Biology Exam 2 Flashcards
Define polyphyletic
could have multiple different answers, ex. aschelminthes
define pseudocoelome
false body cavity, lacks peritoneal linings and membranes, often fluid-filled
define hydrostatic skeleton
fluid, mostly water, exerts pressure, which gives support and shape
What are some characteristics of Aschelminthes?
phylum of pseudocoelmates with hydrostatic skeletons, cuticle, pharynx, complete digestion, mostly dioecious, microscopic, protoniphridia, no circulatory system, primitive brain, no real eyes, and eutely
What is a cuticle?
a thin, protective layer that covers the body
dioecious definition
separate sexes
define eutely
number of cells constant for each organ and the entire animal in all individuals of a given species
Summarize Rotifera
2000 species, Phylum Rotifera, freshwater, corona for feeding, master to grind food, foot with 2 toes, parthenogenetic
define parthogenesis
all female reproduction
Summarize Spiny-headed worms
Phylum Acanthocephala, 1000 species, endoparasites, retractable proboscis, no digestive system, arthropod host then fish
Name the 5 ecdysozoans
Nematoda, Nematomorpha, Anthropoda, Onychophora, Tardigrada
Summarize Roundworms
Phylum Nematoda, 1600 species, parasitic or free-living, cuticle is molted 4 times, chemoreceptors, complete digestive, osmoregulate, dioecious
define osmoregulation for nematodes
free-living nematodes have ventral glands, renettes, that absorb wastes from pseudocoelom, whereas parasitic ones have a tubular system with long canals and an excretory pore.
Giant Intestinal Roundworm
Nematodes, single host, lives in small intestine
Pinworm
Nematoda, single host, large intestine, eggs hatch and molt in small intestine
Horsehair Worms
Nematomorpha, 250 species, very long, skinny worm, in running or standing water, free-living adults, larvae parasitize arthropods
Summarize Phylum Mollusca
100,000 species, protostomes, lophotrochozoans, coelom,, 3-part body, head-foot, visceral mass, and mantle, noticeable head, radula, digestive system, open circulatory system, mantle cavity, dioecious
What are the functions of the coelem
room for organ development, diffusion surface for gases, nutrients, and wastes, storage, elimination of reproductive product, hydrostatic support
What is contained in the visceral mass of mollusks?
digestive, circulatory, reproductive, and excretory organs
Mantle cavity functions
excretion, gas exchange, elimination of wastes, release of reproductive product
define radula`
tongue-like rasping structure
Summarize Snails and Slugs`
Phylum Mollusca, Class Gastropoda, gastro meaning stomach soda meaning foot, 350,000 species, largest class, some venomous, torsion, breathe through single gill in mantle cavity, hydraulic skeleton, open circulatory system, mucous gland, real eyes, dioecious
Define torsion
180 degree twist of visceral mass, mantle, and mantle cavity that positions gills, anus, reproduction, and excretory openings behind the head
Summarize Clams, ysters, Mussels, Scallops
Phylum Mollusca, Class Bivalvia, bi meaning 2, valve meaning valves, 2nd largest class, 300,000 species, laterally compressed, no head or radula, wedge-shaped foot, gills, filter feeding, open circulatory, dioecious, marine and freshwater
Summarize Octopi, Squid, and Nautilus
Phylum Mollusca, Class Cephalopoda, may have shell, 550 species, marine, largest invertebrates, complex eyes, anterior foot, mantle cavity with jet propulsion, release ink, beak-like jaws and a radula, some venomous, closed circulation, complex nervous system, dioecious, special tentacle for reproduction
List classes under Annelida
Polychaeta, Clitellata, Hirudinea
Define Metamerism
diversion of body into serially repeated sections along anterior/posterior axis
Describe the digestive system of annelida
complete digestive system forming straight tube through the body
Define tagmatization
modification of body regions for specialized functions
Summarize Class Polychaeta
Tubeworms, Clamworms, and Fanworms, 5300 species, marine, live in shells, rocks, or burrows, move with setae and parapodia, undulating, or swimming, greater cephalization, have prostomium, eyes can be simple receptors or complex eyes, range from predators to herbivores, typically dioecious with external fertilization
Summarize Class Clitellata
Earthworms and Leeches, monoecious, few or no setae, 3000 species, burrowing, no parapodia, low cephalization, move with antagonistic contraction or circular and longitudinal muscles, small protstomium, monoecious
Define protstomium
lobe dorsal and anterior to the mouth that contains numerous sensory organs, including antennae, and eyes, like a head
Summarize Subclass Hirudinea
Leeches, most freshwater, 500 species, no parapodia or setae, low cephalization, suckers anterior and posterior, coeliac sinuses, anticoagulant and anesthetic in saliva, don’t molt
