Lecture 15

Question 1

Chordate clades were constructed by analysis of ..

Answer 1

• molecular evidence
• anatomical evidence
• fossil evidence

Question 2

Tunicates

Answer 2

thought to be first group of chordate. doesn’t have a brain

Question 3

Chirdates that contain a head are referred to as..

Answer 3

craniates

Question 4

Craniates

Answer 4

head consists of brain, located at anterior end of dorsal nerve cord. contains a skull and all sensory organs

Question 5

Chordates are defined..

Answer 5

by the presence of an extensive defined backbone. vertebral column composed of vertebrae. protects contents of nervous system

Question 6

Tetrapods

Answer 6

jawed vertebrates with two pairs of limbs (first vertebrae on land)

Question 7

Amniotes

Answer 7

tetrapods with a terrestrially adapted egg. last major adaption to land on life

Question 8

Hagfish and lampreys

Answer 8

primitive chordates. both are craniates and jawless.

Question 9

Hagfish have a ..

Answer 9

notochord. strong flexible rod running the length of the fish body

Question 10

Lamprey have a..

Answer 10

rudimentary vertebral column and notochord. classified as vertebrates because of VC

Question 11

Hagfish

Answer 11

approx. 40 species. scavenge dead vertebrates. along bottom of the ocean. almost blind but good sense of smell and touch.

Question 12

How hagfish attack prey

Answer 12

enter prey through existing holes. or create holes using charge structures on the tongue (like teeth) grasp and tear flesh. exudes slime from glands on the sides of its body when threatened. after threat is removed it ties its tail in a knot and slides forward to remove layer of slime

Question 13

Lampreys

Answer 13

oldest living vertebrates, suspension feeders. live in freshwater streams. most of the time spent buried in sediment. migration to the ocean or sea. occurs when the mature to adults. parasitic and attach to skin of prey with tongue and feeds on blood/tissue

Question 14

Jawed vertebrates

Answer 14

appeared on fossil record 470 million years ago. paired fins and tail. allows them to swim to prey. jaw enable them to catch and eat diverse group of prey. contact w suspension feeders.

Question 15

Jawed vertebrates with paired fins and gill are commonly referred to as//

Answer 15

fish

Question 16

3 linages of jawed vertebrates

Answer 16

• chondrichthyans
• ray finned fish
• lobe finned fish

Question 17

How evolution of jaw happened

Answer 17

initially skeletal rods supported the gill slits functioned to trap food particles. two pairs of skeletal rods near the mouth have become the jaws and their support. gill slits were no longer needed for feeding remained for gas exchange

Question 18

Chondrichthyans

Answer 18

sharks and rays. flexible skeleton made of cartilage. some sharks are suspension feeders. eat small floating plankton. most are predators that are quick and strong jaws and sharp vision. great sense of smell.

Question 19

Sharks have electrosensors which..

Answer 19

detect electromagnetic fields produced by muscle contractions of near animals

Question 20

Sharks have lateral line system which are..

Answer 20

row of sensory organs that run along each side of the animal. sensitive to changes in water pressure and detected very small vibrations caused by animals moving nearby

Question 21

Rays

Answer 21

adapted for life at the bottom the ocean. bodies are dorsoventrally flattened. eyes on top of the head. tail has sharp spines with venom glands art base. suspension feeders swim through the ocean filtering plankton

Question 22

Ray finned fish

Answer 22

tuna, trough and goldfish. skeleton made of bone and reinforced w cartilage. hard matrix of calcium carbonate. flattened scales over the skin and secrecy mucus to reduce drag while swimming. largest group of vertebrates (27000 species)

Question 23

Operculum on ray finned fish

Answer 23

protective flap on each side of the head. covers chamber housing the gills. movement of operculum allows the fish to breath w/o swimming.

Question 24

Contrast of operculum

Answer 24

sharks need to swim to pass water over their gills

Question 25

Swim bladder in ray finned fish

Answer 25

gas filled sac, a lung derivative. helps keep fish buoyant. evolved from balloon like lungs

Question 26

Lobe finned fish

Answer 26

rod shaped bones. found in muscular, pectoral and pelvic fins.

