Term
|
Definition
has a single origin = eucaryotic cell complex enough that probably arose only once.
•
unicellular or multicellular
•
variation in cell covering
•
variation in feeding mode |
|
|
Term
| Where did the nucleus and endoplasmic reticulum (ER) arose? |
|
Definition
| The nucleus and endoplasmic reticulum arose from infoldings of prokaryotic cell membrane |
|
|
Term
| Where did many organelles evolved? |
|
Definition
| Many organelles evolved via endosymbiosis between an ancestral eukaryote and a bacterial cell |
|
|
Term
| Describe the Mitochondria |
|
Definition
| Aerobic bacteria engulfed by larger bacteria |
|
|
Term
| Describe the Chloroplasts |
|
Definition
| Larger bacteria engulfed smaller photosynthetic bacteria |
|
|
Term
| What did the endosymbiosis hypothesis support? |
|
Definition
–
DNA inside mitochondria and chloroplasts
•
DNA similar to bacteria DNA in size and character
–
Ribosomesinside mitochondria similar to bacterial ribosomes
–
Chloroplasts and mitochondria replicate by binary fission –not mitosis |
|
|
Term
| What's the difference between eukaryotics? |
|
Definition
| -presence of a cytoskeleton-Compartmentalization (nucleus & organelles) |
|
|
Term
| Describe the cell surface of Protists |
|
Definition
–
Plasma membrane
–
Extracellular material (ECM) in some
•
Diatoms –Silica shells |
|
|
Term
|
Definition
–
Dormant cell with resistant outer covering
–
Used for disease transmission |
|
|
Term
| Name some characteristics of Protists |
|
Definition
Locomotion
–
Flagella
•
One or more
–
Cilia
•
Shorter and more numerous than flagella
–
Pseudopodia (“false feet”)
•
Lobopods –large, blunt
•
Filopods –thin, branching
•
Axopods –thin, long |
|
|
Term
| What kind of reproduction does protists use? |
|
Definition
Asexual and sexual
Asexual reproduction
–
Typical mode of reproduction
–
Some species have an unusual mitosis
•
Mitosis –equal size daughter cells
•
Budding –one daughter cell smaller
•
Schizogony–cell division preceded by several nuclear divisions; produces several individuals
Sexual reproduction
–
May be obligate, or only under stress
–
Meiosis is a major eukaryote innovation
–
Union of haploid gametes produced by meiosis
–
Advantage in allowing frequent genetic recombination |
|
|
Term
| Name a Animal-like protist |
|
Definition
|
|
Term
| Name a plant-like protist |
|
Definition
| Algae (red, green, brown) |
|
|
Term
| Name a fungus-like protist |
|
Definition
|
|
Term
| Describe animal-like protists? |
|
Definition
Unicellular–made up of one cell
•
Classified by how they move
•
Heterotrophs–they eat other organisms or dead organic matter |
|
|
Term
|
Definition
No cell wall
•
Moving using pseudopods-plasma extensions
•
Engulf bits of food by flowing around & over them
•
Amoebas are paraphyletic |
|
|
Term
|
Definition
•Heterotrophic marine
Complex life cycles with haploid & diploid generations |
|
|
Term
|
Definition
Glassy exoskeletons made of silica
Needlelike pseudopods |
|
|
Term
| Describe the flagellates: the motoboats |
|
Definition
Use a whip-like extension called a flagella to move
Some cause Disease
Diseases like Trichonmnas foetus: cat & cow disease
Trichomnoas vaginalis: Human STD
Giardia duodenalis |
|
|
Term
|
Definition
Live in termite guts
–
Host cellulose degrading bacteria
•
Trichomonas vaginalis –STD
•
Undulating membrane for locomotion
•
Use flagella
•
Lack mitochondria –derived trait |
|
|
Term
|
Definition
the hairy ones
Mover beating tiny hairs called cilia
Conjugation-only different mating types can conjugate |
|
|
Term
|
Definition
the parasite
Non-motile-Do not move
Live inside a host
One type causes malaria
Pneumonia in aids patients |
|
|
Term
|
Definition
| Found in the intestines of arthropods, annelids, and mollusks |
|
|
Term
| What is toxoplasma gondii |
|
Definition
Causes infections in humans with immunosuppression
Can cross placental barrier to harm fetus |
|
|
Term
| Describe in detail plant like protist and name them |
|
Definition
•Multicellular-made of more than one cell
•Photosynthetic-make their own food
•No roots, stems, or leaves
•Each has chlorophylland other photosynthetic pigments
Euglenoids, Dinoflagellates, Diatoms, Red, Brown, & Green Algae |
|
|
Term
|
Definition
The survivors
•Aquatic-unicellular
•Move around like animals (2 anterior flagella)
Can ingest food from surroundings when light is not available
•some with Chloroplastsome without
•no sexual reproduction
•Move towards the light = Stigma |
|
|
Term
|
Definition
The Golden Ones
Phyla: Bacillariophyta/Chrysophyta
•shells made of silica (glass)
•unicellular or chains
•Photosynethic pigments called carotenoids-give them their golden color
•some move by using two long groves, called raphes. |
|
|
Term
|
Definition
the spinning ones
•Spin around using two flagella
•Responsible for Red Tides
•Unicellular or colonial
•Create toxins that can kill animals & sometimes people |
|
|
Term
|
Definition
(Rhodophyta)
•Seaweeds (microscopic to very large)
•Multicellular, marine organisms
•Have accessory pigments (red & blue)
•
Lack flagella & centrioles |
|
|
Term
|
Definition
(Phaeophyta)
•Life cycle involves alternation of generations
-
Sporophyte-multicellularand diploid
-
Gametopyte-multicellularand haploid
•They have air bladders to help them float at the surface |
|
|
Term
|
Definition
(Chlorophyta)
•Most live in fresh water
•Can be unicellular or multicellular
•Live alone or in groups called colonies |
|
|
Term
| Describe Fungus- like Protists? |
|
Definition
All form delicate, netlike structures on the surface of their food source
•Obtain energy by decomposing organic material
•Live in cool moist, shady places where they grow on damp, organic matter |
|
|
Term
| What is the Phyla of fungus-like protists? |
|
Definition
Plasmodium slime molds
Cellular slime molds
Water Molds & Downy Mildews |
|
|
Term
| Describe Plasmodium slime molds |
|
Definition
•Stream along as a plasmodium
•Ingest bacteria and other organic material
•Form reproductive structures when surroundings dry up
•Form plasmodium: a mass of cytoplasm that contains many diploid nuclei but
no cell walls or membranes-its feeding stage
•Huge, single-celled, multinucleate, oozing masses
•Creeps by amoeboid movement-2.5 cm/hour
•Spores are dispersed by the wind and grow into new plasmodium |
|
|
Term
| What a cellular slime molds |
|
Definition
•In feeding mode, they exist as individual amoebic cells
•When food becomes scare, they come together with thousands of their own kind to reproduce
•Single cells combine & differentiate, creating an early model of multicellularity
•Important group for the study of cell differentiation because of their relatively simple developmental systems.
