Ch. 18 The Evolution of Animal Diversity Flashcards
Animalia
The kingdom that contains the animals
Blastula
An embryonic stage that marks the end of cleavage during animal development; a hallow ball of cells in many species
Gastrula
The embryonic stage resulting from gastrulation in animal development; most animals have gastrula made up of 3 layers of cells (ectoderm, endoderm, mesoderm)
Larva
An immature individual that is structurally and often ecologically very different from an adult
Metamorphosis
The transformation of a larva into an adult
From where did the animal kingdom probably originate?
Colonial protists
Invertebrate
Animal that lacks a backbone
Porifera
The phylum that contains the sponges, characterized by choanocytes, a porous body wall, and no true tissues
Sponge
Marine or freshwater, living singly or clusters by budding (regeneration)
Radial Symmetry
An arrangement of the body parts of an organism like pieces of a pie around an imaginary central axis; any slice passing longitudinally through a radially symmetrical organism’s central axis divides it into mirror-image halves
What are the 3 layers of a sponge (porifera)?
1) Flattened cells w/ pink pore
2) Amoebocytes
3) Choanocyte
Amoebocytes
An amoeba-like cell that moves by pseudopodia found in most animals; may digest and distribute food, dispose of wastes, make skeleton, fight infections, change into other cell types
Choanocytes
A flagellated feeding cell found in sponges also called a collar cell, it has a collar like ring that traps food particles around the base of its flagellum
Choanoflagellate
An ancestral colonial protist from which sponges, and possibly all animals, probably arose (bottom of ponds/shallow sea)
Cnidaria
The phylum that contains the hydras, jelly fishes, sea anemones, corals, and related animals characterized by enidocytes, radial symmetry, a gastrovascular cavity, polyps, and medusae
- can have both polyp and medusa
Polyp
One of two types of cnidarian body forms; a columnar, hydra-like body (stationary)
Medusa
One of two body types of cnidarian body forms; an umbrella-like body form aka jellyfish (free moving)
Gastrovascular cavity
A digestive compartment w/ a single opening, the mouth; may function in circulation, body support, waste disposal, gas exchange, and digestion
Cnidocytes
A specialized cell for which the phylum Cnidaria is named; consists of a capsule containing a fine thread, which, when discharged, functions in defense and prey capture
What are the 7 characteristics of an anima?
1) Eukaryotic
2) Multicellular
3) Heterotrophic
4) Lack cell walls
5) Ingestion (internal digestion)
6) Unique intercellular junctions
7) Embryonic stages (gametes -> zygote -> blastula -> gastrula)
What are the criteria of classification?
1) Symmetry
- radial or bilateral
2) Level of organization
- tissue level or organ system level
3) Embryonic Tissue
4) Body plan
- gastrovascular cavity or complete digestive system
5) Body Cavity
- pseudocoelom or coelom
Symmetry
How body parts are arranged around a median plane
Body Cavity
Fluid filled space b/w digestive tract
Pseudocoelom
A body cavity that is in direct contact with the wall of the digestive tract and muscle layer
- Lacks mesoderm
Coelom
A body cavity completely lined w/ mesoderm and extends from body wall and wraps around digestive tract
- There is mesoderm so more flexible to grow and independently
- flexible, organs may grow/move independently, prevents internal injury
What are the 9 phyla of Animalia?
Invertebrates…
1) Porifera
2) Cnidaria
3) Platyhelminthes
4) Nematoda
5) Mollusca
6) Annelida
7) Arthropoda
8) Echinodermata
Vertebrae…
9) Chordata
What are the 6 classes of vertebraes?
1) Agnatha
2) Fish
3) Amphibians
4) Reptilian
5) Aves
6) Mammalia
Agnatha
Jawless fish w/ suction cap mouth and sharp teeth (parasitic
A class of vertebrate animals that are superficially fishlike but lack jaws and paired fins
Fish
Jawed vertebrates w/ gills and paired fins
- chrondrichthyes or Osteichthyes
Chrondrichthyes
Cartilaginous
- sharks, rays, “living fossils”
- actue senses, strong jaws (detect electrical fields and water pressure)
- can’t stop swimming (can’t pump water)
- poor vision
- lateral line system
Osteichthyes
Bony (bony fish)
- tuna, salmon, trout
- operculum (protective flap for gills)
- swim bladder for buoyancy in water
- ray fins
- ray finned fish or lobe finned fish
Amphibians
Live on land, chained to water
- newt, salamander
- moist skin, young are tad poles w/ gills, external fertilization, jelly like sperm (why water)
- metamorphosis (tadpole -> frog)
Tadpole vs Frog
Tadpole is a legless taled aquatic algae eater w/ gills
Frog is a 4 legged, tailless, and terrestrial insect eater
Reptilian
Do not require water
- drier skin w/ scales, amniotic egg, internal fertilization
- ectothermic
- snakes, lizards, turtles, alligators
Aves
A class of vertebrate animals that consists of the birds
- reptilian ancestry
- adapted body for flight (hollow beak/bones, short stubby tale, breath muscles)
- endothermic
- elongated scales into feathers
Mammalia
A class of vertebrae that consists of mammals
- Evolved from reptiles, nocturnal, long before dinosaurs
- endothermic
- hair, fur, live birth, internal development, mammory glands
What are 4 unique features of mammalia?
