L4 Characteristics and Evolution of Animal Bodies Flashcards
Heterotrophic
Organisms that obtain energy from consuming others.
Multicellular
Organisms composed of multiple cells.
Eukaryotes
Organisms with complex cells containing a nucleus.
Metazoans
Multicellular animals forming a single clade.
Ediacaran Period
570-539 million years ago; early multicellular life.
Cambrian Explosion
Rapid diversification of animal life around 540 million years ago.
Trilobite
Extinct marine arthropod from the Lower Devonian.
Priapulids
Small phylum known for ancient burrows.
Segmental Specialization
Variation in function among body segments.
Metamerism
Body structure formed of repeated segments.
Tagmosis
Fusion of body segments into functional units.
Coelom
Internal cavity in most bilaterian animals.
Protostomes
Blastopore develops into the mouth during embryogenesis.
Deuterostomes
Blastopore develops into the anus during embryogenesis.
Embryogenesis
Development process from fertilization to gastrulation.
Symmetry Types
Asymmetric, radially symmetric, bilaterally symmetric.
Model Organisms
Species commonly used for biological research.
Caenorhabditis elegans
Model organism with a known cell lineage.
Homeotic Genes
Genes that determine segment identity in organisms.
Hox Genes
Genes controlling body plan development in animals.
Drosophila
Model organism for studying genetics and development.
Collinearity
Order of genes along chromosomes matches expression domains.
Eye Development Genes
Genes inducing eye formation in Drosophila and mice.
Nematoda
Phylum including roundworms, with over 1 billion cases.
Arthropoda
Phylum including insects, crustaceans, and arachnids.
Chordata
Phylum including vertebrates and related organisms.
Gastrulation
Early embryonic stage where cell layers form.
Ediacaran Animals
Early multicellular life forms, not assigned to living phyla.
Fuxianhuia
Cambrian arthropod with complex brain structure.
Segmental Identity
Specific characteristics assigned to body segments.