•Individual organisms behave as separate amoebas
•When food is scarce, organisms aggregate to form a slug |
|
|
Term
| What are water molds & downy mildews |
|
Definition
•Live in water or moist places on land
•Feed on dead organisms or parasitize plants
•Fuzzy white growths.
•Undergo sexual reproduction
•Motile zoospores with 2 unequal flagella (produced asexually) |
|
|
Term
| What was phytophthora infestans |
|
Definition
-Irish potato famine (1845-1847)
-400,000 people died |
|
|
Term
|
Definition
•“creates more variation” Is this valid or necessary?
•allows more individuals to survive a disease (mutant survival vs. recessives)
•Allows, through crossover, combination of bad genes and elimination. (bad genes often do bad things, not just inoperative)
•Bigger cells, smaller population, mutation not enough |
|
|
Term
| What happens in basic sexual divison -meiosis |
|
Definition
0. chromosomes make copies of selves –stay connected
1.Chromosomes line up in pairs = diploid
organism with two sets of information
2. Division 1 = pairs split
3. Pairs line up and split –
4 result –4 gametes (eggs or sperm)each haploid –have all information but only one set.
5. Gametes meet, get back to diploid fertilized egg.
You now have “sex” = 2 gametes come together |
|
|
Term
|
Definition
|
|
Term
| eucaryptic advances over bacteria |
|
Definition
•Larger size
•Cytoskeleton
•Nucleus
•Diploid –linear chromosomes
•Mitosis (like bacteria except for pattern
•Meiosis –new
•Organelles; mitochondria, chloroplasts
•Loss of cell wall –thinner outer membrane.
•Living in oxygen atmosphere = protected from damaging uv light |
|
|
Term
| What are the general features of animals |
|
Definition
•Heterotrophy
•Multicellularity
•Tissues
•Active movement
•No cell walls
•Diversity in form
•Diversity in habitat
•Sexual reproduction
•Embryonic development |
|
|
Term
|
Definition
| all animals are heterotrophs (they obtain there energy & organic molecules by ingesting other organisms). |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
| consume both autotrophs& heterotrophs |
|
|
Term
|
Definition
| consume decomposing organisms |
|
|
Term
| Explain why animals have no cell walls? |
|
Definition
| quite flexible, many cells of animal bodies are held together by extracellular structural proteins such as collagen |
|
|
Term
| Explain sexual reproduction in animals |
|
Definition
•cells form in meiosis function as gametes
•haploid cells do not divide by mitosis 1st(rather fuse directly to form the zygote) |
|
|
Term
| Explain Embryonic Development |
|
Definition
•zygote undergoes mitotic divisions(cleavage)
•embryos of most kinds of animals develop into larva |
|
|
Term
| Explain Embryonic Development |
|
Definition
•zygote undergoes mitotic divisions(cleavage)
•embryos of most kinds of animals develop into larva |
|
|
Term
|
Definition
•cells organized into structural & functional units (except in sponges)
•collection of cells that together are specialized to perform specific task.
•Animals unique to have 2 tissues associated with movement
•Muscle tissues contract
•Nervous tissues conduct signals |
|
|
Term
| What are the five transitions can be noted in animal evolution? |
|
Definition
•Tissues
•Symmetry
•Body cavity
•Development
•Segmentation |
|
|
Term
| Describe the evolution of tissues in animals? |
|
Definition
-Parazoa(Sponges –the simplest animals) lack defined tissues & organs
-Have the ability to disaggregate & aggregate their cells
-Eumetazoa(all other animals) have distinct and well-defined tissues
-Have irreversible differentiation for most cell types |
|
|
Term
| Describe the Evolution of symmetry |
|
Definition
Sponges lack definite symmetry
-Eumetazoa have a symmetry defined along an imaginary axis drawn through the animal’s body
-There are two main types of symmetry |
|
|
Term
| What are the advantages that a bilaterally symmeterical animals has over a radical |
|
Definition
1. Cephalization-Evolution of a definite brain area
2. Greater mobility |
|
|
Term
| Describe the evolution of body cavity? |
|
Definition
Eumetazoa produce three germ layers
-Outer ectoderm(body coverings & nervous system)
-Middle mesoderm(skeleton & muscles)
-Inner endoderm(digestive organs & intestines) |
|
|
Term
| What is the Bilaterian pattern of development? |
|
Definition
-Mitotic cell divisions of the egg form a hollow ball of cells, called the blastula-
Blastula indents to form a two-layer-thick ball with:
-Blastopore= Opening to outside-
Archenteron= Primitive body cavity |
|
|
Term
|
Definition
| Protostomesdevelop the mouth first from or near the blastopore-Anus (if present) develops either from blastoporeor another region of embryo |
|
|
Term
|
Definition
the anus first from the blastopore
Mouth develops later from another region of the embryo |
|
|
Term
| how do deuterostomes differ from protostomes? |
|
Definition
1. Cleavage pattern of embryonic cells
-Protostomes= Spiral cleavage
-Deuterostomes= Radial cleavage
2. Developmental fate of cells
-Protostomes= Determinate development
-Deuterostomes= Indeterminate development
3. Origination of coelom
•
Protostomes = Forms directly from the mesoderm
•
Deuterostomes = Forms indirectly from the archenteron |
|
|
Term
| Who evolved first? Deuterostomes or protostomes |
|
Definition
| Deuterostomes evolved from protostomes more than 500 MYA |
|
|
Term
| What is the evolution of segmentation |
|
Definition
| -Segmentation provides two advantages 1. Allows redundant organ systems in adults such as occurs in the annelids2. Allows for more efficient and flexible movement because each segment can move independently |
|
|
Term
| What are the two main branches Metazoans are divided into? |
|
Definition
-Parazoa= Lack symmetry and tissues
-Eumetazoa= Have symmetry and tissues
-Diploblastic= Have two germ layers
-Triploblastic= Have three germ layers |
|
|
Term
|
Definition
marine animals that are parasites of echinoderms
-Have no body cavity and only incomplete segmentation(have been allied with annelids) |
|
|
Term
| What is molecular systematics |
|
Definition
| uses unique sequences within certain genes to identify clusters of related groups |
|
|
Term
| Name the Division of the protostome group? |
|
Definition
Ecdysozoaand Spiralia
-The latter is then broken down into Lophotrochozoa and Platyzoa |
|
|
Term
| Name the two evolutionary developmental hypothesis? |
|
Definition
1.The multinucleate hypothesis
2.The colonial flagellate hypothesis
1.The multinucleate hypothesis2.The colonial flagellate hypothesisMolecular systematicsusing rRNAsequences settles this argument in favor of the colonial flagellate hypothesis |
|
|
Term
| Explain the Cambrian explosion |
|
Definition
-The homeobox(Hox) developmental gene complex evolved
-Provided a tool that can produce rapid changes in body plan |
|
|
Term
|
Definition
•Parazoa (Sponges)
–lacking tissues (and therefore organs)
–Most lack symmetry
–Adults sessile, larval free-swimming
–Little coordination among cells
–Larval sponges free-swimming
–Asexual (fragmentation) & sexual reproduction |
|
|
Term
| What are the cell types of porifera? |
|
Definition
–Truly multicellular
–3 functional layers in “vase” |
|
|
Term
|
Definition
•Animals with distinct tissues
•Embryos have distinct layers
–Gastrodermis develops from endodermis
–epidermis and nervous system develop from ectoderm
