the branch of biology that studies the diversity of life and its evolutionary relationships
the science that identifies, names and classifies new species
Swedish Naturalist; was the first practitioner of Taxonomy
a group of species with similar characteristics located within the binomial system of nomenclature
Species Name, utilized with the binomial nomenclature
The organisims included within any category of the taxonomic categories
formal hypotheses that identify likely relationships among species and higher taxonomic groups.
a Branch on a phylogenetic tree
comprises one clade - an ancestral species and all of its descendants but no other species
A taxon that includes an ancestor and some but not all of its descendants.
similarities that result from shared ancestry
Organisms that are not closely related but bear a striking resemblance to one another, especially when exposed to similar patterns of natural selection.
Determined by DNA or RNA to determine Systematics
The totality of fossilized artifacts and their placement within the earth's rock strata. It provides information about the history of life on earth, for instance what the organisms look like, where and when they live, how they evolved, etc.
The action of classifying genus and species utilitizing latin as the language in which to do so
Classification of Species
Domain, Kingdom, phylum, class, order, family, genus, species
the classificaltion of organisms based on their actural genetic similarity
Shared Primitive Character
A characteristic that when it appears it is shared with all its descendants for example the spine
Group of species that share the same characteristics
Species closely related to the study group but not entirely similar
Common ancestry over a particular timeframe and divergence within.
Branching pattern that can be traced from ancestor to the present are the same
the homologous genes pass in a straight line from one generation to next but end up in separate gene pools
show up from duplication of the gene it is not linear it branches.
the average rate at which a species' genome accumulates mutations, used to measure their evolutionary divergence
Developed by Matoo Kimura.
The hypothesis that much evolutionary change in genes and proteins has no effect on fitness and therefore is not influenced by Darwinian natural selection
One of the 2 domains of prokaryotes; collectively, bacteria are the most metabollically diverse organisms
one of 2 domains of prokaryotes; these have some unique molecular and biochemical traits, but they also share some traits with bacteria and other traits with eukarya
the domain that includes all eukaryotes, organisms that contain a membrane-bound nucleus within each of their cells; all protists, plants, fungi, and animals
an organism consisting of a cell or cells in which the genetic material is DNA in the form of chromosomes contained within a distinct nucleus. Eukaryotes include all living organisms
A. L. Oparin
developed primordial soup theory, which said that something triggered certain elements into a living cell
a solution rich in organic compounds in the primitive oceans of the earth, from which life is hypothesized to have originated.
Miller Urey Experiment
an experiment that simulated the conditions thought at the time to be present on the early Earth, and tested for the occurrence of chemical origins of life. Specifically, the experiment tested Alexander Oparin's and J. B. S. Haldane's hypothesis that conditions on the primitive Earth favored chemical reactions that synthesized more complex organic compounds from simpler organic precursors. Considered to be the classic experiment concerning the experimental abiogenesis, it was conducted in 1953 by Stanley Miller and Harold Urey at the University of Chicago and later the University of California, San Diego and published the following year
without life, chemical and mineral elements combine to create a living cell
amino acids- protein producing part of organisms, very important to membrane
multiple subjects that receive either the same experimental treatment or the same control treatment
the chemical processes that occur within a living organism in order to maintain life.
an RNA-based catalyst that is part of the biochemical machinery of all cells.
predicting the age of fossils based on decay of radioactive isotopes
the time it takes for half of a given amount of radioisotope to decay
refers to the entirety of the layers of rock strata — deposits laid down in volcanism or by sediment deposition of weathering detritus (clays, sands etc.) including all its fossil content and the information it yields about the history of the Earth: its past climate, geography, geology and the evolution of life on its surface
the eon that constitutes the later part of the Precambrian, between the Archean eon and the Cambrian period, in which the earliest forms of life evolved
characterized by the appearance of bacteria and marine algae
the era between the Precambrian eon and the Mesozoic era. characterized by the advent of fish, insects, and reptiles.
an era occurring between 230 and 65 million years ago, characterized by the appearance of flowering plants and by the appearance and extinction of dinosaurs.
the present era, beginning 65 million years ago and characterized by the ascendancy of mammals
a period of the Paleozoic Era occurring from about 280 to 230 million years ago and characterized by a profusion of amphibian species.
