Comp. Anatomy Ch. 10

what does the appendicular skeleton consist of? 3

pectoral
pelvic girdles
skeleton of the fins/limbs

what are modifications of a basic morphologic pattern seen in early bony fishes
what does it consist of? 2

-all osteichthyan pectoral girdles
Consists of:
-3 cartilages or endochondral bones
-4 or 5 membrane bones derived from dermal armor

coracoids, scapulae, and suprascapulae are...

endoskeletal

what are separate adult features and are absent in therian mammals?

coracoids

what is universal except for in species that lack forelimbs?

scapulae

clavicles, cleithra, supracleithra, posttemporals and postcleithra are..

dermal bones

clavicles occur in all classes of bony vertebrates but are best developed in..

terapods

what is a tetrapod character retained in living reptiles and monotremes?

a midventral interclavicle of intramembranous origin

recent bony fishes have tended to lose the replacement bones of the..
tetrapods have tended to lose

pectoral girdle
-dermal bones

what kind of bones ARENT in the pelvic girdle

dermal bones

the pelvic girdle of fishes consists of _ ___ ____that articulate laterally w/ a pelvic fin and usually meet ventrally in a symphysis.
the plates unite to form a ____ ___ in sharks and lungfishes

2 pelvic plates
-median bar

in tetrapods, 2 ossification centers in each pelvic plate become..2

ischial and pubic bones

what braces the girdle against the vertebral column...1

an ilium

ilium, ischium, and pubis unite to form an..
and what does in enclose?

innominate bone (os coxa) in mammals
-an obturator foramen

what is associated with the pelvic girdle midventrally that are in some urodeles
and in reptiles, monotremes, and marsupials?

prepubic (ypsiloid) cartilages
-epipubic & hypoischial cartilages

what does the sacrum and pelvic girdle of mammals and some reptiles constitute of?

a pelvic that encompasses a pelvic cavity

what are the 3 types of paired fins

lobed (sarcopterygii)
fin fold fins (chondrichthyes)
ray fins (actinopterygii)

what consists of layered rows of basal and radial cartilages or bones?

skeleton of a generalized fin (paired or median)

what do lobed fins have?

-a central bony axis
-pre/postaxial radials

ray fins have lost...

basals & radials

what do cartilaginous fishes have?

fibrous fin rays --> ceratotrichia

what do the rays of bony fishes (lepidotrichia) consist of?

jointed dermal bones

dorsal and anal fins are..

unpaired

caudal fins are homocercal, heterocercal, hypo...depending on what?

depending on the direction taken by the notochord and vertebral column in the fin

Residual components of neural and hemal arches and spines of modified caudal vertebrae makes up what?

the basal skeleton of homocercal fins

origin of fins

unknown

tetrapod limbs are modifications of...

rhipidistian fins

limb skeletons consist of (PEA)

propodium --> humerus/femur
epipodium --> radius/ulna/tibia/fibula
autopodium --> manus/pes

modifications of the manus and pes involve

-reduction in the # of bones
-disproportionate lengthening or shortening of segments
-and in some aquatic tetrapods, increase in # of phalanges

what has been reduced to 4 or fewer in modern amphibians?

digits
-3 in birds
and as few as 1 in some ungulates

loss of digits is accompanied by

loss or reduction of associated carpals/metacarpals or tarsals/metatarsals

the most striking modifications of the manus are in...3

flying tetrapods
water adopted amniotes
and in ungulates

what are plantigrade digitigrade or unguligrade

mammalian stances

ungulate foot are (3)

hoofed
mesaxonic
or paraxonic

why have a reduced number of ankle bones in birds have fused with the tibia and metatarsals

to add an additional elongated segment to the hind limbs

what does an intratarsal joint adds?

adds flexibility of the pes

excepting sesamoid bones, bones of fins, and limbs are all...

endochondral

how do most fishes swim?

lateral undulation

anterior flippers, lateral undulation, sculling in marine tetrapods allow them to do what

forward thrust
or in cetaceans, galloping

of the limbless terrestrial tetrapods, what organism show the largest number of adaptations for locomotion?

Snakes!

modifications of what are among the adaptations that enable true flight?

-manus