1) hair + fur
2) live birth
3) internal development
4) mammory glands
What does “ontogeny recapitulates phylogeny” mean?
All animals exhibit features that reflect their evolutionary feature
What are the 3 groups of mammalia?
1) Monotremes
2) Marsupials
3) eutherians/placental
Bilateral symmetry
An arrangement of body parts such that an organism can be divided equally by a single cut passing longitudinally through it; has mirror-image right and left
Anterior
Pertaining to the front/head of a bilaterally symmetrical animal
Posterior
Pertaining to the rear/tail of a bilaterally symmetrical animal
Dorsal
Pertaining to the back of a bilaterally symmetrical animal
Ventral
Pertaining to the underside/bottom of a bilaterally symmetrical animal
Lateral
Pertaining to the side of a bilaterally symmetrical animal
Platyhelminthes
The phylum that contains the flatworms, the bilateral animals w/ a thin/flat body form, gastrovascular cavity or no digestive system, and no body cavity; the free living flatworms, flukes, and tapeworms
Flatworms
A member of the phylum Platyhelminthes
- free living flatworms, fluke, tapeworms
Free living flatworms
Planarian w/ head w/ 2 large eyespots and flap at each side to detect chemicals and simple brain
- cilia + muscles
Fluke
One group of parasitic flatworms
- copulate freely = produce thousands eggs a day
- blood flukes cause schistosomiasis
Tapeworms
A Parasitic flatworm characterized by the absence of a digestive tract and a repeating ribbonlike body
Nemotoda
The phylum that contains the roundworms or nematodes; characterized by a pseudocoelom, a cylindrical, wormlike, body form, and a tough cuticle
Roundworm
A member of the phylum Nematoda
Cuticle
In animals, a tough, nonliving outer layers of the skin. In plants, a waxy coating on the surface of stems and leaves that help retain water.
Mollusca
The phylum that contains the mollusks; characterized by a muscular foot, mantle cavity, and radula
- gastropods, bivalves, cephalopods
Mantle
In a mollusk, the outgrowth of the body surface that drapes over the animal; produces the shell and forms the mantle cavity
Function: respiration, waste disposal, sensory reception, house a gill for oxygen extraction and dispose of liquid waste
Radula
A toothed, rasping organ used to scrap up or shred food; found in many mollusks
What are the 3 cavities of coelom?
1) Heart
2) Reproductive Organs
3) Kidney
Gastropods
A member of the largest group of mollusks.
- snails/slugs
- freshwater, sea water, terrestrial
- ones on land have a mantle cavity developed into lung
Bivalves
A member of mollusks that includes clams, mussels, scallops, oysters
- shells divided into 2 halves hinged together
- sedentary (sand/mud)
Cephalopod
A member of a group of mollusks that includes squids/octopus
- built for speed/agility
- heavy/large shells, some small/internal shells or altogether missing
- marine predators w/ beaklike jaws and radula
- large brains, sophisticated sense organs
Body Segmentation
Subdivision along the length of an animal body into a series of repeated parts called segments
- body flexibility/mobility
Annelida
The phylum that contains the segmented worms, or annelids characterized by uniform segmentation
- includes earthworms, polychaetes, and leeches
- distinct head/tail w/ similar body segments
- sea, freshwater, damp soil habitats
- mainly bottom dwelling scavengers
Earthworms
Extracts nutrients as soil passes through digestive tube
- undigested go thru anus and feces actually improves soil texture
Polychaetes
Largest group, segmented appendages and hard bristles that increase surface area for oxygen and dispose waste
- marine living in tubes and extend appendages to trap food
Leeches
Blood sucking habits, free living organisms for small invertebrate
- fresh water, terrestrial species inhabit moist vegetation in tropics
- used for bloodletting
Arthropods
The most diverse phylum in the animal kingdom; characterized by chitinous exoskeleton, molting, jointed appendages, and body formed of distinct segments
- horseshoe crab, arachnids, crustaceans, millipedes, centipedes, and insects
- evolved from annelids (or ancestor)
Exoskeleton
Hard, external skeleton that protects an animal and provides points of attachment for muscles
- layers of chitin mixed with protein
Molting
In arthropods, the process of shedding an old exoskeleton and secreting a new, larger one
Horseshoe crab
“living fossil” w/ little change
Arachnids
A member of a major arthropod group that includes spiders, scorpions, ticks, mites
Crustaceans
A member of a major arthropod group that includes lobsters, crayfish, crabs, shrimps, and barnacles
Millipedes
Wormlike landlubbers that eat decaying plant matter (2 pairs of legs per segment)
Centipedes
Terrestrial carnivores w/ poisonous claws and one pair of legs for each segment
Incomplete metamorphosis
The transformation of young/larvae into adults that are similar to the young except in size/body proportions
- orthoptera, odonata, hemiptera
Complete metamorphosis
The transformation of a larva into an adult that looks very different, and often functions very differently in its environment, than the larva
- coleoptera, lepidoptera, diptera, hymenoptera
What are the 7 common orders of insects?