–Middle mesoderm (only in bilateral animals) forms the muscles
•True body symmetry
–Radial symmetry
–Bilateral symmetry |
|
|
Term
|
Definition
•Most marine, few fresh water species
•Diploblastic
•Carnivorous
•Bodies have distinct tissues but no organs
–No reproductive, circulatory, or excretory systems
•No concentrated nervous system
–Latticework of nerve cells
–Touch, gravity, light receptors |
|
|
Term
| How do Cniadarians capture prey? |
|
Definition
Cnidarians use nematocysts to capture prey
–Secreted within nematocyte
–Mechanism of discharge unknown
–Some carry venom |
|
|
Term
| What are the two basic body forms of Cnidarians? |
|
Definition
–Polyps –cylindrical and sessile
–Medusa –umbrella-shaped and free-living |
|
|
Term
| Describe the Body of Phylum Cnidaria |
|
Definition
Body plan has single opening leading to gastrovascularcavity
–Site of digestion
–Most gas exchange
–Waste discharge
–Formation of gametes in many
•2 layers to body wall
1.Epidermis
2.Gastrodermis
–Mesoglea between layers |
|
|
Term
| What is the gastrovascular space in cnidaria |
|
Definition
Gastrovascularspace also serves as hydrostatic skeleton
–Provides a rigid structure against which muscles can operate
–Gives the animal shape |
|
|
Term
| What do polyp speices build? |
|
Definition
an exoskeleton of chitin or calcium carbonate around themselves
–Some build an internal skeleton |
|
|
Term
| Describe the Cnidaria life cycle |
|
Definition
Some cnidarians occur only as polyps, & others exist only as medusae, (many alternate between these 2phases)
•Both phases consist of diploid individuals
In general, in species having both polyp & medusa in the life cycle, the medusa forms gametes |
|
|
Term
| How does digestion occur in Phylum Cnidaria? |
|
Definition
Major evolutionary innovation in cnidarians is extracellular digestion of food inside the animal
–Digestion takes place partly in gastrovascularcavity
–Cells then engulf fragments by phagocytosis |
|
|
Term
|
Definition
4 or 5 classes
-Sea anemones, most corals, sea fans
-Solitary and colonial polyps-
Symbiotic dinoflagellates(zooxanthellae) photosynthesize& provide nutrients to reef coral
-Coral reefs economically important |
|
|
Term
|
Definition
–Box jellies
–Strong swimmers, voracious fish predators
–Stings may be fatal to humans |
|
|
Term
|
Definition
–Hydroids, Hydra, Portuguese man-of-war
–Both polyp and medusa stages
–Only class with freshwater members |
|
|
Term
|
Definition
–Jellyfish
–Medusa more conspicuous and complex
–Ring of muscle cells allows for rhythmic contractions for propulsion |
|
|
Term
|
Definition
–Star jellies
–Resembles a medusa in most ways but is attached to the substratum by a sort of stalk that emerges from the side opposite the mouth |
|
|
Term
| Describe the Phlum Ctenophora? |
|
Definition
16(comb jellies, sea walnuts, or sea gooseberries)
•8 rows of comblike plates of fused cilia that beat in a coordinated fashion
•Many bioluminescent
•2 tentacles covered with colloblasts
–Discharge strong adhesive used to capture prey
•Phylogenetic position unclear |
|
|
Term
| What are the Bilaterian Acoelomates? |
|
Definition
Characterized by bilateral symmetry
•Allowed for high levels of specialization
•Bilaterians are traditionally classified by the condition of their coelom
–Acoelomates
–Pseudocoelomates
–Coelomates |
|
|
Term
| What are Phylum Platyhelminthes? |
|
Definition
Flatworms are ciliated, soft-bodied animals
•Bodies are solid aside from an incomplete digestive cavity
•Many species are parasitic
•Others are free-living
–Marine, freshwater, moist terrestrial |
|
|
Term
| Explain the excretory & osmoregulatory systems that the flatwarm has?? |
|
Definition
Have an excretory & osmoregulatory system
–Network of fine tubules runs through body
–Flame cells located on the side branches
•Flagella move water and excretory substances into the tubules and then to pores located between the epidermal cells through which the liquid is expelled
–Metabolic wastes are excreted into the gut and eliminated through the mouth |
|
|
Term
| Explain the nervous system in a flatwarm |
|
Definition
–Anterior cerebral ganglion and nerve cords
–Eyespot can distinguish light from dark |
|
|
Term
| Describe the reproduction system in a flatworm? |
|
Definition
–Most are hermaphroditic
–Undergo sexual reproduction
–Also have capacity for asexual regeneration |
|
|
Term
| What are the two major groups in Platyheliminthes? |
|
Definition
–Free-living Turbellaria
•Probably not monophyletic
•Dugesia–common planarian in bio labs
–Parasitic Neodermata
•Trematoda–flukes
–Attach within host body by suckers, anchors, or hooks
–Life cycle may have 2 or more hosts
–Clonorchissinensis, oriental liver fluke
•Cercomeromorpha–tapeworms |
|
|
Term
| What is the most important trematodes to human health? |
|
Definition
blood flukes Schistosoma
Afflict 5% of world’s population
About 800,000 people die each year from schistosomiasis or bilharzia
Fertilized egg must break through the wall of the blood vessels in intestine or the urinary bladder to get out |
|
|
Term
| What is Cercomermomorpha? |
|
Definition
tapeworms
Adult hangs onto inner wall of host intestine using scolex |
|
|
Term
| Describe the body of a tapeworm? |
|
Definition
proglottids
Complete hermaphroditic unit, containing both male and female reproductive organs
–Formed continuously |
|
|
Term
| What is a "beef tapeworm"? |
|
Definition
Taenia saginata
–Frequent human parasite
–From eating uninspected rare beef |
|
|
Term
| What is Phylum Acoelomorpha? |
|
Definition
•Acoel flatworms were once considered basal members of the phylum Platyhelminthes
•Have a primitive nervous system and lack a digestive cavity
•Based on molecular evidence, similarities are convergent |
|
|
Term
| What is the Phlum Cycliophora? |
|
Definition
Discovery reported in 1995
•Striking circular mouth surrounded by a ring of cilia
•Anatomy and life cycle are very unusual
•Live on the mouthparts of claw lobsters on both sides of the North Atlantic |
|
|
Term
| What are Pseudocoelomates? |
|
Definition
•Pseudocoelom –cavity that lies between tissues derived from the mesoderm and those derived from the endoderm
•Pseudocoelomic fluid performs the functions carried out by a circulatory system in most coelomate animals
•Not monophyletic |
|
|
Term
|
Definition
•Vinegar eels, eelworms, and other roundworms
•Members of this phylum are found everywhere –abundant and diverse
•Marine, freshwater, parasites, free-living |
|
|
Term
| What is the symmetrical of a nematoda? |
|
Definition
Bilaterally symmetrical and unsegmented
•Covered by a flexible, thick cuticle that is molted as they grow |
|
|
Term
| Does a Nematoda have a digestive system if do explain? |
|
Definition
Digestive system well developed
–Stylets–piercing organs near mouth
–Pharynx –creates sucking action
–Anus |
|
|
Term
| What is the sexual reproduction in nematoda? |
|
Definition
–Most gonochoric
–Sexual dimorphism –male smaller with hooked end
–Internal fertilization
–Indirect development –egg, larva, adult |
|
|
Term
|
Definition
| –Adults consist of a fixed number of cells |
|
|
Term
| What is the lifestyle of a nematoda? |
|
Definition
Many are active hunters, preying on protists and other small animals
–Others are parasites of plants
–Still others live within the bodies of larger animals |
|
|
Term
|
Definition
causes human diseases
–Common in southern U.S.
