Marb 435 1st Edition Exam 1 Study Guide Lectures 1 7 Introduction Question 1 Approximately what percentage of all animal species are invertebrates 98 of all animal species are invertebrates Question 2 Which invertebrate taxa have the most number of species in the ocean Mollusca with about 52 525 species Question 3 Give examples of the economic significance of invertebrates Critical role in most food webs Sources for pharmaceuticals Directly or indirectly cause many diseases in humans animals and plants Can become invasive and cause local extinctions and other problems Model systems for many fields of study Question 4 What is a binomial species name and what parts does it consist of A binomial name was the way to classify organisms using Latin binomials Carolus Linnaeus was the first to use this system It consists of the genus and species of the animal written in italics with the genus name capitalized but the species name lower case Example Rosa sylvestris Question 5 What can you infer about the species description and its author when you see this species name Littorina irrorata Say 1822 If a later author placed the species in a different genus the name of the original author and year of original publication are listed in parenthesis so this would mean that the species was renamed and they are giving credit to the original person who named it first Question 6 Name all taxonomic categories from the most inclusive to the least inclusive one Kingdom Phylum Class Order Family Genus Species Phylogenetics Question 1 Which 20th century German entomologist is considered the founder of Phylogenetic Systematics Willi Hennig Question 2 Study the phylogenetic tree of Drosophila speices Based only on the tree decide whether the following statements are true T false F or impossible to infer N A The melanogaster group is monophyletic TRUE D virilis and D mojavensis are sister taxa TRUE The tree is ultrametric TRUE D erecta and D yakuba are sister taxa FALSE Wings are a synapomorphy for Drosophila N A because we don t know its ancestors The obcura group and the melanogaster group diverged almost 30 million years ago TRUE The tree is only partially resolved FALSE The obscura group is polyphyletic TRUE Drosophila belongs in the subphylum Insecta and in the phylum Arthropoda TRUE Question 3 Give brief definitions of the terms autapomorphy synapomorphy monophyletic group paraphyletic group polyphyletic group Autopamorphy Character state unique to a taxon however it is phylogenetically uninformative Synapomorphy Derived character state that is shared by all members of a group Paraphyletic Group a group of species that does not include all descendants of an ancestral species Monophyletic group a group of species that includes all descendants of a common ancestor Polyphyletic group a group of species that has no direct common ancestor Question 4 How many character states do you usually have for each nucleotide position in a DNA sequence What are they Molecular Data DNA or protein sequence data Each nucleotide position is a character DNA has four character states ACGT Question 5 Invertebrates are Monophyletic Paraphyletic Polyphyletic All of the above Question 6 Which of the following is correct Check all that apply The eyes of vertebrates and octopuses are homologous The eyes of vertebrates and octopuses are analogous The eyes of vertebrates and octopuses are paraphyletic The eyes of vertebrates and octopuses are results of convergent evolution The eyes of vertebrates and octopuses are a synapomorphy Zooplankton Question 1 Define plankton neuston and nekton 1 Plankton Drifting organism that inhabit the water column of seas oceans or lakes Passive transport with currents Often capable of vertical migration in the oceans water columns 2 Neuston Type of plankton that is specifically associated with the uppermost layer of the water column at the surface or just below 3 Nekton Organisms that live in the water column of seas oceans and lakes and can propel themselves independently of the water currents Question 2 Which size of zooplankton are you mostly going to capture with a plankton net of 200 m mesh size Which organisms will probably dominate the sample Mesozooplankton 0 2 20 mm Copepods often represent 50 90 of the catch Question 3 Explain the difference between direct and indirect development Direct development 1 It is a type of development in which an embryo develops into a mature individual without involving a larval stage 2 Metamorphosis is absent 3 It occurs in fishes reptiles birds and mammals Indirect development 1 It is a type of development that involves a sexually immature larval stage having different food requirements than adults 2 Metamorphosis involving development of larva to a sexuallymature adult is present 3 It occurs in most of the invertebrates and amphibians Question 4 Give examples of metazoans that are holoplanktonic and meroplanktonic respectively Holoplankton spend their entire lives in planktonic form Examples of holoplankton include some diatoms radiolarians some dinoflagellates foraminifera amphipods krill copepods and salps Meroplankton are planktonic for only part of their life cycles often are the larvae of many marine invertebrates Examples of meroplankton include the larvae of sea urchins sea stars crustaceans marine worms some marine gastropods and most fish Question 5 Give a few examples of how planktonic invertebrates can avoid or defend themselves against predation Transparence Protective Spines Chemical Defenses distasteful or toxic o EXAMPLE Small amounts of didemnins from larvae or adults of the Caribbean tunicate Trididemnum solium cause vomiting in fish Diel swimming rhythms Synchronized mass spawning Abbreviated larval phases Question 6 Explain ocean acidification and what effect it may have on plankton CO2 forms bicarbonate HCO3 and carbonate CO32 in seawater lowering the pH Increase in net phytoplankton productivity might sustain more zooplankton BUT reduced calcification Ca2 2 HCO3 CaCO3 CO2 H2O With increased CO2 equilibrium shifts to the left Affects some phytoplankton and zooplankton Metazoa Question 1 What are the two main components of the cytoskeleton in eukaryotic cells 1 Microfilaments molecules arranged in a helix and are made of actin 2 Microtubules hollow cylindrical structures with subunits that are heterodimers of atubulin and B tubulin Question 2 Which materials do the tests of radiolarians and foraminiferans consist of respectively