes. (VERY IMPORTANT!) 4. Abiotic (derived from non-living things) formation of protobiont (initial structures during the origin of life which can show at least one propery of life) using self-replicating molecules 5. Composition of anaerobic prokayotic cells, then followed by aerobic and photosynthetic prokaryotic cells 6. Single celled eukaryotic cells form and then evolve into multicellular organisms DNA vs RNA. Which came first? Correct Answer: Scientists believe RNA was first genetic material because RNA can also form ribozymes which catalyze reactions Unresolved Problems of the Modern Theory of How Life Arose Correct Answer: 1. Formation of large, complex organic molecules via dehydration or condensation bonds in an aquatic environment is a problem because of the concept of hydrolysis. Water actually breaks most things down. Since all life was originally in water, it would be hard to synthesize life. 2. Formation of the "self-replicating" system. Non-living organisms can't reproduce abiotically, which is obviously a large factor in the growth of life. Prokaryote 5 Correct Answer: Cells without membrane bound nucleus or organelles. Pro- = Before, - Kary = Nucleus Eukaryote Correct Answer: Cells with a true membrane bound nucleus. Eu- = true, -Kary = Nucleus Heterotroph Correct Answer: Organisms that are nourished from outside sources. Hetero- = different, -Troph = nourishment Autotroph Correct Answer: Organisms that produce their own nourishment/food. Ex: photosynthesis. Auto- self, -Troph = nourishment How old is the Earth? Correct Answer: About 4.5 billion years old How long did it take for Earth to cool? Correct Answer: 600 million years for the atmosphere to cool down. How old is the oldest fossil? Correct Answer: 3.7-3.8 billion years old. (stromatolite fossil) 6 First-living organism speculated by scientists Correct Answer: Prokayotic Heterotrophic anaerobes. Although the oldest fossils found is only 3.5 billion years old, they still believe heterotrophic organisms evolved before autotrophic. The reason being that there were plenty of macromolecules in the atmosphere present at that time Obligate Anaerobic Correct Answer: Cannot be in the presence of oxygen, it is killed by oxygen. Facultative Anaerobic Correct Answer: Can be in the presence of oxygen (not destroyed by it) but it does NOT use it Chemotrophs Correct Answer: use energy of chemical reactions (inorganic compounds) to produce food. (No sunlight). Probably arose deep in ocean vents where no sunlight was present and used H2S rather than sunlight to synthesize food Phototrophs Correct Answer: use the energy of light to build up food molecules. Photo- = light. Cynobacteria 7 Correct Answer: Prokaryotic synthesizer, earliest fossils were stromatolites, which is a type of phototrophic cynobacteria H2S vs H2O Correct Answer: H2S was originally being used to be the source of high energy electrons in photosynthesis because the first organisms were anaerobic (the byproduct then became sulfur). Eventually, H2O became the source of high energy electrons in photosynthesis (the byproduct then became oxygen). Oxygen Crisis Correct Answer: Oxygen is a corrosive element to organic molecules and therefore likely created a crisis form many of the earliest life forms. The fact that organisms were anaerobic caused a huge crisis. Endosymbiotic Hypothesis Correct Answer: Idea that a primitive anaerobic heterotrophic prokaryote (that lacked protection against effects of oxygen) formed a symbiosis with an oxygen-consuming, energy-producing bacteria (could produce ATP via oxidative phosphorylation) by consuming them. True/False: it is likely that the chloroplast evolved prior to the mitochondria Correct Answer: False. Virtually all eukaryotes have mitochondria, which offers strong evidence that the mitochondria was the first to evolve. 8 Pre-cambrian Correct Answer: Not considered a true era. Began 4.5 billion years ago, ended 600 million years ago. Earliest traces of life found (stromatolite fossil) (What year) Correct Answer: 3.8 billion years ago Oldest fossils of a complete cells (what year) Correct Answer: 3.5 billion years ago Oxygen levels rise (year) Correct Answer: 2.7 billion years ago Rise of eukaryotic cells Correct Answer: 2.2 billion years ago Paleozoic Era Correct Answer: Began 600 million years ago, ended 240 million years ago. What age did Pangaea form? Correct Answer: 245 million years ago 9 Permian extinctions Correct Answer: Extinction of many marine and terrestrial organisms (245 million years ago) Highest Point of Earth Correct Answer: Himalayan Mountains in India Lowest Point on Earth Correct Answer: Mariana Trench in the western part of the Pacific Ocean Mesozoic Era Correct Answer: Began 230 million years ago, ended 65 million years ago with the cretaceous extinctions Cretaceous Extinction Correct Answer: 65 million years ago an asteroid hit the Yucatan Peninsula in the Gulf of Mexico causing