Morphology General Zoology, 24 January 2011 Donald Winslow Readings from Hickman et al. 2011: Ch. 9 pp 185-189, 191-193, 195-196
Morphology Biological hierarchy Grades of organization & body plans Describing locations on animal bodies Body cavities & germ layers Developmental patterns Histology Body size
Biological hierarchy Cell Tissue Organ Organ system Organism Population Community Nine-banded armadillo
Grades of organization Protoplasmic (e.g. protozoa) Cellular (e.g. colonial protists, sponges) Tissue or “cell-tissue” (e.g. jellyfish) Organ or “tissue-organ” (e.g. flatworm) Organ system (e.g. molluscs, arthropods) Luna moth
Body plans Unicellular protists vs multicellular animals Protozoa vs Metazoa Cell-level vs tissue-level organization Porifera vs Eumetazoa Radial symmetry vs bilateral symmetry Sac vs “tube-within-a-tube” digestive tracts Acoelomate, pseudocoelomate, coelomate
Patterns of symmetry Bilateral symmetry Radial symmetry Photo by Richard Snow
Describing location on animal Anterior/posterior Dorsal/ventral Medial/lateral Distal/proximal Frontal, sagittal, and transverse planes
Body cavities Blastocoel Gastrocoel (archenteron) Pseudocoel Coelom
Germ layers Endoderm Mesoderm Ectoderm
Developmental patterns Cleavage—radial or spiral Gastrulation (germ layer formation) Diploblastic or triploblastic Protostome or deuterostome Metamerism (segmentation)
Histology Blood plasma and interstitial fluids Tissues Endoderm epithelium of digestive tract Ectoderm skin & nervous tissue Mesodermconnective tissue, muscles, viscera Connective tissue: collagen, blood, lymph, cartilage, bone, fat
Advantages & disadvantages of large body size Predators can subdue larger prey, But larger prey can’t hide as easily. Larger animals have efficient metabolism, But use more energy. Larger animals have longer generations.
Humpback whale