1) Orthoptera
- have biting/chewing mouthparts and herbivorous
2) Odonata
- 2 pairs of similar wings and biting mouthpart (carnivorous)
3) Hemiptera
- true bugs, piercing/sucking mouthparts, 2 pairs of wings
4) Coleoptera
- beetles, occur everywhere, biting/chewing mouthpart, carnivorous/herbivores/omnivores, 2 pairs of wings
5) Lepidoptera
- moth/butterfly, 2 pairs of wings covered by scales, mouthpart is a long drinking tube that coils
6) Diptera
- flies, single pairs of wings, small/club shaped organs (halteres) for maintaining balance, lapping mouthparts
7) Hymenoptera
- 2 pairs of wings, narrow waist (ants, bees, wasps)
Echinodermata
The phylum of echinoderms, including sea stars, sea urchins, and sand dollars; characterized by a rough or spiny skin, a water vascular system, an endoskeleton, and radial symmetry in adults
Endoskeleton
A hard skeleton located w/in the soft tissues of an animal; includes spicules of sponges, the hard plates of echinoderms, and the cartilage and body skeletons of many vertebrae
Water vascular system
In echinoderms, a radially arranged system of water filled canals that branch into extensions called tube feet; the system provides movement & circulates water, facilitating gas exchange and waste disposal
Chordata
The phylum of the chordates; characterized by a dorsal hollow nerve cord, a notochord, gill structures, and a post anal tail
- lancelets, tunicates, and vertebrates
What are 4 distinct features of chordata?
1) Dorsal hollow nerve cord
2) Notochord
3) Gill structures
4) Post anal tail
Notochord
A flexible, cartilage-like, longitudinal rod located b/w the digestive tract and nerve cord in chordate animals; present only in embryos of many species
Vertebrate
In chordate animal w/ a backbone
Invertebrate
An animal that lacks a backbone
Tunicates
One group of invertebrate chordates; stationary, saclike, large gill apparatus
- common on coral reefs, rocks, boats
Lancelets
One group of invertebrate chordates; feed on suspended particles; exhibit the four features, segmented muscles
- closest living relative to vertebrates
- paedomorphosis (key to evolution)
Cartilaginous fishes
flexible skeleton made of cartilage
Lateral line system
A row of sensory organs along each side of a fish’s body; sensitive to changes in water pressure, it enables a fish to detect minor vibrations in the water
Bony fish
Stiff skeleton reinforced by hard calcium salts
Operculum
A protective flap on each side of a fish’s head that covers a chamber housing the girls (allows breathing w/o swimming)
Swim bladder
A gas filled internal sac that helps body fish maintain buoyancy
Ray finned fish
A bony fish having fins supported by thin flexible skeletal rays; all but one species of body fish are rayfin
Lobe finned fish
A bony fish w/ strong muscular fins supported by long extinct except for coelacanth
Amniotic Egg
A shelled egg in which an embryo develops w/in a fluid-filled amniotic sac and is nourished by yolk; produces by reptiles, birds, and egg laying mammals, it enables them to complete their life cycles on dry land
Ectothermic
An animal that warms itself mainly by absorbing heat from its surrounding
Endothermic
An animal that derives most of its body heat from its own metabolism
Monotremes
An egg-laying mammal such as duck billed platypus
Placenta
In the mammals, the organ that provides nutrients/oxygen to the embryo and helps dispose of its metabolic wastes; formed of the embryo’s chorion and the mother’s endometrial blood vessels
Marsupials
A pouched mammal, such as a kangaroo, opossum, or koala; give birth to embryonic offspring that completes development while housed in a pouch and attached to nipples on the mother’s abdomen
- australia, new zealand, central/south america
Marsupium
The external pouch on the abdomen of a female marsupial
Eutherians
Placental mammals; those whose young complete their embryonic development w/in the uterus, joined to the mother by the placenta
Placentals
Mammals whose young complete their embryonic development in the uterus, nourished via the mother’s blood vessels in the placenta
Protostome
An animal w/ a coelom that develops from solid masses of cells that arise b/w the digestive tube and the body wall of the embryo; includes mollusks, annelids, and arthropods
Deuterostome
An animal w/ a coelom that forms from hollow outgrowths of the digestive tube of the early embryo;includes echinoderms and chordates