Question 27

3 linages of lobe finned fish

Answer 27

- coelacanth - lungfish - tetrapods

Question 28

Coalacanth

Answer 28

deep sea dwellers

Question 29

Lungfish

Answer 29

inhabit stagnant waters and gulp air into lungs connected to the pharynx

Question 30

Tetrapods

Answer 30

adapted to life on land and gave rise to terrestrial vertebrates

Question 31

Amphibians

Answer 31

salamanders and frogs. tetrapods, vertebrates with two pair limbs. most found in damp habitat. moist skin supplements lungs for gas exchange. skin usually have poison glands used in defence.

Question 32

Amphibians were the first to...

Answer 32

vertebrates to colonize land. distribution of most amphibians is limited because they require moisture because they are susceptible to dehydration. some amphibians live only on land (toads)

Question 33

Reptiles

Answer 33

lizards, snakes, turtles, and birds. dinosaurs. amniotes. major character that was derived here is amniotic egg

Question 34

Amniotic sac of reptiles

Answer 34

embryo develops inside enclosed by protective fluid sac called amnion. allows reptiles to complete their life cycle on land. similar to the role of the seed in plant evolution.

Question 35

Snakes become limbless because their ancestors ..

Answer 35

developed a burrowing lifestyle

Question 36

Reptilian skin

Answer 36

covered with scales, heavily keratinized to prevent drying out. not bale to breath through skin

Question 37

Reptiles breath using

Answer 37

a lung assisted with a ribcage

Question 38

Non bird reptiles referred to as cold blooded because..

Answer 38

don't use metabolism to generate body heat. stay in sun to stay warm. ectothermic

Question 39

Ectothermic

Answer 39

absorbing heat rather than producing

Question 40

Previous reptiles such as dinosaurs are though to be..

Answer 40

endotherms

Question 41

Reptilian group birds are descendants of..

Answer 41

one dinosaur linage

Question 42

Birds evolved from

Answer 42

theropods.

Question 43

Theropods

Answer 43

small 2 legged group of dinosaurs. suggested by fossils evidence. feathers present but not used for flight just insulation and courtship

Question 44

Archaeopteryx

Answer 44

most privative bird. feathered wings, teeth, wing claws, tail with vertebrae

Question 45

Most features of the bird reflect adaption that enhance flight like..

Answer 45

- reduce weight - no teeth - bones within the tail have only new hollow vertebrae - feathers w hallow shaft - bones w honeycomb structure for strength and light weight - large breast muscle provide power for flight

Question 46

Flying requires great deal of energy

Answer 46

- high metabolism rate - endothermic feather for no heat loss - very efficient circulatory system and lungs - strong sense/vision - amniotic eggs (hard shell)

Question 47

Mammals

Answer 47

amniotes with hair for insulation. endothermic. mammary glands produce milk for child. differentiation of teeth for consumption of varied food. larger brains. long period of parental care. high efficient circulatory/respiratory systems

Question 48

Mammals arose..

Answer 48

200 million years ago

Question 49

3 main groups of mammals

Answer 49

- monotermes - marsupials - eutherians

Question 50

Monotremes

Answer 50

duck billed platypus. only mammals that lay eggs. female lays 2 eggs and incubates eggs in nest. once born babies lick milk form mothers fur.

Question 51

Most mammals are born not hatched..

Answer 51

embryos are nourished inside mother. living of uterus together with embryonic layers form sac called placenta which allows exchange of nutrients and water to/from mothers body

Question 52

Marsupials

Answer 52

brief gestation. mother gives birth to tiny offspring that complete embryonic development attached to moms nipples. nourishing young usually contained in external pouch (marsupium) nearly all live in Australia, new Zealand, north and south america

Question 53

Eutherians

Answer 53

bear fully developed live young. called placental mammals. more complex than marsupials. entire embryonic development is completed within placenta