cretaceous extinction. Almost everything in North America died in seconds and this marked the end of the mesozoic era. Upper Part of Pangaea Correct Answer: Laurasia 10 Lower Part of Pangaea Correct Answer: Gondwana Cenozoic Era Correct Answer: WE ARE STILL IN THIS PERIOD. Began 65 million years ago. Life's Time Clock Correct Answer: Humans have been around in a relatively short period of time in the grand scheme of things. (1 minute on a 24 hour clock according to Brooks) Taxonomy Correct Answer: The science of identifying, classifying, and naming things. Binomial Nomenclature Correct Answer: bi- = two, nomi- = name. System of naming developed by Linnaeus that gives each organism 2 names. Genus (noun), species (adjective). Carl Linnaeus Correct Answer: Goal was to name every species on the planet. He came up with Binomial Nomenclature Classification System 11 Correct Answer: Domain (Domains) = Divine Kingdom (Kingdoms) = King Phylum (Phyla) = Phillip Class (Classes) = Came Order (Orders) = Over Family (Families) = From Genus (Genera) = Greece Species = Singing Binary Fission Correct Answer: Asexual reproduction. Used in bacteria Mutualism Correct Answer: Benefit both organisms Commensalism Correct Answer: One benefits, no effect on the other Parasitism Correct Answer: One benefits, the other is harmed coccus Correct Answer: circle shaped bacteria 12 bacillus Correct Answer: rod shaped bacteria spirillus Correct Answer: spiral shaped bacteria Domain Eukarya Correct Answer: Kingdom Archezoa Kingdom Protista Contain a true nucleus Serial Endosymbiotic Hypothesis Correct Answer: Hypothesis that mitochondria came first then chloroplast. Mitochondria and chloroplast were thought to have come from Eukaryotes Kingdom Archezoa Correct Answer: Create ATP anaerobically (without oxygen) Have a true nucleus, but lack mitochondria Giardia Correct Answer: Kingdom Archezoa Intestinal parasite of vertebrates 13 Caused intestinal issues which you can get from drinking tainted water Kingdom Protista Correct Answer: Typically they are eukaryotes which means that they have a defined nucleus Typically unicellular though some are multicellular unicellular: ciliates multicellular: ulva Very Diverse Group Classification based on ecological role: Consumer - Heterotrophic Producer - Autotrophic Both - Mixotrophic Polyphyletic Correct Answer: Protists are polyphyletic, meaning that they evolved similar characteristics, but not one RECENT common ancestor. Monophyletic Correct Answer: One recent common ancestor Heterotrophic protists Correct Answer: All end with -mycota which means fungus!! 14 Fungus-like "water molds", slime molds, and plasmodial slime molds Phylum Chytidiomycota, Phylum Oomycota, Phylum Acrasiomycota, and Phylum Myxomycota Phylum Chytridiomycota Correct Answer: Heterotrophic Protists Spores responsible for amphibian disease Chytridiomycosis (important) which is rapidly killing many amphibians globally Phylum Oomycota Correct Answer: Require water to survive Can reproduce sexually via the Oogonium Can reproduce asexually via Zoospores Phylum Acrasiomycota Correct Answer: Cellular slime mold Unicellular protist, however can be colonial (aggregate of cells) It is not a TRUE plasmodium because it aggregates Cells used cAMP (acrosin) as a pheromone which cause the organisms to gather together and create a pseudoplasmodium (colony) when food is found Reproduce via sporangium (structures that produce spores) Fully undergoes mitosis UNLIKE plasmodial slime mold 15 Phylum Myxomycota Correct Answer: Plasmodial Slime Mold Forms a multinucleated cell mass known as plasmodium. This is because it does not undergo cytokinesis (cell division) Multinucleate organisms with one big cell, which is why they are called plasmodium in contrast with pseudoplasmodium which is many cells that look like one due to aggregation When food/water runs out, plasmodium then grow sporangium (structures that release spores for sexual reproduction) Phylum Sarcodina Correct Answer: sarco- = flesh/muscle, -dina = to spin/whirl All have pseudopodia (cellular extensions used to move and feed) Types: Amoebae Foraminiferians Radiolarians Amoebae Correct Answer: Moves around in an amorophus way uses lobed pseudopodia for locomotion and feeding (endocytosis) This is why they are classified as pseudopods Phylum Sarcodina 16 Foraminiferians Correct Answer: Pseudopods that have Calcium Carbonate shells (ex: snails) use thin pseudopodia (axopodia) for feeding Phylum Sarcodina Radiolarians Correct Answer: Pseudopods that have silica shells, giving them a glass-like appearance (more transparent) Use thin ray-like pseudopodia (axopodia/acitinopodia) for feeding and movement Phylum Sarcodina Phylum Ciliophora Correct Answer: Ciliated, meaning that they use cilia for feeding and locomotion most are freshwater They have specialized organelles: 1. Contractile Vacuole 2. Extensive Cytoskeletal network 3. macronuclei 4. micronuclei examples: Paramecium (most complex cell), Trichocysts (know both*) Contractile Vacuole 17 Correct Answer: Organelle in Phylum Ciliophora Central vacuole used for pumping out excess water ("water bailer") Needed because the organism lives in freshwater and so that it doesn't lyse (explode) Macronuclei Correct Answer: Synthesized DNA and RNA, assist reproduction and food production Organelle in Phylum Ciliophora Micronuclei Correct Answer: synthesizes DNA only and differentiation Paramecium Correct Answer: Phylum Ciliophora Most famous ciliate and most complex cell Trichocysts Correct Answer: type of ciliate that can sting and captures its food by stinging it Phylum Mastigophora Correct Answer: "Zooflagellates" Unicellular flagellates characterized by having flagella Mostly parasited and commensals, meaning that they are SYMBIOTIC Ex: Trypanosoma, Trichomonad, and Choanoflagellate 18 Trypanosoma Correct Answer: Phylum Mastigophora African Sleeping Sickness Transmitted from the Tse Tse fly Humans can get the African Sleeping sickness as well as domesticated animals. Wild animals generally cant get this disease due to an immunity Look like little eels and can also cause Chagas disease Trichomonad Correct Answer: Phylum Mastigophora Can cause Trichomonaisis which cause tissue inflammation and can actually be classified as an STD. Mostly affects females Choanoflagellates Correct Answer: Has a cell structure very similar to animal called a sponge Phylum Apicomplexa Correct Answer: Parasites They have different life stages They are non-motile as adults (they don't move) Attach to tissues of a vector (host) 19 Ex: Malaria Malaria Correct Answer: Phylum Apicomplexa Plasmodium (italics) not to be confused with slime mold's multinucleated plasmodium (no italics) Four Life Stages: (Smart Children Make Games) 1. Sprozoite - carried in the glands of a mosquit0, then once infected hide in the liver of the host 2. Cryptozoite - carried in the liver of the host 3. Merozoite - enter red blood cells in the liver and attack 4. Gametocyte - when ruptured from red blood cells, spread throughout Phylum Euglenophyta Correct Answer: Mixotrophic Chlorophyll A & B (KNOW!) Uses flagellum for locomotion No cell wall Stigma (eyespot) (know!) Ex: Euglena Stigma Correct Answer: Phylum Euglenophyta 20 Eye Spot Can detect light which allows them to move towards light for photosynthesis Phylum Pyrrophyta Correct Answer: "Dinoflagellates" Chlorophyll A & C, plus other pigments(KNOW!) Have 2 flagella that spin perpendicular to each other that cause them to move through the water Cellulose cell wall (Similar to plants) Ex: Pfiesteria, Zooxanthellae, and Bioluminescence (KNOW ALL!) Pfiesteria Correct Answer: Phylum Pyrrophyta "The Cell From Hell" Can eat flesh and are actually carnivores Responsible for Red Tides Red Tides Correct Answer: Phylum Pyrrophyta Responsible for massive fish kills and Paralytic Shellfish Poisoning Caused from Pfiesteria Zooxanthellae 21 Correct Answer: Phylum Pyrrophyta Symbiotic relationship with coral Live in shallow water They live in coral and actually help corals live since coral can eat it. Help coral produce calcium carbonate (Which is white) When H2O rises, dinoflagellates leave the coral and coral turns white losing its color which is called bleaching Bioluminescence Correct Answer: Some dinoflagellates can give off light causing a phenomenon called bioluminescence Caused from dinoflagellates being agitated Phylum Pyrrophyta Phylum Chrysophyta Correct Answer: "Gold-Brown Algae" Chlorophyll A & C (KNOW!) Cell wall (if present) is made of cellulose or pectin Ex: Diatoms Diatoms Correct Answer: Phylum Chrysophyta Significant O2 Source, they produce more O2 than any other autotroph 22 Used in some toothpaste Cell walls are not always present, but if so they are made of cellulose or pectin Phylum Rhodophyta Correct Answer: "Red Algae" Chlorophyll A & D (know!) and deepwater pigments Cellulose cell walls Coraline Algae/Calcareous meaning that they produce calcium carbonate and when they die they break down into sand which causes pink beaches Produce Carageenan and Agar Carageenan is used in ice cream, and makeup Phylum Phaeophyta Correct Answer: "Brown Algae" Typically multicellular, can get large & plant like Chlorophyll A & C plus other pigments (KNOW!) Specialized plant-like structures: 1. Holdfast (root-like) 2. Stipe (stem-like) 3. Frond (leaf-like) 4. Vessel Cells Prefer cold water Ex: Kelps and Sargassum (floating ecosystem and found on our beaches) 23 Alginic acid extract is an emulsifier Has commercial uses: Makeup, food thickeners, etc... Phylum Chlorophyta Correct Answer: "Green Algae" Chlorophyll A & B (just like land plants) Diverse assemblage, marine and freshwater Multicellular Example: Codium - abundant due to waste water run off (video) Colonial Example : Volvox Cellulose wall just like land plants Likely link to higher plants (most recent ancestor to higher plants)