–Produce anemia |
|
|
Term
|
Definition
causes trichinosis
–Forms cysts in muscles
–Infection from eating undercooked meat |
|
|
Term
|
Definition
Pinworms
–Infects 30% of children in U.S.
–Causes itching of the anus |
|
|
Term
| What is Ascaris Lumbricoides? |
|
Definition
intestinal roundworm
–Infects 1 in 6 worldwide
–Adult female can be 30 cm long
–Rare in areas with modern plumbing |
|
|
Term
| Name some Serious tropical nematode diseases? |
|
Definition
–Filariasis
–Elephantiasis |
|
|
Term
| Describe the Phylum Mollusca? |
|
Definition
•Second in diversity only to arthropods
•Include snails, slugs, clams, octopuses and others
•Some have a shell, some do not |
|
|
Term
| What was the impacts of zebra mussel invasion? |
|
Definition
•clog water & drain pipes at municipal water supplies & at industries
•displaced native freshwater mussels of the area
•increase water clarity allows light to penetrate further, potentially promoting macrophyte populations
US $5 billon in control efforts |
|
|
Term
| Describe the Mollusk Body Plan |
|
Definition
•Mantle
–Thick epidermal sheet
–Bounds mantle cavity
–Secrete shell (if there is one)
•Foot
Primary means of locomotion for many
Divided into arms or tentacles in cephalopods |
|
|
Term
| Describe the internal organs of the mollusca? |
|
Definition
–Coelom is highly reduced
•Limited to small spaces around the excretory organs, heart, and part of the intestine
–Digestive, excretory, and reproductive organs are concentrated in a visceral mass |
|
|
Term
|
Definition
gills in aquatic mollusks
•Also filter food in most bivalves |
|
|
Term
| Describe the shell of a mollusca |
|
Definition
–Protects against predators & adverse environments
–Secreted by outer surface of mantle
–Clearly not essential –repeated loss or reduction
–Typical shell has 2 layers of calcium carbonate |
|
|
Term
|
Definition
–Rasping, tongue like structure used in feeding
–Used to scrape up algae
–In predatory gastropods, modified to drill through clam shells
–In Conus snails, modifies into harpoon with venom gland
-Bivalves do not have a radula
•Gills used in filter feeding |
|
|
Term
| Describe the nitrogenous waste removal |
|
Definition
nephridia
–Consist of cilia-lined openings called nephrostomes
–Tube to excretory pore to mantle cavity |
|
|
Term
| Describe the circulatory system in Mollusca? |
|
Definition
–Open circulatory system
•Hemolymph sloshes around hemocoel
•3-chambered heart
–Cephalopods have a closed circulatory system |
|
|
Term
| Describe the Mollusk reproduction system? |
|
Definition
•Most mollusks are gonochoric
–A few are hermaphroditic
–Some oysters change sex
•Most engage in external fertilization
–Gastropods have internal fertilization
•Mollusk zygote undergoes spiral cleavage |
|
|
Term
|
Definition
| –Free-swimming larval stage |
|
|
Term
|
Definition
–2ndfree-swimming larval stage
–Only in bivalves and most marine snails |
|
|
Term
| Name the classes of mollusks? |
|
Definition
1.Polyplacophora–chitons
2. Gastropoda–limpets, snails, slugs
3. Bivalvia–clams, oysters, scallops
4. Cephalopoda–squids, octopuses, cuttlefishes, and chambered nautilus |
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Term
| Describe Class Polyplacophora? |
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Definition
(Chitons)
•Marine mollusks that have oval bodies
•8 overlapping dorsal calcareous plates
•Body is not segmented under the plates
•Most chitons are grazing herbivores |
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Term
| Describe the Class Gastropoda? |
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Definition
•Limpets, snails, slugs
•Primarily marine –some freshwater, & only terrestrial mollusks
•Most have a single shell –some lost it
•Typically have pairs of tentacles with eyes
•Torsion
•Torsion should not be confused with coiling
•Coiling –Spiral winding of the shell |
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Term
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Definition
(SEA SLUGS)
–Exposed gills
–active predators
–Many secrete distasteful chemicals
–Some extract nematocysts from cnidarian prey and transfer them to their body surface |
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Term
| Describe the Class Bivalvia? (Bivalves) |
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Definition
•Includes clams, scallops, mussels, oysters, and others
•Most marine, some freshwater
•No radulaor distinct head
•Have 2 shells (valves) hinged together
•Water enters through inhalant siphon and exits through exhalant siphon |
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Term
| Describe of Class Cephalopoda |
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Definition
•Active marine predators
•Only mollusk with closed circulatory system
•Foot has evolved into a series of arms equipped with suction cups
–Beak-like jaws, toxic saliva
•Largest relative brain sizes among invertebrates
•Highly developed nervous system
•Living cephalopods lack external shell
–Except chambered nautilus
–Squid and cuttlefish have internal shells
•Jet propulsion using siphon
•Ink can be ejected from siphon
•Chromatophores allow for changing skin color for camouflage or communication |
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Term
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Definition
(Ribbon Worms)
•Most are marine; a few species live in fresh water and humid terrestrial habitats
•Body plan resembles a flatworm
•Has a complete gut
•Rhynchocoel–fluid filled coleomiccavity
•Gonochoric with sexual reproduction
–Asexual reproduction through fragmentation
•Belong to lophotrochozoans because
–Blood flows entirely in vessels
–Rhynchocoel |
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Term
| What is the Phylum Annelida? |
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Definition
•Segmented worms
•Body built of repeated units
•Allows for specialization
•May not be monophyletic |
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Term
| Describe the body plan of a Annelida? |
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Definition
•Body plan
–Head has well-developed cerebral ganglion
–Sensory organs in ring like segments
–Many species have eyes
–Segments divided internally by septa
•Each segment has a pair of excretory organs, a ganglion, and locomotory structure
–Closed circulatory system
–Ventral nerve cord
•Each part of digestive tract specialized for different function
•Locomotion
•Closed circulatory system
–Gas exchange by diffusion across body surfaces
•Excretory system –nephridialike mollusks |
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Term
| What are 2 classes of Phylum Annelida? |
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Definition
1.Class Polychaeta
–Monophylynot well established
2. Class Clitella
–Oligochaeta
–Hirudinea(includes leaches) |
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Term
| Describe the Class Polychaeta? |
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Definition
(Polychaetes)
•Include clamworms, scaleworms, sea mice, tubeworms
•Have paired parapodiaon most segments
–Used in locomotion or gas exchange
–Chaetae on parapodia
•Most gonochoric
–External fertilization
–Trochophorelarva |
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Term
| What are deep-sea tubeworm (Riftia) |
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Definition
–Adults gutless
–Sulfur-oxidizing bacteria synthesize organic compounds used by worm
–Found near hydrothermal vents |
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Term
| Describe the Class Cilitellata |
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Definition
•Clitellum found in all members
•Earthworms
–Head not well differentiated
–No parapodia
–Few chaetae project from body wall
–Hermaphroditic but cross-fertilize
–Clitellum secretes mucus cocoon |
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Term
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Definition
class Cilellata
–Occur mostly in freshwater
–Usually flattened dorsoventrally
–Hermaphroditic and cross-fertilization
•Clitellum develops only during breeding season
–Coleom reduced, not divided into segments
–Suckers at both ends of body
–No chaetae (except for one species)
–Some eat detritus, others suck blood |
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Term
| Describe the Lophophorates? |
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Definition
•Include two phyla of mostly marine animals
–Bryozoa and Brachiopoda
•Both characterized by lophophore
