Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
BioExam2
Ch.25
| Vocabulary | Definition |
|---|---|
| abiogenesis | Is the scientific study of how life on earth could have arisen from inanimate matter (it is distinct from evolution) |
| life | Has requirements such as homeostasis, growth, reproduction, metabolism, and response to stimuli |
| monomers | (amino acids, nucleotides) |
| polymers | (proteins, nucleic acids) |
| Oparin-Haldane hypothesis | Organic compounds can (meaning it is possible) form in a reducing atmosphere with UV radiation, resulting in a "primitive soup" this was developed in the 1920's |
| protobionts | Abiotically produced molecules surrounded by a simple membrane layer like structure- "Earliest life form" |
| ribozymes | RNA that act as catalysts and replicators (Cech and Altman won Nobel prize for discovering them in 1989) |
| stromatolites | Layered rock formed from prokaryotes binding films of sediment together- first evidence of life (3.5 bya) |
| isotopes | Different forms of the same element with different numbers of neutrons (same number of protons and electrons) |
| carbon dating | Carbon dating is a technique used to determine the approximate age of once-living materials. It is based on the decay rate of the radioactive carbon isotope 14C, a form of carbon taken in by all living organisms while they are alive |
| half-life | The time required for 50% of isotope to decay. C-14=5730 yrs |
| six major events in life's history | 1) 3.5 bya Prokaryotes (first life) 2) 2.2 bya Cyanobacteria and atmospheric O2 3) 2.1 bya First eukaryotes (single celled) 4) 1.9 bya Multicellular eukaryotes 5) 535 mya Cambrian explosion 6) Terrestrial organisms-colonization of land |
| banded iron formations | Evidence that atmospheric oxygen was produced 2.7 bya; by photosynthesis reacted with dissolved iron and precipitated out |
| cyanobacteria | Photosynthetic organisms, lead to atmospheric oxygen by 2.7 bya |
| endosymbiosis | Explains that mitochondria and plastids (chloroplasts and related organelles) were formerly small prokaryotes living within larger host cells. |
| key evolutionary innovations | Some examples are eukaryotic cell, multicellularity, and colonization of land. |
| adaptive radiation | Many new species from one ancestor whose adaptations allow them to fill different ecological roles. Can result from colonization of new habitat, massive extinctions, and key evolutionary innovations. |
| continental drift | Part of the rise and fall of dominant groups, it plays a big role. Continents are always in constant motion. |
| pangaea | A supercontinent that existed during the Paleozoic and Mesozoic era. |
| mass extinction | Where a major event causes more than 50% of Earth's species to become extinct. |
| Ediacaran | Ear where there was large diverse eukaryotes, all soft bodied occurred 565 mya |
| Cambrian | Era where there mostly soft bodied herbivores, filter feeders and scavengers between 525 to 535 may echinoderms, chordates, brachiopods, annelids, and arthropods lived |
| evo-devo | Interface of evolution & development. A field of biology that compares developmental processes of different multicellular organisms to understand how these processes have evolved and how changes can modify existing organismal features or lead to new ones. |
| heterochromy | Evolutionary change in the rate or timing of developmental events. |
| paedomorphosis | An extreme form of heterochrony where juvenile structures of ancestral species maintained in adults. |
| homeotic genes | Master regulatory genes that control placement and spatial organization of body parts. Ex: Hox Genes |
| gene expression | Where and when genes are expressed. The process by which DNA directs the synthesis of proteins or, in some cases, just RNAs |
| transitional fossils=intermediate forms | The fossil record seems to reveal trends in the evolution of many species and lineages an example would be horses |
| irreducible complexity argument | The argument that certain biological systems are too complex to have evolved from simpler predecessors, it has two key points: Things can be lost during evolution not just gained and Dependence can evolve after independent parts. |
| exaptation | Some structures are co-opted (appointed) for a different function. |
| cladistics | Is how we build phylogenies, its an approach to systematics in which organisms are placed into groups called clades based primarily on common descent. |
| parsimony | States that the cladogram implying the least number of changes in character states is the best. It's based on occam.'s razor (use the simplest explanation. |
| phenetics | Bases classification strictly on similarities among organisms. |
| shared derived character | Is only homologous for a clade (it is not in the previous ancestor). A unique character to a particular organism or clade |
| shared ancestral character | Is homologous (inherited, common) for a clade and a previous ancestor. A character shared by ancestor and all descendants; also known as a shared primitive trait |
| analogy | Similarity between two species that is due to convergent evolution rather than to descent from a common ancestor with the same trait. This is useless for determining evolutionary relationships. |
| homoplasy | Similar to analogy where similarity in organisms evolve independently and not inherited from a common ancestor. |
| homology | Similar structures due to common ancestry; inherited. |
