Invertebrates I: Porifera, Cnidaria, Ctenophora Study Set
What is the common name and dominant form of Class Cubozoa?
• "Box Jellyfish" • "Sea Wasp" • Medusa Dominant
What are characteristics of Phylum Ctenophora?
• "Comb jellies" • Gelatinous zooplankton • 8 rows of cilia (comb rows)
What is the dominant form and examples of Class Anthozoa?
• Exclusively polyps • Includes corals and anemones (Note: Mutualisms with clown fish)
What are the important distinctions of Class Scyphozoa?
• Medusa Dominant • "Jellies"
What are some common characteristics of phylum porifera?
• No gastrulation • No true tissues • Similarity to choanoflagellates • Spongocoel (cavity inside) • Choanocytes (feeding cells) • Spicules: Hard support structures (composed of glass or CaCO3) • Symmetry: Radial or asymetric
What are the common characteristics of phylum Cnidiaria?
• Radial symmetry • Range of forms - lifecycle often alternate between forms • Gastrulation during development • True tissues • Diploblastic • Acoelomate (No body cavity) • Gut only has 1 opening "closed gut" (GVC) • Carnivores: Nematocysts
What are the charactertistics of class calcerea?
1. Spicules composed of calcium carbonate 2. The spicules are straight or have 3-4 rays. 3. Asconoid, synconoid, and leuconoid forms all occur.
What are the characteristics of class hexactinellida?
1. These are glass sponges with six-rayed spicules of silica (rarely chitin).
What are the steps of early development in animals?
1. Zygote 2. 8-cell stage (Morula) 3. Bastula (Gastrulation) 4. Gastrula
When did animal colonize land?
450 million years ago
When did the Cambrian explosion occur?
540 million years ago
When did the first animals appear?
750 million years ago
What are the details in deuterostome development?
8-Cell Stage: Radial and indeterminate Coelom Formation: Budding of the mesoderm Fate of Blastospore: Anus
What are the details in protostome development.
8-Cell Stage: Spiral and determinate Coelom Formation: Splitting of the mesoderm Fate of Blastospore: Mouth
What protist did the first "animals" diverge from?
A choanoflagellate ancestor
What are tissues?
A group of cells with similar form/function.
What class of sponge contains 95% of living sponge species?
Demospongiae
Are animals diploid or haploid phase dominant?
Diploid phase dominant
What is an example of a conserved trait?
Early development in animals (specifically gastrulation)
What are the germ layers present during development?
Ectoderm, Endoderm, and Mesoderm.
What does it mean to be diploblastic?
Germ layers consisting of ectoderm and endoderm only.
What does it mean to be triploblastic?
Germ layers consisting of ectoderm, endoderm, and mesoderm.
How are conserved and nonconserved traits used by the taxonomist?
Groups with conserved traits are more likely to share a common ancestor.
What does the endoderm consist of?
Internal organs
Are animals multicellular or unicellular?
Multicellular (Due to the division of labor between cell groups)
What does the mesoderm consist of?
Musculo-skeletal system
What does acoelomate mean?
No body cavity
What is the common name for phylum porifera?
Sponges
What does the ectoderm consist of?
The skin and parts of the nervous system.
What is radial symmetry?
Top and bottom only (circle)
What is bilateral symmetry?
Top and bottom, front and back
What structure in sponges is similar to choanoflagellates?
Choanocytes (feeding structures) are similar to choanoflagellates.
What group of protists are closely related to animals?
Choanoflagellates
How are choanoflagellates similar to sponges?
Choanoflagellates closely resemble choanocytes (feeding cells) in sponges.
What are the classes of sponges?
Class Calcarea, Hexactinellida, and Demospongiae.
What class of phylum cnidaria are polyp dominant?
Class Hydrozoa
What material is unique to animals?
Collagen
What are the types of arrangements of the body cavity?
Acoelomate, Pseudocoelomate, and Coelomate.
What are the types of sponge body forms?
Asconoid, Syconoid, and Leuconoid.
What does pseudocoelomate mean?
Body cavity bordered by mesoderm and endoderm.
What does coelomate mean?
Body cavity bordered completely by mesoderm.
What is the nutritional mode of animals?
Chemoheterotroph
Do animals have a cell wall?
No, they lack a cell wall.
Are animals predominantly asexual or sexual?
Predominantly sexual Adult (2n), Sperm and Egg (n)
