Invertibrate Exam Flashcards
Asymmetry
No body symmetry & grows as an irregular mass. Eg. Sponges
Radial Symmetry
Body parts are arranged around a central axis. Eg, Cnidarians
Bilateral Symmetry
A single plain divided body into left side & right side.
Types of Symmetry
Asymmetry
Radial
Bilateral
Classification System Levels
• Kingdom • Phylum • Class • Order • Family • Genus • Species Kinky People Can Often Find Good Sex
Kingdoms
• Monera bacteria • Protista amoeba, slime moulds, etc. • Fungi mushrooms, yeasts, etc. • Plantae • Animalia
Innovations in animal evolution
- Body Symmetry
- Tissues
- Body Cavities
- Embryonic development
- Segmentation
Acoelomate
No cavity - organs embedded in mesoderm,
Pseudocoelomate
False cavity - filled with fluid & suspended organs.
Coelomates
True cavity - better control since more muscles present .
Adult body parts are derived from which germ layers?
Endoderm
Mesoderm
Ectoderm
Embryonic development in triploblastic animals:
1 - Fertilisation 2 - Fertilised egg divides 3 - Blastula forms 4 - Gastrula forms (germ layers)
5 - Embryo develops
Deuterostome and Protosome stage differences
- 8 cell stage
- 32 cell stage
- blastopore
- mouth & anus development
Parazoa
General lack of any definite symmetry (sponges).
Eumetazoa
Have a symmetry.
Triploblastic
3 germ layers (EME)
Diploblastic
2 germ layers (EE)
Phylum Porifera –> Classes
Calcarea
Demospongiae
Hexactindellia
Mesophyl
A gelatinous, protein-rich matrix found between the choanocyte layer and the epithelial layer of the body of a sponge.
Spongin
Protien made by sponges as endoskeleton. 90% of sponges use spongin. (10% use collagen)
Hemaphrodite
Animal containing both female & male reproductive organs.
Gonochoristic
Animal containing male OR female reproductive organs.
Metamerism
Evolution of head & brain area in the anterior end of animals.
Nephridia
A tubule that open to the exterior of an invertebrate and acts as an organ of excretion or osmoregulation. Typically has ciliated or flagellated cells and absorptive walls.
Phylum Cnidaria –> Classes
Hydrozoa Scyphozoa (jellyfish) Cubazoa (box jellyfish) Anthozoa (corals and anemones) Staurozoa (star jellies)