| clade | A monophyletic group, a group of organisms (taxa) and their most recent common ancestor, an ancestral species and all of its descendants. |
| monophyletic group | Is a whole clade including includes an ancestral species and all its descendants. |
| paraphyletic group | Includes an ancestral species but is missing one or more descendants. |
| polyphyletic group | Includes taxa with different ancestors (no common ancestor) or missing an ancestor. |
| outgroup | A taxon that diverge before the taxa of interest or in-group. Meaning a species or group of species from an evolutionary lineage that is known to have diverged before the lineage that contains the groups of species being studied |
| ingroup | Diverged from the outgroup, its the species studied that branch off. These are the species or group o species whose evolutionary relationships we seek to determine. |
| occam's razor | The simplest explanation that is consistent without the facts, tends to be the best one (because it most probable). |
| phylogenetic tree | A branching diagram that represents a hypothesis about the evolutionary history of a group of organisms. |
| molecular homoplasy | Strands of DNA froth same area of the same gene from two organisms being compared |
| maximum likelihood | A principle that sates that when considering multiple phylogenetic hypothesis, one should take into account the hypothesis that reflects the simplest explanation that is consistent with the facts |
| molecular clock | A method for estimating the time required for a given amount of evolutionary change, based on the observation tat some regions of gnomes appear to evolve at constant rates |
| neutral theory | The hypothesis that much evolutionary change in genes and proteins has no effect on fitness and therefore is not influenced by Darwinian natural selection, developed in the 1960s. |
| orthologous genes | Homologous genes that are found in different species because of speciation, they are widespread and can be ancient. |
| paralogous genes | Homologous genes that are found in the same genome as a result from gene duplication in same species. |
| systematics | The study of biological diversity in an evolutionary context. Its a scientific discipline focused on classifying organisms and determining their evolutionary relationships |
| phylogeny | The evolutionary history (relationship) of a species or group of related species |
| domain | A taxonomic category above the kingdom level. It contains three Archaea, Bacteria, and Eukarya |
| kingdom | A taxonomic category, the second broadest domain. |
| phylum | In classification, the taxonomic category above class |
| class | in classification, the taxonomic category above the level of order |
| order | In classification, the taxonomic category above the level of family |
| family | In classification, the taxonomic category above genus |
| genus | A taxonomic category above the species level, designated by the first word of a species' two-part scientific name |
| species | A taxonomic category below the genus level |
| taxa/taxon | A named taxonomic unit at any given level of classification |
| node/branch point | Resembles an ancestor on a phylogenetic tree/Represents the divergence of two or more taxa from a common ancestor |
| sister taxa | Two taxa next to each other. Groups of organisms that share an immediate common ancestor and hence are each other's closest relatives |
| polytomy | In a phylogenetic tree, a branch point from which more than two descendant taxa emerge. It indicates that the evolutionary relationships among the descendant taxa are not yet clear(an unresolved pattern of divergence) |
| rooted | Describing a phylogenetic tree that contains a branch point (typically, the one farthest to the left) representing the last common ancestor of all taxa in the tree |
| bacteria | One of two prokaryotic domains, has a cell wall that contains peptidoglycan |
| eukarya | The domain that contains all eukaryotic groups, they have a nucleus, no circular DNA, no plasmids, have ribosomes (they work different than the ribosomes in prokaryotes) |
| archaea | One of two prokaryotic domains, the other being bacteria. |
| monera | One of the taxonomic kingdoms in the old biological classification system that consisted of prokaryotes, particularly bacteria, archebacteria, and blue-green algae |
| prokaryote | Unicellular ( a few exceptions) organisms whose cells lack a cell nucleus or any membrane-encased organelles |
| cell wall | Helps maintain cell shape, protects cell and prevents the cell from bursting in a hypotonic environment |
| gram staining | A simple way to separate bacteria into two large groups, based upon how their cell walls respond to staining, this is done on bacteria |
| peptidoglycan | A type of polymer in bacterial cell walls consisting of modified sugars cross-linked by short polypeptides |
| pili/fimbriae | A hairlike structure that is used to move around and stick to things as well as to have sex |
| flagellum | A long cellular appendage specialized for locomotion |
| plasma membrane | The membrane at the boundary of every cell that acts as a selective barrier, regulating the cell's chemical composition |
| nucleoid | A dense region of DNA in a prokaryotic cell |
| ribosomes | The closes organelle you will find in prokaryotes, they function as a site of protein synthesis in the cytoplasm |
| plasmid | Small rings of double stranded DNA, these are accessory genes |