–Circular or U-shaped ridge around the mouth with 1–2 rows of ciliated tentacles
–Functions in gas exchange and feeding
–May be convergent evolution
•Phylogeny a puzzle |
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Term
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Definition
| "moss animals” •Bryozoans are small and live in colonies •Their anus opens near their mouth •Asexual reproduction occurs frequently by budding •Individuals secrete a tiny chitinous chamber called a zoecium attached to substrate –May deposit calcium carbonate (formed reefs in past) |
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Term
| Describe Phylum Brachinopoda? |
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Definition
(lamp shells)
•Have two calcified shells
–Dorsal and ventral (not lateral as in bivalves)
–Lophophorelies on the body, between the shells
•Phoronidswere once a separate phylum
–Each individual secretes a chitinoustube
–Extends lophophoreto feed |
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Term
| Describe the phlyum Arthropoda? |
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Definition
•By far the most successful animals
–Well over 1,000,000 species (2/3 of all named species)
•Arthropods affect all aspects of human life
•Divided into four extant classes
–Chelicerates, crustaceans, hexapods, and myriapods |
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Term
| What is the Arthropod Morphology? |
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Definition
•Part of arthropod success explained by
1.Segmentation
•In some classes specialized into tagmata
–Head, thorax, abdomen
–Head and thorax may be fused into cephalothorax or prosoma
2.Exoskeleton
•Made of chitin and protein
•Protects against water loss
•Must undergo ecdysis –molting |
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Term
| Explain jointed appendages? |
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Definition
•May be modified into antennae, mouthparts, or wings
•Can be extended and retracted |
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Term
| Describe the circulatory and nervous system of a arthropoda? |
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Definition
•Open circulatory system
•Nervous system
–Double chain of segmented ganglia
–Ventral ganglia control most activities
•Can eat, move, or copulate with brain removed |
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Term
| Describe compounded eyes found on many arthropods |
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Definition
–Composed of independent visual units called ommatidia
•Other arthropods have simple eyes, or ocelli
–May be in addition to compound eyes
–Have single lenses
–Distinguish light from darkness |
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Term
| Describe the respiratory system in arthropoda? |
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Definition
–Many marine arthropods have gills
–Some tiny arthropods lack any structure for gas exchange
–Terrestrial arthropods use tracheae
•Branch into tracheoles in direct contact with cells
•Connected to the exterior by spiracles
–Valves control water loss
–Many spiders use book lungs
•Leaflike plates |
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Term
| Describe the Excretory system in Arthropoda? |
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Definition
–In aquatic arthropods much of the waste diffuses out of gills
–Terrestrial insects and some others use Malpighiantubules
•Eliminates nitrogenous wastes as concentrated uric acid or guanine
•Efficient conservation of water |
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Term
| Describe the Class Cehlicerata? |
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Definition
Spiders, ticks, mites, scorpions, daddy long-legs, horseshoe crabs, sea spiders
•Most anterior appendages called chelicerae
–May function as fangs or pincers
•Body divided into 2 tagmata
–Anterior prosomabearing all appendages
•Pedipalpsand 4 pairs of walking legs
–Posterior opisthosomacontains reproductive organs |
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Term
|
Definition
(spiders)
•Particularly important as predators
•Many spiders catch their prey in silk webs
•Other spiders actively hunt their prey
•All spiders have poison glands with channels through their chelicerae |
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Term
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Definition
(mites and ticks)
•Most diverse of the chelicerates
•Predators and parasites
•Most mites are small
–Cephalothorax and abdomen are fused into an unsegmented ovoid body
•Ticks are larger
–Blood-suckers
•Can carry many diseases
–Rocky Mountain spotted fever, Lyme disease |
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Term
| Describe the Class Crustacea? |
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Definition
•Largely marine, some freshwater
•Crabs, shrimps, lobsters, barnacles, crayfish, copepods, pill bugs, sand fleas
•Have three tagmata
–Cephalon and thorax fused to form a cephalothorax
•2 pairs of antennae, 3 pairs of appendages for chewing, and various pairs of legs
–Most appendages are biramous
•Gas exchange through gills or across cuticle |
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Term
| What is the body plan for a Crustaceas? |
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Definition
•All crustacthe oceans about 545 MYA
–Mouth at one end, fin at the othereans but barnacles are gonochoric
•Many kinds of copulation
•Naupliusstage
–Several stages before maturity
–Evidence of common ancestor for diverse group |
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Term
| What is a Decapod Crustaceans? |
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Definition
–Shrimps, lobsters, crabs, and crayfish
–Have 10 feet –5 pairs of thoracic appendages
–Exoskeleton usually enforced with CaCO3
–Cephalothoraxcovered by carapace
–Lobsters and crayfish
–Crab has small abdomen held under carapace |
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Term
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Definition
(Barnacles)
•Sessile as adults
•Captures food with feathery legs
•Hermaphroditic |
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Term
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Definition
•Insects are by far the largest group of animals
–Number of species and number of individuals
•More than half of all named animal species
•Approximately one billion billion (10^18) insects are alive at any one time
•Three body regions
1.Head
2.Thorax has three segments, each with a pair of legs
•May have one or two pairs of wings –outgrowths of body wall
3.Abdomen
•Most insects have compound eyes |
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Term
| Class Hexapoda internal organization? |
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Definition
–The digestive tract is a tube
–Digestion takes place in stomach (midgut)
–Excretion tales place through Malpighian tubules
–Winged insects have dilated tracheae forming air sacs
•Form bellows to force air deep into body
–Some parasitic or aquatic forms have permanently closed spiracles –use diffusion |
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Term
| What are sensory receptors in Hexapodas? |
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Definition
•Sensory setae are hairlikestructures
•Detect chemical and mechanical signals
•Tympanum –a thin membrane associated with tracheal air sacs
•Pheromones also used for communication
•Mating signals, trail markers |
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Term
| Explain the Insect life histories |
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Definition
–Many insects undergo metamorphosis
–Simple metamorphosis (grasshoppers)
•Immature stages similar to adults
–Complete metamorphosis (butterflies)
•Immature larva are wormlike
•A resting stage, pupa or chrysalis, precedes the final molt into adult form |
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Term
| Describe the Class Myriapoda? |
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Definition
Centipedes (subclass Chilopoda)
–One pair of appendages per segment
–Carnivorous –poison fangs
•Millipedes (subclass Diplopoda)
–Two pairs of appendages per segment
•Each segment is a tagmaof 2 segments
–Herbivores
–Complex glands produce bad-smelling fluid in defense
•Head regions followed by numerous segments
•Gonochoric, internal fertilization, lay eggs
–Young add segments as they grow |
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Term
