Lecture 5: Animal Diversity Flashcards
heterotrophy
- animals ingest & digest food
- ancestorial trait bc its not unique to just animals
animal cell structure
- eukaryotic
- lack cell walls & are multicellular
extracellular matrix
- what cells use to communicate with one another
- derived characteristic of animals
- made of protiend that are external to plasma membrane
orginization of animals
- ## having muscle and nerve cells give animals ability to move
all animals have
specialized cells
most animals have
specialized tissues
higher forms of animals have
specialized organs
animal reproduction
- reproduce sexually with 2n stage dominating life cycle
- meosis & fertilzation occurs
what are the steps of embryonic development
- cleavage
- blastula
- gastrulation
- gastrula
- some animals develop into adults
- some will have 1 larval stage
- development is regulated by gene expression
cleavage
series of mitotic divisions without cell growth between divisions
cells will keep getting smaller without the growth
blastula
hollow ball of cells that surrounds the blastocoel
gastrulation
embryo folds inwards, expands, and fill the blastocoel
gastrula
- has endoderm (inner layer) and ectoderm (outer layer)
- has archenteron (pouch) which eventually becomes the digestive system (gut) of the embryo
metamorphosis
- process which larva goes from larva to a juvenile stage which resembles and adult
homeobox genes
- genes that code for proteins that regulate the expression of developmental genes
- homologous in all eumetazoans ( derived characteristic)
hox genes
important role in embryonic development
body plans
a particular set morphological and development characters, character represents key steps of evolution of animals
specialized tissues
- first major step in animal evolution
symmetry
- arrangement of body structures in relation to the axis of the body
radial symmetry
- multiple planes can be drawn to divide the animals into mirror images
- tend to be sissle ( dont move around)
bilateral symmetry
one plane through the midline
- associated with cephilization
asymmetry
- no line can produce mirror image ( porifera, sponges)
germ layers
concentric layers of embryonic tissue
ectoderm
outer coverings and the nervous system in some of the phyla
endoderm
lines archenteron that forms during gastrulation. endoderm develops into the lining of the digestive tube
mesoderm
gives rise to most other body structures such as muscles, skeleton and circulatory systems
coelom
fluid filled space between body wall and digestive tube
only triploblasts have a coelom
acoelomate
tribloblastic but lack a coelom, bodies are solid with no fluid cavity
pseudocoelomate
fluid filled coelom, body is formed from endoderm and mesoderm but it is not completly lined with mesoderm
eucleolomate
true coelom, body cavity is completly lines with mesoderm
animal development
- cleavage
- cooelom formation
- fate of the blastospore
protostomes
- first mouth
- cleavage is spiral, and determinate
- solid masses of mesoderm split and form coelom
- develops into the mouth
deuterostomes
- second mouth
- cleavage is radical, planes are parrel or perpindicuale
- indeterminate
- folds of mesoderm from archenteron form coelom
- becomes anus