a period of the Mesozoic Era, from 140 million to 65 million years ago, characterized by the greatest development and subsequent extinction of dinosaurs and the advent of flowering plants and modern insects
a calcareous mound built up of layers of lime-secreting cyanobacteria and trapped sediment, found in Precambrian rocks as the earliest known fossils
a microscopic network of protein filaments and tubules in the cytoplasm of many living cells, giving them shape and coherence.
symbiosis in which one of the symbiotic organisms lives inside the other.
a four-footed animal, esp. a member of a group that includes all vertebrates higher than fishes.
the gradual movement of the continents across the earth's surface through geological time.
a supercontinent that existed during the late Paleozoic and early Mesozoic eras, forming approximately 300 million years ago. It began to break apart around 200 million years ago.
Protists are a large and diverse group of eukaryotic microorganisms
are represented by mainly unicellular algae. These organisms are mostly planktonic and represent the phytoplanktons which account for nearly 80% of the total photosynthetic activity in the biosphere.
Primary endosymbiosis involves the engulfment of a bacterium by another free living organism. Secondary endosymbiosis occurs when the product of primary endosymbiosis is itself engulfed and retained by another free living eukaryote.
involving, or requiring an absence of free oxygen.
2 equally sized nuclei and multiple flagella
abnormal mitochodria, flagellated protists, form symbiotic relationships with animals
a group of single-cell flagellate protozoa, including a number of parasites responsible for serious diseases in humans and other animals,
Protist autotroph, photosynthetic photo taxic
marine and freshwater green or colorless flagellate organism
the fusion of two cells, or of their nuclei, in reproduction.
protist, membrane bound sac under the plasma membrane
population explosion of organisms because of the appearance of Carotenoids
allow plants to carry out photosynthesis; some are bioluminous, created by ATP chemical reaction
A symbiotic relationship between individuals of different species in which both individuals benefit from the association.
A large group of protozoans that are characterized by having a special organelle called an apical complex. Most of them are single-celled, parasitic, and spore-forming.
One of the minute elongated bodies resulting from the repeated division of the oocyst. In the case of the malarial parasite, it is the form that is concentrated in the salivary glands and introduced into the blood by the bite of a mosquito; it enters the liver cells and infects the red blood cells to initiate clinical malaria.
An apicoplast is a derived non-photosynthetic plastid found in most Apicomplexa, including malaria parasites such as Plasmodium
a mosquito of a genus that is particularly common in warmer countries and includes the mosquitoes that transmit the malarial parasite to humans.
a single-celled animal of a phylum distinguished by the possession of cilia or ciliary structures. The ciliates are a large and diverse group of advanced protozoans.
the larger type of nucleus in ciliates. Macronuclei are polyploid and undergo direct division without mitosis. It controls the non-reproductive cell functions, the everyday tasks, such as metabolism
is the smaller nucleus in ciliate protozoans, such as the Paramecium. In fission it divides by mitosis, and in conjugation it furnishes the pairing of gamete nuclei, by whose reciprocal fusion a zygote nucleus is formed
the subdivision of a cell into two or more parts and the regeneration of those parts into separate cells
the fusion of two gametes, esp. when they are of a similar size
Most are algae, ranging from the giant multicellular kelp to the unicellular diatoms, which are a primary component of plankton. have smooth and hairy flagella
nonphotosynthetic fungi that resemble algae and that reproduce by forming oospores;
uses an enzyme to decompose matter
a single-celled alga that has a cell wall of silica. reproduce asexually, and stores food in laminarins
a storage glucan found in brown algae. It is used as a carbohydrate food reserve
Named for color, bi flagellinated, photosynthetic, many are clonal
largest complex algae; mostly marine, photosynthetic, commonly called sea weed
latin for golden
anchors algae to the sea bed
the stem of a seaweed
provide the surface for photosynthesis
a large brown seaweed that typically has a long, tough stalk with a broad frond divided into strips. Some kinds grow to a very large size and form underwater “forests” that support a large population of animals
thickens food, made from polymer from algae and is used to grow bacteria
alternation of Generation
applies only to life cycles in which haploid and diploid cells are multicellular
action in which sporophytes and homdiophytes do not resemble one another
a group of protists. They are sometimes described as a kingdom.
