Practicle #4 Flashcards
Animalia
Apomorphies: diplontic life cycles, have collagen, chemoheterotrophs, multicellular with division of labor
Diplontic life cycle
Spend majority of their life cycle as diploid.
Collagen
Connective tissue.
Chemoheterotrophs
Digest other living things internally.
Porifera
Sponges
- sessile and benthic
- made up of cells embedded in mesohyal
- only “animal” with totipotent cells (change form and function throughout their cell cycles)
Apomorphies: aquiferous system, spicules
Spicules
Rigid structural materials
- embedded in mesohyl
- provide support/structure
- made of calcium carbonate, spongin, or silica
Aquiferous system
System of pores and canals that bring water through sponge (food, gas exchange, waste removal)
- ostia: draws water in
- oscula: expells water
Eumetazoa
All animals except sponges
Apomorphies: true tissues, cellular basement membrane, ectoderm and endoderm in embryonic development, gastrovascular cavity, beginnings of nervous system
Cnidaria
Jellies, sea anenomies, etc.
Many are diplontic with alteration of medusa and polyp generations
- polyp: sessile with tubular bodies
- medusa: pelagic with bell-shaped body
Apomorphies: radial symmetry, stinging sructures used to catch food and protection
Hydrozoa
Type of cnidaria
Apomorphies: alteraiton of generations occurs but one may be lacking, usually more conspicuous polyp
Scyphozoa
True jellyfish
Apomorphies: polyp stage usually reduced/absent and medusa dominant
Anthozoa
Sea anemones, sea pens, corals
Apomorphies: lack medusa stage, large calcium carbonate structures, symbiotic with zooxanthellae, sensitive to environmental change (coral bleaching – expel zooxanthellae and starve)
Ctenophora
Comb jellies
Apomorphies: radial symmetry, complete guts with mouth/anus, determinate cleavage
Determinate cleavage
Fate of cells after early 4 celled stage determined/specialized.
Bilateria
Animal lineages beyond porifer, cnidaria, ctenophora
Apomorphies: bilateral symmetry, cephalization, cerebral ganglion, triploblastic, radial cleavage in early development
Bilateral symmetry
Symmetry along the dorsal/ventral and posterior/anterior axes.
Cephalization
Formation of head region
Triploblastic
3 embryonic germ layers:
1) outer ectoderm
2) inner endoderm
3) middle mesoderm
Protostomia
Type of Bilateria
Apomorphies: ventral nervous system, body types: acoelomate, pseudocoelomate, coelomate
Lophotrochozoa
Type of protostomia
Apomorphies: spiral cleavage, trochophore larvae
Platyhelminthes
Type of lophotrochozoa
Apomorphies: flattened body, incomplete gut, no specialized circulatory/respritory systems, longitudinal and circular muscules
Rotifera
Type of lophotochozoa
Apomorphies: complete gut with mouth/anus, fluid filled cavity that functions as hydrostatic organs
Ectoprocta
Type of lophotrochozoa
Apomorphies: region around mouth with ciliated tenctacles for catching food/gas exchange, form complex colonies, common fouling organisms
Mollusca
Apomorphies: radula, calcareous spicules, muscular foot, mantle
Radula
Toothed tongue in mouth used as food scraper
Mantle
Outer dorsal body wall, specialized epidermal cells that secrete the shell
Shells
Calcareous spicule laid down and covered by periostracum, huge diversity, correlated with behaviors/habits
Muscular foot
Often flattened, ciliated sole with gland that produces mucus trail, move via contractions along foot
Tentacles and arms = modified foot
Mantle cavity
Between mantle and foot, houses gills and receives waste and reproduce materials, circulates water
Visceral mass
Large differentiated central tissues with organs
Mollusk diversity
Chitons, gastropods, cephalopods, bivalves.
Chitons
Earliest mollusks.
Apomorphies: 7-8 overlapping shell plates, mantle fused to shell plates, adhere strongly to surfaces
Gastropods
Slugs, snails
Apomorphies: freshwater/terrestrial/marine, well developed head, coiled shell, torsion
Gastropods
Well-developed head, sensory structures with eyes/tentacles/statocysts
Torsion
Happens during gastropod growth, rotation of visceral organs and mantle
Opisthobranchia
Gills behind their heart, not monophyletic
Nudibranch
Lost their shells, eolid (eat cnidarians) or dorid (eat sponges), brilliant coloration as warning sign to predators
Cephalopods
Nautilus, octopus, squid, cuttlefish, etc.
Apomorphies: well developed head, coild shell, siphuncle, spetate shell, beak-like jaws, tentacles, siphon, extensive ganglia (brain), ink sac
Siphuncle
Tube that extends from visceral mass into shell chambers, secretes gas for buoyancy regulation.
Septate shell
Shell with compartments seperated by septa
Siphon
For propulsion, reproduction, spreads ink
Extensive ganglia
Forms brain, very smart
Bivalvia
Clams, oysters, mussles, scallops, etc.
Apomorphies: shell with 2 plates/valves, gilled for filter feeding, no radula
Annelids
Segmented worms
Apomorphies: segmentation, head with protomium and perisomium, setae bundles
Polychaetes
Paraphyletic, mostly marine, free-living and tube building, parapodia, elaborate head
Lumbricidae
Earthworms
Apomorphies: hermaphroditism (male/female repro. organs), clitellum reproduction, mostly terrestial
Hirudinea
Leeches and other worms
Apomorphies: fresh/salt water, posterior body sucks, subdivision of body segments, interal clitellium, hermaphroditism
