What are the defining features of eukaryotes?
- Cytoskeleton
Where did animals come from?
A single-celled ancestor called a choanoflagellate.
What are characteristics of the family Choanoflagellata?
- Heterotrophic •Single flagellum with collar •Suspension feeders •Solitary or colonial •Sister taxon of Metazoa •Choan = funnel (Greek)
Describe Dinoflagellata.
Describe Ciliophora.
How do Paramecium reproduce?
What are some advantages of multicellularity?
What is the difference between Protozoans and Metazoans?
“Protozoans are eukaryotic, largely unicellular organisms that do not undergo tissue formation through the process of embryological layering.”
“Metazoans are heterotrophic multicellular eukaryotes that undergo embryogenesis by way of tissue layering.”
What are the theories of Metazoan Origin?
Colonial Theory: Metazoa as derived from a colony of flagellated Protozoa, Cell division without separation (currently believed to be correct).
Syncytial Theory: Metazoa as derived from a multi-nucleate but unicellular like a ciliate protozoan, large multinucleate cells that eventually partitioned into compartments, and not much support.
What are apomorphies of Porifera?
Apomorphies
•Microvillar collars surround flagella(choanocytes) arising from single cells or syncytia
•Homologous with choanoflagellates??•Adults sessile and filter feeders, larval stages motile
•Collagen
•Skeletal elements(calcium carbonate and silicondioxide and collagen)
•Aquiferous system
What are apomorphies of Demospongiae
Apomorphies •Spongin-based skeleton (a type of collagen) •Siliceous tetraxons •Spongocytes •Most (>80%) sponges
What are the three general forms of Porifera (sponges)?
Asconoid (thin)
Syconoid (medium)
Leuconoid (large) - all large sponges are leuconoid.
What are apomorphies of Calcarea (Porifera)?
Apomorphies •Calcium carbonate (calcite) spicules •Won’t dissolve in HCL •Large choanocytes •Coeloblastula larva (hollow)
What are apomorphies of Homoscleramorpha (Porifera)?
Apomorphies
•Never with a spongin skeleton;
•Only sponge with basal lamina
•Shallow waters
What are apomorphies of Hexactinellida (glass sponges)
Apomorphies
Describe Placozoa.
What are apomorphies of Cnidaria?
Apomorphies •Stinging cells (cnidocytes) •Polyp adult and planula larva •Nerve nets •Longitudinal and circular muscle •Endodermal gonads •Circular mitochondrial DNA (anthozoans) & linear mtDNA
What is a Cnidae: Nematocyst?
What are the cell types of Cnidaria?
Cell Types •Cnidocytes •Muscle •Nerve •Glandular •Interstitial •Ciliated •Sensory •Germ
What are apomorphies of Anthozoa (Cnidaria) ?
What are apomorphies of Scyphozoa?
Medusa with:
•Rhopalia(sense organs), which has
- Mesogleal, gastrodermal and epidermal components
- Gastrodermalstatocyst, mechano, photo, and chemoreceptor
•Gastric filaments
•Strobilation
What are apomorphies of Cubozoa?
What are apomorphies of Hydrozoa?
Apomorphies: •Medusa with velum •Endodermal cnidocytesabsent •Gastrozooids: feeding •Gonosooids: reproductive •Dactylozooids: defense and prey capture
What are apomorphies of Ctenophora?
Biradial symmetry •Diploblastic?? (tri) •Aboral organ •Ciliary rosettes •Photocytes •Ctene rows •Collocytes