CH 32 Flashcards
Animals
multi cellular, heterotrophic eukaryotes with tissues that develop from membrane layers
Nutrition
Animals differ from plants and fungi in terms of their _____
True
Plants are autotrophic eukaryotes capable of photosynthesis
enzymes
Animals ingest living/non-living matter then use ____ to digest
True
animals have no cell walls
collagen
most abundant protein - NOT found in plants or fungi
Tissues
groups of smaller cells that act as one functional unit
muscle and nerve cells
central to the animal lifestyle
sexually; diploid
most animals reproduce ______ and the _____ stage usually dominates the life cycle
Haploid stage
sperm and egg cells are produced directly by meiotic division forming a diploid zygote
cleavage
zygote undergoes _____ - a succession of mitotic cell divisions without growth between the divisions
blastula
formation of a multi cellular stage - in many animals it takes the form of a hollow ball
adults; larval
Some animals develop directly into _____, but in life cycles of most animals there is a ____ stage
larva
sexually immature form of an animal that is morphologically distinct form the adult - usually eats different food and requires a different environment
metamorphosis
the developmental transformation that turns an animal into a juvenile that resembles the adult but is NOT yet sexually mature
Homeoboxes
sets of DNA sequences
hox genes
regulate the formation of anterior and posterior axis, as well as other aspects of develoment
True
sponges don’t have hox genes - they have other homeoboxes that influence their shape
Choanoflagellets
closest living relatives of animals
Neoproterozoic Era
1 billion - 542 million years ago - fossils found in this era - first sightings of Ediacaran biota
Endiacaran Biota
Soft-bodied, multi cellular eukaryotes - some thought to be molluscs, while others closely resemble porifera and cnidarians