| Describe the Phlyum Echinodermata |
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Definition
•Exclusively marine
•Deuterostomeswith an endoskeleton
•Pentaradialsymmetry
•Sea stars, brittle stars, sea urchins, sand dollars, sea cucumbers
Thought to have evolved from bilaterally symmetrical ancestors because larvae are bilaterally symmetrical |
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Term
| Describe the symmetry in Echinodermata |
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Definition
–Pentaradialas adult, bilateral as larva
–Oral surface defines mouth
–All systems organized with branches radiating from center
–Nervous system is nerve ring with branches |
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Term
| Describe the Endoskeleton in Echinodermata |
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Definition
–Epidermis covers endoskeleton
–Composed of calcium carbonate ossicles
–May be tightly or loosely joined
–All members have mutable collagenoustissue |
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Term
| What is the water-vascular system in Echinodermata? |
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Definition
–Radial canal extends from ring canal into each body branch
–Water enters through madreporite
–Flows through stone canal to ring canal |
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Term
|
Definition
may or may not have suckers
•Ampulla–muscular sac at base
•Used in movement, feeding, gas exchange |
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Term
| What is regeneration relating to the phylum Echinodermata |
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Definition
–Many able to regenerate lost parts
–Some reproduce asexually by splitting |
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Term
| How does reproduction work in Echinodermata? |
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Definition
Most reproduction is sexual
–Gonochoric
–Gametes released into water
–Free-swimming larvae
–Each class has a characteristic type of larva |
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Term
| Describe the 5 extant classes |
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Definition
1.Asteroidea(sea stars and sea daisies)
–Important predators in many marine systems
–Most have 5 arms, some have multiples of 5
2.Echinoidea(sea urchins & sand dollars)
–Lack arms
–Double rows of tube feet
–Protective moveable spines
3.Ophiuroidea (brittle stars)
–Largest class
–Arms are equal diameter their entire length
–Arms are easily autotomized
4.Crinoidea (sea lilies and feather stars)
5.Holothuroidea (sea cucumbers) |
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Term
| What is the Phylum Chordata |
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Definition
Fishes, amphibians, reptiles, birds, and mammals
•Chordates are deuterostome coelomates
•Nearest relatives are echinoderms (the only other deuterostomes) |
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Term
| What are the 4 features of Chordata? |
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Definition
1.Nerve cord
2.Notochord
–May be replaced by vertebral column
3.Pharyngeal slits
–Pharyngeal pouches present in all vertebrate embryos
4.Postanal tail |
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Term
| Describe the Chordate muscles |
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Definition
are arranged in segmented blocks called somites
Most chordates have an internal skeleton against which the muscles work |
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Term
| What are Phylum Chordata subphyla? |
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Definition
1. Urochordata
2. Cephalochordata
Nonvertebrates
3. Vertebrata |
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Term
| What is Subphylum Urochordata? |
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Definition
•Tunicates & salps are marine animals
•Larvae are tadpolelike & have notochord and nerve cord
–Are free-swimming but do not feed
•Adults typically lose the tail and notochord
–Are immobile filter-feeders
–Many secrete a tunic (cellulose sac) that surrounds the animal |
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Term
| What is Subphylum Cephalochordata? |
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Definition
•Lancelets are scaleless chordates
•Notochord persists throughout animal’s life
•Spend most of their time partly buried
•No distinguishable head
•Feed on plankton using cilia-generated currents
•Closest relatives to vertebrates |
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Term
| What is Subphylum Vertebrata? |
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Definition
•Vertebrates = chordates with a spinal column
•Distinguished from nonvertebrates by
–Vertebral column –Encloses and protects the dorsal nerve cord
–Head–Distinct and well-differentiated possessing sensory organs
Vertebrates also have:
•Neural crest –unique group of embryonic cells that forms many vertebrate structures •Internal organs –liver, kidneys, endocrine glands, heart, and closed circulatory system•Endoskeleton–made of cartilage or bone–Makes possible great size and extraordinary movement |
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Term
| When did the first vertebrates appear? |
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Definition
the oceans about 545 MYA
–Mouth at one end, fin at the other
•Jawed fishes soon became dominant
•Amphibians invaded the land
•Reptiles replaced them as the dominant land vertebrates
•Birds and mammals became dominant after Cretaceous mass extinction |
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Term
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Definition
| Most diverse vertebrate group•Over half of all vertebrates•Provided the evolutionary base for invasion of land by amphibians |
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Term
| Describe the actual characteristics of fishes? |
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Definition
1.Vertebral column (Hagfish & lamprey exceptions)
2.Jaws and paired appendages
•Hagfish and lamprey exceptions
3.Internal gills
4.Single-loop blood circulation
5.Nutritional deficiencies
•Inability has been inherited by all their vertebrate descendants |
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Term
| What is the history of the fishes? |
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Definition
•The first fishes had mouths with no jaws
–Agnatha extant as hagfish and lampreys
–Ostracoderms are now extinct
Jaws later evolved from the anterior gill arches that were made of cartilage |
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Term
| Describe the jaws in fishes? |
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Definition
Armored fishes and spiny fishes both had jaws (both extinct)
–Spiny fish were common during early Devonian –replacing ostracoderms
•Cartilage skeleton (skin had small plates of bone)
–Placoderms became common in late Devonian
•Jaw more improved than spiny fishes’
–Upper jaw fused to the skull and the skull hinged on the shoulder |
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Term
| What the Class Chondrichthyes |
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Definition
| •Sharks, skates, rays•Became the dominant sea predators in the Carboniferous period (360–280 MYA)•Cartilage skeleton “calcified”with granules of calcium carbonate–Light, strong skeleton |
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Term
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Definition
•Sharks were among the first vertebrates to develop teeth
–Evolved from rough scales on mouth’s skin
–Easily lost but continuously replaced
•Sharks (and bony fishes) have a fully developed lateral line system |
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Term
| Describe the reproduction system in sharks |
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Definition
•Eggs are fertilized internally
•Most pups are born alive
A few species do lay fertilized eggs
•Sharks have long gestation periods and relatively few offspring
–Therefore, are not able to recover quickly from population declines |
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Term
| Describe the evolved of bony fishes? |
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Definition
•Evolved at the same time as sharks about 400 MYA
–but, they have an internal skeleton made of bone |
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Term
