Week 2 Vocabulary Flashcards
Chrodata
a phylum, named for the notochord
Uro | chodate
“tail” chordate
few cm that filter feed with a basket-like perforated pharynx, most adults are sessile
Cephalo | chordate
“head” chordate
25 species of lanclets
small, superfically fish-like marine animals, less than 5 cm
Metazoans
multicellular heterotrophs, motile during their life cycle
BIlateria
a phylam of animals that at some point in their life cycles have a body plan with two sides that are mirror imagery
Pro | to | stomia
“earlier” “mouth”;
develops that mouth before the anus during gastrulation
defines all metazoans
Deutero | stomia
“second” “mouth”
Blasto | pore
the orignial embryonic gut opening
becomes the mouth of protostomed
or th anus of deutrostomes
“small opening”
Echinoderm
part of the phylum echinodermata; lack a distinct head and have five fold symmetry
Inversion hypothesis
the hypothesis that the dorsal and ventral sides of chordates were inverted at some point during their evolutionaty history
myomeres
blocks of striated muscle fibers arranged along both sides of the body and separated by connective tissue sheets
cerebral vessicle
brain of the lanclets, thickening at the front of the spinal cord
olfactores
a grouping that includes vertebrates and cephalocordates, as they are sister taxon
centrum
the main weigh supporting body of a vertebra that cushioned by the spinal disc
forms around the nerve cord and the notochord during development
gnathostomes
vertebrates with jaws
coelom
the formation of the body cavity in vertebrates from the solid mesoderm
mesenteries
sheets of peritoneum usesd to suspend the gut in the peritoneal cavity
Hox genes
regulate expression of the heirarchial network of developmental genes
occur in clustes that are arranged in the same linear sequences as the structures they control
MicroRNA
are noncoding RNA sequences about 22 bases long that have been added to metazoan genome
regulate the synthesis of proteins by binding to complementary base sequences of messenger RNAs
Neural crest
“fourth germ layer”
migratory ability and their ability to differentiare into many different types of cells in the body
Placode
thickenings of the embryonic epiderm that give rise to various sensory and cutaneos structures
Epithelial tissues
sheets of tightly connected cells and form the boundaries between the inside and the outside of the body and between compartments within the body
Muscle tissues
made of actin and myosin
they work together to cause muscle cells to contract and exert force
Neural tissues
neurons and glial cells that transmit information and insulation between neurons and surroundings
Connective tissues
provide structural support, protection, and strength
Dermal bone
formed in the skin and lacks a cartilagenous precursor
Endochondral bone
made of osteocyed that form from a caartilagnous precousr within the body; unique to body fish and tetrapods
Perichondral bone
formed deep in the body but forms in perichondral membrane around cartilage or bone
Dermato | cranuim
“skin” “skull”
forms in the skin as an outer cover ;
anterior- neural crest
posterior- regular mesoderm
Blood
fluid connective tissue made of plasma, erythrocytes, hemoglobin, and leukocytes
Vestibular apparatus
originally structures in the inner ear
detect an animal’s position in space and these structures retain that function today in both water and land vertbrates