a single-celled aquatic animal that has a spherical, amebalike body with a spiny skeleton of silica. Their skeletons can accumulate as a slimy deposit on the seabed.
a single-celled animal that catches food and moves about by extending fingerlike projections of protoplasm
a temporary protrusion of the surface of an ameboid cell for movement and feeding.
a single-celled planktonic animal with a perforated chalky shell through which slender protrusions of protoplasm extend. Most kinds are marine, and when they die, their shells form thick ocean-floor sediments.
class of amoeboid protists. They are characterized both by their thin pseudopodia that form an external net for catching food, and they usually have an external shell, or test, made of various materials and constructed in diverse forms.
major group of amoeboid protozoa, including the majority that move by means of internal cytoplasmic flow. Their pseudopodia are characteristically blunt and finger-like, called lobopodia
Free-living amoebas that keep growing until they can fully wrap themselves around food
an ameba that typically lives harmlessly in the gut, though one kind can cause amebic dysentery
simple organism that consists of an acellular mass of creeping jellylike protoplasm containing nuclei,
cellular slime molds
differing from true slime molds in being cellular and nucleate throughout the life cycle
is a grouping of slime molds.
photosynthetic algae that contain chlorophyll and store starch in discrete chloroplasts. They are eukaryotic and most live in fresh water,ranging from unicellular flagellates to more complex multicellular forms.
green algae. over 7000 species
a plastid that contains chlorophyll and in which photosynthesis takes place.
any of a group of red photosynthetic pigments present in red algae and some cyanobacteria.
a green pigment, present in all green plants and in cyanobacteria,responsible for the absorption of light to provide energy for photosynthesis
green shoot or twig
a specialized connection of two adjacent animal cell membranes such that the space usually lying between them is absent.
a structure by which two adjacent cells are attached, formed from protein plaques in the cell membranes linked by filaments
a specialized intercellular connection between a multitude of animal cell-types. It directly connects the cytoplasm of two cells, which allows various molecules and ions to pass freely between cells
a diploid cell resulting from the fusion of two haploid gametes; a fertilized ovum
cell division, esp. of a fertilized egg cell.
an animal embryo at the early stage of development when it is a hollow ball of cells.
an embryo at the stage following the blastula, when it is a hollow cup-shaped structure having three layers of cells.
the process in which a gastrula develops from a blastula by the inward migration of cells
the active immature form of an insect, esp. one that differs greatly from the adult and forms the stage between egg and pupa, e.g., a caterpillar or grub
the process of transformation from an immature form to an adult form in two or more distinct stages
the relatively rapid appearance, around 542 million years ago, of most major animal phyla, as demonstrated in the fossil record. This was accompanied by major diversification of other organisms
a group of animals at a similar evolutionary level.
the quality of being made up of exactly similar parts facing each other or around an axis.
symmetry around a central axis, as in a starfish or a tulip flower.
the property of being divisible into symmetrical halves on either side of a unique plane.
relating to the underside of an animal or plant; abdominal
nearer the front, esp. situated in the front of the body or nearer to the head.
further back in position; of or nearer the rear or hind end, esp. of the body or a part of it.
any of the distinct types of material of which animals or plants are made, consisting of specialized cells and their products.
each of the three layers of cells (ectoderm, mesoderm, and endoderm) that are formed in the early embryo.
the outermost layer of cells or tissue of an embryo in early development, or the parts derived from this, which include the epidermis and nerve tissue
the innermost layer of cells or tissue of an embryo in early development, or the parts derived from this, which include the lining of the gut and associated structures.
the rudimentary alimentary cavity of an embryo at the gastrula stage
2 germ layer; having a body derived from only two embryonic cell layers (ectoderm and endoderm, but no mesoderm), as in sponges
the middle layer of an embryo in early development, between the endoderm and ectoderm; 3 germ layers
having a body derived from three embryonic cell layers (ectoderm, mesoderm, and endoderm), as in all multicellular animals except sponges and coelenterates.
Fluid sealed place; any fluid-filled space in a multicellular organism, other than those of vessels. However, the term usually refers to the space located between an animal’s outer covering, and the outer lining of the gut cavity, where internal organs develop
the body cavity in metazoans, located between the intestinal canal and the body wall.
