Animalia Flashcards
Common Characteristics of Animals
Multicellullarity Heterotrophs No cell walls: flexibility Nervous tissue: rapid response Muscle tissue: movement Sexual reproduction small, mobile sperm; larger egg Extracellular matrix: collagen Special clusters of Hox genes: patterns body axis Similar rRNA Characteristic cell junctions: anchoring, tight, gap
2 Major Categories:
Invertebrates
Vertebrates
Vertebrates
With a backbone
1% of all animals
1 phylum (Chordata)
Invertebrates
Without a backbone
97 - 99% of all animals
Approx. 35 phyla (discuss 12)
cellular LO
Aggregations of cells, groups with specialized functions
- Division of labor
Cell-tissue LO
- Groups of similar cells arranged in definite patterns or layers with a common function = Tissue
- Many scattered cells still present.
Tissue-organ LO
- Tissues arranged into organs
- Organ consists of multiple tissue types and has a very specialized function
Organ-system LO
- Groups of organs working together to perform a particular function
- Systems associated with basic body functions
- 11 body systems:
Animals evolution developmental pattern
germ layers (Group of cells that behave as unit during early embryonic development; Give rise totissue/organ/system - morphogenesis)
triploblastic layers
endoderm
mesoderm
ectoderm
diploblastic layers
endoderm
ectoderm
Coelom
fluid-filled space around the gut in which organs are suspended
Benefits: more space, more SA, storage, support (Hydrostatic Skeleton),
incr body size/complexity
Protostome
– 1st embryonic opening becomes the mouth (Annelids, Arthropods, Molluscs)
Deuterostome
2nd embryonic opening becomes the mouth (Echinoderms, Chordates)
stem cells
ability to develop into any cell type
- retain capacity to divide
(Adult stem cells = multi- or uni-
potent)
