lecture 5a

Question 1

Name the large bones that make up the upper fore limbs?

Answer 1

scapula, humerus, radius/ulna

Question 2

Give the name of the bones that make up the manus

Answer 2

carpals, metacarpals and phalanges

Question 3

Name the bones that make up the ind limbs

Answer 3

femur (attaches to pelvis) fibula/tibia

Question 4

name the bones that make up the pes (or foot)

Answer 4

tarsals, metatarsals and phalanges

Question 5

Pelvic girdle: describe the three functions of this structure

Answer 5

1) when walking or standing, serves to transfer weight from limbs to the rest of skeleton and vice versa 2) protect some lower organs 3) serves as attachment of muscles

Question 6

Pelvic girdle: paired set bones each consists of which three parts?

Answer 6

ilium, ischium, pubis

Question 7

Does the pelvis attach to the vertebral column? if so which bones are involved? Difference with, if so what is it?

Answer 7

the ilium and sacral vertebrae may attach. Loose in young and fully fuse in adults

Question 8

What is acetabulum?

Answer 8

the attachment point (socket) for the femur. It is located on the pelvic girdle

Question 9

fore limbs: Pinniped What are appendages described as?

Answer 9

flippers

Question 10

Fore limb: pinniped describe the Otariidae’s pectoral flipper? How do they move?

Answer 10

When on land, they use their hind limbs to assist them. they have thick bones of upper arm and thin scapula

Question 11

hind limb: pinniped describe the phocids pelvic flipper? How do they move?

Answer 11

The drag their hindlimb behind when walking on land. they have shorter strong femur, tibia and fibula. Fibula is fused at the top end with the tibia. Also they have long pes

Question 12

fore limbs: pinnipeds 1. What are they called? 2. what bones make up this structure? 3. What bones make up the hand? 4. What is another name for the hand?

Answer 12

1. pectoral flippers 2. scapula, radius, ulna 3. carpals, metacarpals, and phalanges. 4. manus

Question 13

hind limbs: pinnipeds 1. What are they called? 2. what bones make up this structure? 3. What bones make up the foot? 4. What is another name for the foot?

Answer 13

1. pelvic flippers 2. femur, fibula and tibia 3. tarsals, metatarsals and phalanges 4. pes

Question 14

Appendicular: Cetaceans –> forelimbs 1. What are the these called? 2. what bones make up this structure? 3. what bones make up the hand 4. what is another name for the hand?

Answer 14

1. pectoral fins 2. scapula, humerus, radius/ulna 3. carpals, and metacarpals 4. manus

Question 15

Appendicular: Cetaceans –> hind limbs (caudal fin) Do cetaceans have hind limb appendages? (describe their pelvis been and relationship to spinal column)

Answer 15

lost all bones in their hind limbs “reduced vestigial pelvic bones” is what remains that aren to attached to the vertebral column.

Question 16

Appendicular: Cetaceans –> caudal fins What is the tail or fluke composed of?

Answer 16

• very thin layer of blubber - a layer of tough ligaments - core of tough and dense fibrous tissue - supported by very small vertebrae that extend almost to the fluke notch but not into fluke

Question 17

Appendicular: Cetaceans –> caudal fins What is the reason for the composition in the tail or fluke

Answer 17

penetrating the fibrous core is a system of BV that are arranged as heat retaining counter current system

Question 18

Appendicular: Sirenians –> fore limbs 1. What are the these called? 2. what bones make up this structure? 3. what bones make up the hand 4. what is another name for the hand?

Answer 18

1. pectoral flippers 2. scapula, radius/ulna NO humerus 3. carpals, metacarpals, and phalanges 4. manus

Question 19

Appendicular: Sirenians –> hind limbs do they have pelvic appendages? what do they do hav instead?

Answer 19

NO, and no dorsal fin. They do have reduced vestigial pelvic bones remaining that are NOT attached to the vertebrae column

Question 20

Appendicular: Sirenians –> caudal fins 1. what is consists of 2. difference between the two subspecies?

Answer 20

1. broad rounded fluke 2. dugongs have two flukes

Question 21

Appendicular: Sea otters –> fore limb 1. Describe the sir of the scapula compared to river otter. 2. are there any differences in the rest of the forelimb?

Answer 21

1. scapula is smaller than the river otters 2. rest of the fore limb is composed of similar bones as other marine mammals

Question 22

Appendicular: Sea otters –> hind limbs 1. describe the unique characteristics of their hind limbs and what this allows for. 2. are there any differences in the rest of the hind limb?

Answer 22

1. web of skin between digits –> surface area of the foot doubles when spread –> increase propulsion though the water 2. rest of the hind limb is composed of similar bones as other marine mammals

Question 23

Appendicular: Polar bears 1. What if anything is unique about their necks? 2. what does this allow them to do?

Answer 23

1. long necks 2. strong muscles that attach onto the neck that are well developed and used for attacking and handling out heavy prey out of the water

Question 24

Appendicular: Polar bears are their skeletal features different form other terrestrial mammal?

Answer 24

no, they have similar skeletal features to other marine/terrestrial mammals (couple hind and fore limb bones) ++ short tail

Question 25

Appendicular: Polar bears 1. Describe their swimming style 2. what adaptations (if any) have to help

Answer 25

1. crawling motion while hind limbs drag behind 2. large strong fore limbs; feet that form flat like plates (easier walking on snow and on land)

Question 26

What general skeletal changes have cetaceans and sirenians made to adapt to totally living in water and what 2 main skills has that allowed for.

Answer 26

skeletons of cetaceans and sirenians have become adapted totally living i water by losing their HIND limbs and making anatomically changes to compensate for buoyancy control and propulsion

Question 27

Pinnipeds, sea otters and polar bears have made changes in their skeletons that reflect what 2 main issues?

Answer 27

skeletons reflect their various modes of propulsion through water and the fact they they live at least part of their lives on land.