An animal that lacks a coelom. Acoelomates, which include the flatworm, fluke, tapeworm, and ribbon worm, exhibit bilateral symmetry
a multicellular organism whose mouth develops from a primary embryonic opening, such as an annelid, mollusk, or arthropod.
Radial cleavage can be divided at 4 cell stage, are undeterminate get 2 individuals
this group includes annelids, mollusks; this form of cleavage can vary between species, but generally the first two cell divisions result in four blastomeres
2 flagellum most are unicellular, reinforced plates of cellulose, spin through the water
Determinate is the form of cleavage in most protostomes. It results in the developmental fate of the cells being set early in the embryo development. Each cell produced by early embryonic cleavage does not have the capacity to develop into a complete embryo.
occurs when a coelom is formed by splitting the mesodermal embryonic tissue.
the opening of the central cavity of an embryo in the early stage of development.
an animal lacking a backbone, such as an arthropod, mollusk, annelid, coelenterate, etc. The invertebrates constitute an artificial division of the animal kingdom, comprising 95 percent of animal species and about 30 different phyla.
a primitive sedentary aquatic invertebrate with a soft porous body that is typically supported by a framework of fibers or calcareous or glassy spicules. Sponges draw in a current of water to extract nutrients and oxygen.
f an organism, e.g., a barnacle) fixed in one place; immobile. suspension feeder
the large, central cavity of sponges. Water enters the spongocoel through hundreds of tiny pores and exits through the larger opening. Depending on the body plan of the sponge, the spongocoel could be a simple interior space of the sponge or a complexly branched inner structure.
a large aperture in a sponge through which water is expelled.
of or denoting a person, animal, or plant having both male and female sex organs or other sexual characteristics. most sponges are hermaphroditic
antiobiotic producing structure produced by strep, can be used against strep that resists penicillin
flagellated cell with a collar of protoplasm at the base of the flagellum, numbers of which line the internal chambers of sponges.
any invertebrate animal, as a hydra, jellyfish, sea anemone, or coral, considered as belonging to the phylum Cnidaria, characterized by the specialized stinging structures in the tentacles surrounding the mouth; a coelenterate.
an explosive cell containing one giant secretory organelle or cnida that defines the phylum Cnidaria. Cnidae are used for prey capture and defense from predators.
functions in both digestion and the distribution of nutrients and particles to all parts of the body.
a specialized cell in the tentacles of a jellyfish or other coelenterate, containing a barbed or venomous coiled thread that can be projected in self-defense or to capture prey.
a taxonomic class of individually very small, predatory animals, some solitary and some colonial, most living in saltwater. eg. portuguese man of war
free-swimming marine coelenterates having a gelatinous medusoid stage as the dominant phase of its life cycle
a solitary or colonial sedentary form of a coelenterate such as a sea anemone, typically having a columnar body with the mouth uppermost surrounded by a ring of tentacles. In some species, polyps are a phase in the life cycle that alternates with a medusoid phase
a free-swimming sexual form of a coelenterate such as a jellyfish, typically having an umbrella-shaped body with stinging tentacles around the edge. In some species, medusae are a phase in the life cycle that alternates with a polypoid phase.
any of various highly venomous jellyfishes of the Australian tropical waters, having a cuboidal body with tentacles
Any of a class (Anthozoa) of marine organisms, such as the corals and sea anemones, that have radial segments and grow singly or in colonies.
Any of various parasitic and nonparasitic worms of the phylum Platyhelminthes, such as a tapeworm or a planarian, characteristically having a soft, flat, bilaterally symmetrical body and no body cavity.
a phylum of relatively simple bilaterian, unsegmented, soft-bodied invertebrates.
one of the traditional sub-divisions of the phylum Platyhelminthes, and include all the sub-groups that are not exclusively parasitic. There are about 4,500 species, which range from 1 mm to 600 mm in length
small parasitic flatworms mainly found on skin or gills of fish
parasites of molluscs and vertebrates. Most trematodes have a complex life cycle with at least two hosts. The primary host, where the flukes sexually reproduce, is a vertebrate. The intermediate host, which is the agent of dispersal, is usually a snail.