| Describe the Swim bladder? |
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Definition
| –Gas-filled sac that allows bony fishes to regulate their buoyant density |
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Term
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Definition
–Hard plate, the operculum, covers gills
–Flexing plate permits water pumping over gills |
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Term
| What are the Ray-finned fishes? |
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Definition
(class Actinopterygii)
–Parallel bony rays support and stiffen each fin
–No muscles in the fins |
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Term
| What are the Lobe-finned fishes? |
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Definition
(class Sarcopterygii)
–Have paired fins that consist of a long fleshy muscular lobe
–Supported by central core of bones with fully articulated joints
–Almost certainly the amphibian ancestors |
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Term
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Definition
5 distinguishing amphibian features
1.Legs –adaptation to life on land
2.Lungs
3.Cutaneous respiration –supplement lungs
4.Pulmonary veins –separate pulmonary circuit allows higher pressure blood to tissues
5.Partially divided heart –improves separation of pulmonary and systemic circuits |
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Term
| What are the successful invasion of land by vertebrates required adaptations? |
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Definition
–Legs to support body’s weight
–Lungs to extract oxygen from air
–Redesigned heart & circulatory system to drive larger muscles
–Reproduction still in water to prevent egg drying
–System to prevent whole body desiccation |
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Term
| How did amphibians evolved? |
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Definition
from lobe-finned fish
Sturdy forelegs, flipper-shaped hindlimbs
Overlapping ribs form solid cage for lungs & heart |
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Term
| What is transitional fossil: Tiktaalik? |
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Definition
| heart25Shoulder, forearm, & wrist bones like amphibians, but at the end of the limb was a lobed fin, rather than the toes of an amphibian |
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Term
| What are the 3 modern Amphibian groups? |
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Definition
•Order Anura (“without tail”)
•Order Caudata (“visible tail”)
•Order Apoda (“without legs”) |
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Term
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Definition
(frogs & toads)
Frogs have smooth, moist skin & long legs
–Most live in or near water, aquatic tadpole stage before metamorphosis into adult
•Toads have bumpy, dry skin and short legs
–Most live in dry environments•Eggs laid in water
–lack watertight membranes–Eggs fertilized externally
–Tadpole –swimming larval form
–Gradual metamorphosis into adult form |
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Term
|
Definition
Have long bodies, tails, and smooth, moist skin
Live in moist places
Eggs are fertilized internally –sperm packet
Larvae similar to adults |
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Term
| Order Apoda? (caecilians) |
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Definition
Tropical, burrowing amphibians
Legless with small eyes and jaws with teeth
Fertilization is internal |
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Term
| Describe the reptiles characeteristics |
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Definition
–Internal fertilization
•Sperm fertilizes egg before protective membranes are formed
–Improved circulation
•Oxygen is provided to the body more efficiently
•Septum in heart extended to create partial wall
–Crocodiles, birds, and mammals have completely divided 4-chambered heart |
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Term
| All living reptiles are ectothermic? What does that mean |
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Definition
–Obtain heat from external sources
–Regulate body temperature by moving in and out of sunlight |
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Term
| What are the four surviving orders of reptiles? |
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Definition
–Chelonia (turtles and tortoises)
–Rhynchocephalia (tuataras)
–Squamata (lizards and snakes)
–Crocodylia (crocodiles and alligators) |
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Term
| What are the order chelonia? |
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Definition
•Differ from all other reptiles because their bodies are encased within a protective shell
•Tortoises are terrestrial while turtles are mostly aquatic
•Both lack teeth but have sharp beaks
•Marine turtles must return to land to lay eggs |
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Term
| What is Order Rhynchocephalia? |
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Definition
•Contains only two species of tuataras
•Large, lizardlike animals about half a meter long
•Only found on islands near New Zealand
•Parietal eye
–Eye with lens and retina concealed under layer of scales on top of head |
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Term
| What are the order squamata? |
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Definition
•A characteristic of this order is the presence of paired copulatory organs in the male
•Snakes –3000 species
–Lack limbs, movable eyelids, and external ears
•Lizards –3800 species
–Many have ability to regenerate lost tails |
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Term
|
Definition
•25 species of large, primarily aquatic carnivorous reptiles
•Crocodiles
–Typically nocturnal
–Tropical and subtropical regions
•Alligators –only 2 species
•Bodies well adapted to stealth hunting
–Eyes on top of head, nostrils on top of snout, enormous mouth, strong necks
•Crocodiles resemble birds far more than they do other living reptiles
–Build nests and care for their young
–Have a 4-chambered heart |
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Term
|
Definition
Birds are the most diverse of all terrestrial vertebratesSuccess lies in unique structure –feather Birds exhibit 3 evolutionary novelties
1.Feathers
2.Hollow bones
3.Physiological mechanisms for flight |
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Term
| What are the different traits of birds? |
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Definition
Birds still retain many reptilian traits
–Amniotic eggs and scales on legs
–Lack teeth and tails of reptiles
•Two major distinguishing traits
–Feathers
•Modified scales of keratin
•Provide lift for flight and conserve heat
–Flight skeleton
•Bones are thin and hollow
•Many are fused for rigidity –anchor strong flight muscles
•Feathers developed from reptile scales
•Linked structures provide continuous surface and a sturdy but flexible shape |
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Term
| What are the first bird known? |
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Definition
•Archaeopteryxis the first known bird
–Had skull with teeth, long reptilian tail
–Feathers on wings and tail
–Forelimbs nearly identical to those of theropods
•Feather probably evolved for insulation
•Most paleontologists agree that birds are the direct descendants of theropod dinosaurs |
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Term
|
Definition
•28 orders of birds
–Most ancient birds are flightless –like ostrich
–Ducks, geese, and waterfowl next
–Passeriformes comprise 60% of species today |
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Term
| What are the adaptations for flight? |
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Definition
1.Efficient respiration
•Air passes all the way through lungs in a single direction
2.Efficient circulation
•4-chambered heart so muscles receive fully oxygenated blood
•Rapid heartbeat
3.Endothermy
•Body temperature (40–42oC) permits higher metabolic rate |
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Term
| What is the Class Mammalia? |
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Definition
2 fundamentally mammalian traits
1.Hair
•Long, keratin-rich filaments that extend from hair follicles
•Insulation, camouflage, sensory structure
2.Mammary glands
•Females possess mammary glands that secrete milk |
