Chapter 9- appendicular skeleton

Question 1

paired fins/limbs and girdles attaching appendages to axial skeleton

Answer 1

appendicular skeleton

Question 2

two girdles

Answer 2

pectoral and pelvic

Question 3

membranous or webbed processes reinforced by internal fin rays

Answer 3

fins

Question 4

elasmobranch rays are made of

Answer 4

ceratotrichia which are keratinized rods

Question 5

bony fish rays are made of

Answer 5

lepidotrichia which are ossified/cartilage rays

Question 6

proximal, mid, and distal fin support

Answer 6

basal pterygiophores
radial pterygiophores
rays

Question 7

what are the two sets of paired fins

Answer 7

pectoral and pelvic fins

Question 8

a limb - muscular appendage with well defined joints and distal digits

Answer 8

chiridium

Question 9

morphological term for upper arm or thigh

Answer 9

stylopodium

Question 10

morphological term for forearm or shank

Answer 10

zeugopodium

Question 11

morphological term for manus or pes

Answer 11

autopodium

Question 12

pectoral articulation

Answer 12

glenoid fossa

Question 13

pelvic articulation

Answer 13

acetabulum

Question 14

two big roles for the fins

Answer 14

stabilization in the water

role in locomotion

Question 15

three motions of fins

Answer 15

roll, pitch, yaw

Question 16

two theories of fin origin

Answer 16

gill arch theory

fin-fold theory

Question 17

fins and girdles derived from gill arches

Answer 17

gill arch theory

Question 18

whats so hard to explain about the gill arch theory

Answer 18

it doesn’t account for the pectoral fins

Question 19

pelvic and pectoral fin sets derived from two continuous ventrolateral folds of ancestral fish

Answer 19

fin-fold theory

Question 20

what is interesting about limb development

Answer 20

asymmetric development

Question 21

early tetrapods only have made of three parts called

Answer 21

one bone in the pelvic girdle

illium, ischium, pubis

Question 22

bones of the digits

Answer 22

metacarpals/metatarsals and phalanges

Question 23

bones of wrist/ankle

Answer 23

carpals/tarsals

Question 24

primitive tetrapods have this many digits and this many digits became established as the common plan

Answer 24

more than 5

5

Question 25

four reasons to move from aquatic to terrestrial life

Answer 25

fishes able to move to move from water to water over land
avoid predation by moving to shallows or onto beaches
breath air where there is more oxygen
there is abundant food sources on land

Question 26

what is the difference between early tetrapod/ amphibian/reptile movement and eutherian mammal movement

Answer 26

lateral limbs vs limbs drawn under the body

pendulous limb vs overarm swing

Question 27

what is the advantage of having limbs under the body

Answer 27

allows for better locomotion with the limbs only moving in one plane

Question 28

what is another word for running

Answer 28

cursorial

Question 29

what was the structural change in the limb design when limbs are drawn under the body

Answer 29

forelimbs are now under the scapula and have a greater role in weight bearing
there is a reduction of pectoral girdle elements

Question 30

in mammals how does the flexion of the vertebral column change

Answer 30

shift from lateral flexion to vertical flexion

Question 31

three hypotheses on the evolution of bird flight

Answer 31

bipedal tree dwelling ancestor
feathered limbs as insect catchers
feathered limbs to support running