a parasitic flatworm, the adult of which lives in the intestine of humans and other vertebrates. It has a long ribbonlike body with many segments that can become independent, and a small head bearing hooks andsuckers.
the name given to a class of parasitic flatworms, commonly called tapeworms, of the phylum Platyhelminthes.
the anterior end of a tapeworm, bearing suckers and hooks for attachment.Origin
each segment in the strobila of a tapeworm, containing a complete sexually mature reproductive system.
a minute multicellular aquatic animal
the whole passage along which food passes through the body from mouth to anus. It includes the esophagus, stomach, and intestines.
reproduction from an ovum without fertilization, esp. as a normal process in some invertebrates and lower plants.
horseshoe-shaped structure bearing ciliated tentacles around the mouth in certain small marine invertebrates.
sessile mossy aquatic animal having the anus of the polyp outside the crown of tentacles
hermaphrodite wormlike animal living in mud of the sea bottom
marine animals that have hard "valves" on the upper and lower
surfaces, unlike the left and right arrangement in bivalve molluscs.
a ribbon worm.
muscular appendage found in mollusks. While most mammals have two or four feet, mollusks have one
One of the three main parts of a mollusc, containing most of the internal organs.
) a fold of skin enclosing the viscera and secreting the substance that produces the shell.
the cavity between the mantle and the body proper of a mollusk or brachiopod in which the respiratory organs lie
one of the oldest groups of eukaryotic algae, and also one of the largest, with about 5,000–6,000 species of mostly multicellular, marine algae, including many notable seaweeds.
(in a mollusk) a rasplike structure of tiny teeth used for scraping food particles off a surface and drawing them into the mouth
A trochophore is a type of free-swimming planktonic marine larva with several bands of cilia.By moving their cilia rapidly, a water eddy is created. In this way they control the direction of their movement.
a marine mollusk that has an oval flattened body with a shell of overlapping plates.
an order comprising the chitons all of which have the foot occupying the whole ventral surface of the body and the shell composed of eight calcified dorsal plates
more commonly known as snails and slugs, are a large taxonomic class within the phylum Mollusca. The class Gastropoda includes snails and slugs of all kinds and all sizes from microscopic to large.
the spontaneous twisting of the visceral hump through 180° during larval development.
an aquatic mollusk that has a compressed body enclosed within a hinged shell, such as oysters, clams, mussels, and scallops.
an active predatory mollusk of the large class Cephalopoda, such as an octopus or squid.
a segmented worm such as an earthworm or leech
an annelid worm such as an earthworm.
a polyphyletic class of annelid worms, generally marine. Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made of chitin.
an aquatic or terrestrial annelid worm with suckers at both ends. Many species are bloodsucking parasites, esp. of vertebrates, and others are predators.
a worm of the large phylum Nematoda, such as a roundworm or threadworm.
an invertebrate animal of the large phylum Arthropoda, such as an insect, spider, or crustacean.
an extinct marine arthropod that occurred abundantly during the Paleozoic era, with a carapace over the forepart, and a segmented hind part divided longitudinally into three lobes.
a rigid external covering for the body in some invertebrate animals, esp. arthropods, providing both support and protection.
of an animal) shed old feathers, hair, or skin, or an old shell, to make way for a new growth.
open circulatory system
a system in which a fluid in a cavity called the hemocoel bathes the organs directly with oxygen and nutrients and there is no distinction between blood and interstitial fluid; this combined fluid is called hemolymph or haemolymph.
constitutes one of the major subdivisions of the phylum Arthropoda, and includes horseshoe crabs, scorpions, spiders, mites, harvestmen, ticks
anarthropod of a group that includes the centipedes, millipedes, and related animals. Myriapods have elongated bodies with numerous leg-bearing segments.Origin
an animal having six feet
an arthropod of the large, mainly aquatic group Crustacea, such as a crab, lobster, shrimp, or barnacle.
either of a pair of appendages in front of the mouth in arachnids and some other arthropods, usually modified as pincerlike claws.
an extinct marine arthropod of a group occurring in the Paleozoic era. They are related to horseshoe crabs and resemble large scorpions with a terminal pair of paddle-shaped swimming appendages.