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Term
|
Definition
Endothermy depends on higher metabolic rate
•4-chambered heart
•Respiration using diaphragm |
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Term
|
Definition
in most mammals
•Specialized organ that brings fetal and maternal blood into close contact |
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Term
| What are specialized teeth? |
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Definition
–teeth are highly specialized to match particular eating habits
–Contrast carnivore teeth to herbivore teeth |
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Term
| Describe the digestion of plants? |
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Definition
| –Herbivorous mammals rely on mutualistic partnerships with bacteria for cellulose breakdown |
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Term
| What is the development of hooves and horns? |
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Definition
–Hooves are specialized keratin pads
–Horns are bone surrounded by keratin
–Antlers are made of bone, not keratin |
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Term
|
Definition
Bats
–Only mammals capable of powered flight
–Wing is a leathery membrane of skin and muscle stretched over 4 finger bones
–Navigate in the dark by echolocation |
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Term
| Describe the History of Mammals? |
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Definition
•Mammals have been around since the time of the dinosaurs, about 220 MYA
–Tiny, shrewlike, insect-eating, tree-dwelling creatures
–May have been nocturnal –large eye sockets
•Mammals reached their maximum diversity in the Tertiary period (65–2 MYA)
–After mass extinction of dinosaurs
–Decline in the total number of mammalian species over last 15 million years |
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Term
| What are the 2 subclasses of Mammals |
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Definition
1.Prototheria (most primitive)
–Lay shelled eggs
–Only living group is the monotremes
2.Theria
–Viviparous –young are born alive
–Two living groups
•Marsupials or pouched mammals
•Placental mammals |
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Term
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Definition
| Lay shelled eggs•Like reptiles have single opening (cloaca) for feces, urine, and reproduction•Lack well developed nipples•Only three living species–Duck-billed platypus–2 echidna species |
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Term
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Definition
•Major difference is pattern of embryonic development
–Short-lived placenta
–After birth, it crawls into marsupial pouch, latches onto nipple, and continues to develop
•Kangaroo –isolation of Australia
•Opossum –only North American marsupial |
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Term
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Definition
•Has a true placenta that nourishes embryo throughout its development
•Includes most living mammals |
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Term
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Definition
•Primates are the mammals that gave rise to our own species
•Evolved two features that allowed them to succeed in an arboreal environment
1.Grasping fingers and toes
•First digit (thumb) is opposable in many
2.Binocular vision
•Eyes are shifted toward the front of the face
•Lets brain judge distances precisely |
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Term
| Describe the two earliest primates grouP? |
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Definition
1.Prosimians
–Only a few survive today
–Lemurs, lorises and tarsiers
–Large eyes with increased visual acuity
–Most are nocturnal
2.Anthropoids
–Include monkeys, apes, and humans
–Almost all diurnal
•Changes in eye design include color vision
–Expanded brain
–Live in groups with complex social interactions
•Care for young for extended period
•Long period of learning and brain development |
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Term
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Definition
•30 MYA
–New World monkeys migrated to South America
•All arboreal; many have prehensile tail
–Old World monkeys and hominids remained in Africa
•No prehensile tails |
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Term
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Definition
–Apes
•Gibbon, orangutan, gorilla, and chimpanzee
•Larger brains than monkeys and lack tails
–Hominids
•Humans
•Soon after the gorilla lineage diverged, the common ancestor of all hominids split off from the chimpanzee line to begin the evolutionary journey leading to humans |
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Term
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Definition
•The common ancestor of apes & hominids is thought to have been an arboreal climber
–Hominids became bipedal, walking upright
–Apes evolved knuckle-walking
•Differences related to bipedal locomotion
–Human vertebral column is more curved
–Spinal cord exits from bottom of skull
–Humans carry much of the body’s weight on the lower limbs |
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Term
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Definition
•Genus Homo
–3–7 species (depending)
•Genus Australopithecus
–7 species
–Older and smaller-brained
•Several even older lineages
•In every case where the fossils allow a determination, the hominids are bipedal, the hallmark of hominid evolution |
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Term
| What are Australopithecines? |
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Definition
•Our knowledge is based on hundreds of fossils found in Africa
•Characteristics
–Weighed about 18 kg
–About 1 m tall
–Hominid dentition
–Brains no larger than those of apes
–Walked upright |
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Term
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Definition
•Seems to have evolved as australopithecines left forests for grasslands and open woodland
•African fossils demonstrate that bipedalism extended back 4 MYA
•Substantial brain expansion, on the other hand, did not appear until about 2 MYA
•Why bipedalism evolved is still a matter of controversy |
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Term
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Definition
•The first humans evolved from australopithecine ancestors about 2 MYA
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•In the 1960s, hominid bones were found near stone tools in Africa
–Early human was called Homo habilis
–It closely resembled Australopithecus, but had larger brain |
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Term
| What is Homo foresiensis? |
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Definition
•In 2004, a new human species was discovered in the tiny Indonesian Island of Flores
•Youngest fossils only 15,000 years old!
•H. floresiensis had a diminutive stature
•Believed to be more closely-related to H. erectusthan to H. sapiens |
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Term
| What are the modern Humans? |
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Definition
•Modern humans first appeared in Africa about 600,000 years ago
•Three species are thought to have evolved
–Homo heidelbergensis (oldest)
•Coexisted with H. erectus
–Homo neanderthalensis
•Shorter and stockier than modern humans
–Homo sapiens (“wise man”)
•Some lump all 3 into H. sapiens |
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Term
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Definition
Homo neanderthalensis
–Made diverse tools
–Took care of sick and buried dead
–First evidence of symbolic thinking
–They abruptly disappeared about 34,000 years ago
•Suddenly replaced by Cro-Magnons
–2 species did not interbreed
–Complex social organization
–Elaborate cave paintings
–Thought to have had full language capabilities |
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Term
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Definition
•Only surviving hominid
•Progressive increase in brain size
–Effective making and use of tools
–Refined and extended conceptual thought
–Use of symbolic language
•Extensive cultural experience
–We change and mold our world rather than change evolutionarily in response to the environment |
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