| binary fission | A method of asexual reproduction by "division in half". In prokaryotes it does not involve mitosis but in single-celled eukaryotes it goes thru mitosis |
| endospore | A thick coated, resistant cell produced by a bacterial cell exposed to harsh conditions |
| horizontal gene transfer | Any process in which an organism incorporates genetic material from another organism without being the offspring of that organism |
| vertical gene transfer | A process in which an organism receives genetic material from its ancestor |
| transformation | Absorption and integration of fragments of DNA from the environment |
| transduction | Bacteriophages (viruses) transfer genes between prokaryotes |
| conjugation | One cell directly transfers genes to another cell (bacteria "sex") |
| bacteriophage | A virus that infects bacteria; also called a phage |
| F+/F- plasmid/cell | The ability to form sex pill encoded in a piece of DNA, the positive contains the information and the negative does not contain any information |
| R plasmid | A bacterial plasmid carrying genes that confer resistance to certain antibiotics |
| metabolism | The basic way an organism functions, its the set of chemical reactions that occur in living organisms to maintain life, grow and reproduce |
| catabolism | Breaks down organic matter and harvest energy |
| anabolism | Uses energy to construct organic molecules |
| photoautotroph | Are photosynthetic organisms that harness light energy to drive the synthesis of organic compounds from CO2 (basically plants) |
| chemoautotroph | Need only CO2 as a carbon source, but they brain energy by oxidizing inorganic substances, rather than light |
| photoheterotroph | Use light to generate ATP but obtain their carbon in organic form. This isn't very common |
| chemoheterotroph | Must consume organic molecules for both energy and crab. Seen not only in prokaryotes but also in herbivores, carnivores, parasites, etc. |
| taxis | Movement towards or away from a stimulus |
| cooperation | Behaviors that benefit other individuals |
| chemotaxis | Movement towards or away from chemicals (O2, nutrients, other individuals) |
| quorum sensing | A method of communication between bacteria that enables the coordination of groups behavior based on population density |
| biofilm | A bunch of microorganisms that are stuck together (and often to a surface) |
| symbiosis | An intimate and often obligatory association between individuals of tow species |
| mutualism | An association between two organisms that benefits both |
| commensalism | An association between two organisms where one benefits while neither harming nor helping the other |
| parasitism | An association between two organisms where one organism benefits while the other is harmed |
| endotoxin | Are toxic components of outer membranes of some gram-negative bacteria. Ex: salmonella typhi |
| exotoxin | Are proteins secreted by prokaryotes. Ex:botulinum toxin |
| nitrogen cycle | The natural process by which nitrogen, either from the atmosphere or from decomposed organic material, is converted by soil bacteria to compounds that can be assimilated by plants. |
| nitrification | The oxidation of ammonium compounds in dead organic material into nitrates and nitrites by soil bacteria (making nitrogen available to plants). |
| nitrogen fixing | The conversion of atmospheric nitrogen to ammonia. |
| Protist | Any eukaryote that is not a plant, animal or fungus; it is paraphyletic |
| fermentation | Does not use O2, in cytoplasm, prokaryotes and eukaryotes |
| glycolysis | The splitting of glucose into pyruvate. Serves as the starting point for fermentation or cellular respiration |
| aerobic respiration | Uses O2, in protobacteria and mitochondria of eukaryotes |
| photosynthesis | The conversion of light energy to chemical energy that is stored in sugars or other organic compounds |
| plastid | Family of specialized plant organelles (chloroplasts, amyloplasts etc) |
| mixotroph | An organism that is capable of both photosynthesis and heterotrophy |
| gamete | A haploid reproductive cell, such as an egg or sperm. They unite during sexual reproduction to produce a diploid zygote |
| zygote | The diploid product of the union of haploid gametes during fertilization; a fertilized egg |
| gametophyte | In organisms that have alternation of generations, the multicellular haploid form that produces haploid gametes by mitosis. The haploid gametes unite and develop into sporophytes |
| sporophyte | In organisms that have alternation of generations, the multicellular diploid form that results from the union of gametes. They produce haploid spores by meiosis that develop into gametophytes |
| alternation of generations | A life cycle in which there is both a multicellular diploid form (sporophyte) and a multicellular haploid form (gametophyte) |
| mitosome/hydrogenosome | An organelle found in some unicellular eukaryotic organisms as well as a membrane-bound organelle found in some anaerobic fungi and protozoa that is involved in the production of hydrogen and carbon dioxide. |
| vector | An organism that transmits pathogens from one host to another |
| intermediate host | An organism in or on which a parasite develops to an adult but not sexually mature stage. |
| cilia | Used to help move and feed |
| pseudopodia | Are extensions of the cytoplasm with anchors |
Created by:
ansecaballero
Popular Biology sets