(in a spider or other arachnid) each of a pair of respiratory organs composed of many fine leaves. They are situated in the abdomen and have openings on the underside.
the jaw or a jawbone, esp. the lower jawbone in mammals and fishes.
: from 405 million to 345 million years ago; preponderance of fishes and appearance of amphibians and ammonites
is the mode of development of certain insects that includes three distinct stages: the egg, nymph, and the adult stage, or imago. These groups go through gradual changes; there is no pupal stage
is a term applied to insect groups to describe the specific kind of insect development which includes four life stages – as an embryo or egg, a larva, a pupa and an imago or adult
the name for an order of peracarid crustaceans, including familiar animals such as woodlice and pill bugs.
a small shrimplike planktonic crustacean of the open seas. It is eaten by a number of larger animals, notably the baleen whales.Origin
a phylum of marine animals. The adults are recognizable by their radial symmetry, and include such well-known animals as starfish, sea urchins, sand dollars, and sea cucumbers.
an animal of the large phylum Chordata, comprising the vertebrates together with the sea squirts and lancelets.
water vascular system
a network of water vessels in the body, the tube feet being operated by hydraulic pressure within the vessels.
arge number of small, flexible, hollow appendages protruding through the ambulacra, used either for locomotion or for collecting food and operated by hydraulic pressure within the water-vascular system.
an animal of a large group distinguished by the possession of a backbone or spinal column, including mammals, birds, reptiles, amphibians, and fishes
a cartilaginous skeletal rod supporting the body in all embryonic and some adult chordate animals.Origin
Pharyngeal slits are filter-feeding organs found in non-vertebrate chordates and hemichordates living in aquatic environments.
a marine invertebrate of a group that includes the sea squirts and salps. They have a rubbery or hard outer coat and two siphons to draw water into and out of the body.
each of a number of body segments containing the same internal structures, clearly visible in invertebrates such as earthworms but also present in the embryonic stages of vertebrates.Origin
an animal that possesses a skull.
Neural crest cells are a transient, multipotent, migratory cell population unique to vertebrates that gives rise to a diverse cell lineage
an extinct marine animal of the Cambrian to Triassic periods, having a long wormlike body, numerous small teeth, and a pair of eyes. It is now believed to be the earliest vertebrate.
lateral line system
the lateral line is a system of sense organs found in aquatic vertebrates, chiefly fish, used to detect movement and vibration in the surrounding water
an extinct fish of the Devonian period, having the front part of the body encased in broad flat bony plates.Origin
a small spiny-finned, jawed fossil fish of a group found chiefly in the Devonian period.Origin
are jawed fish with paired fins, paired nares, scales, a heart with its chambers in series, and skeletons made of cartilage rather than bone.
A spiral valve is the lower portion of the intestine of some sharks, rays, skates and bichirs. A modification of the ileum, the spiral valve is internally twisted or coiled to increase the surface area of the intestine, to increase nutrient absorption.
producing young by means of eggs that are hatched after they have been laid by the parent.
producing young by means of eggs that are hatched within the body of the parent, as in some snakes.
) bringing forth live young that have developed inside the body of the parent.
a common cavity at the end of the digestive tract for the release of both excretory and genital products in vertebrates (except most mammals) and certain invertebrates. Specifically, the cloaca is present in birds, reptiles, amphibians, most fish, and monotremes.
a structure that closes or covers an aperture, in particular.
a gas-filled sac present in the body of many bony fishes, used to maintain and control buoyancy.
any of the tissues, derived from the fertilized egg, that enclose or otherwise contribute to the support of the developing embryo, as the yolk sac, allantois, amnion, and chorion.
a reptile of a large group characterized by the presence of two temporal openings in the skull, including the lizards, snakes, crocodiles, dinosaurs, and pterosaurs.
any of the mostly large, flightless birds with a ratite breastbone, i.e., the ostrich, rhea, emu, cassowary, and kiwi, together with the extinct moa and elephant bird.Origin
a fossil reptile of a Permian and Triassic group, the members of which show increasingly mammalian characteristics and include the ancestors of mammals.
the concept that evolutionary change takes place in some body parts or systems without simultaneous changes in other parts. Another definition is the "evolution of characters at various rates both within and between species"