Lab 8: vertebrates

Question 1

phylum and subphylum of all vertebrates

Answer 1

phylum chordata
subphylum vertebrata

Question 2

features of all chordates (6)

Answer 2

vertebrae
paired appendages
jaws
lungs
amniotic eggs
hair

Question 3

additional chordate features (8)

Answer 3

scales
fins
wings
feathers
2/3/4 chambered hearts
development of cerebral cortex
endothermy
placenta

Question 4

what are cyclostomes

Answer 4

jawless vertebrae
ex. myxini (hagfish) and petromyzontida (lampreys)

Question 5

two invertebrate subphylums

Answer 5

cephalochordata and urochordata

Question 6

hagfish and lampreys habitat

Answer 6

H: marine
L: freshwater

Question 7

similarities and differences between hagfish and lampreys

Answer 7

H: protective slime, slit mouth
L: parasitic, sucking mouth with teeth
Both: jawless

Question 8

lampreys and hagfish habit

Answer 8

H: scavenger
L: predator/parasitic

Question 9

hagfish and lamprey niche

Answer 9

H:scavenger
L: free-living

Question 10

how do hagfish and lampreys obtain their food

Answer 10

H: scavenge bottom of marine floor
L: suck blood/other fluid from host

Question 11

are myxini or petromyzontida more derived

Answer 11

petromyzontida : notochord is contained in sheath of cartilage

Question 12

gnathosome meaning

Answer 12

jaw mouth

Question 13

how were jaws developed

Answer 13

development of skeletal rods that used to support pharyngeal slits

Question 14

advantage of having a jaw

Answer 14

grip a wider variety of food and chew

Question 15

advantage of paired fins

Answer 15

increased stability and mobility = more efficient swimming/hunting

Question 16

what is a fish

Answer 16

limbless, cold-blooded vertebrate with gills, fins, live completely in water

Question 17

chondrichthyes meaning and examples

Answer 17

“cartilage fish”
ex. sharks, rays, chimaeras

Question 18

characteristics of chondrichthyes

Answer 18

jaw, skeleton made of cartilage, minerlaized teeth, gills, pectoral fins, ectothermal

Question 19

adaptations that make chondrichthyes good predators

Answer 19

jaws with sharp teeth, tail and fins for propulsion, gills for constant gas exchange, streamlined bodies

Question 20

are chondrichthyes the most acestral group of gnathostomes

Answer 20

no: placoderms

Question 21

osteichthyes meaning and examples

Answer 21

“bony fish”
ray-finned fish (actinopterygii) and lobe-fins (sarcopterygii)

Question 22

why are actinopterygii and sarcopterygii included in osteichthyans

Answer 22

posess swim bladder for buoancy

Question 23

what features do osteichthyans and chondrichthyans share

Answer 23

jaws, scales, gills, paired fins, ectothermal, direct development, oviparous (eggs that hatch after being laid)

Question 24

how do chondricthyans and osteichthyes differ

Answer 24

C: 5-7 gills, ventral mouth, marine, made of tiny placoid denticles covered in sharp enamel
O: 4 gills, terminal mouth, cycloids scales, marine/freshwater

Question 25

how have the body form and colour helped ray-finned fish survive

Answer 25

colour: indicates toxicity for protection body: better predication + protection

Question 26

two subgroups of sarcopterygii and what features do they share

Answer 26

actinistia (coelacanths) and dipnoi (lung fish) lobed fins, paired fins that articulate with pectoral and pelvic girdles with a single bone

Question 27

why are tetrapods thought to be related to lobe-fins

Answer 27

lungs are thought to have developed from swim bladder paired lobe fins - paired limbs covered in muscle and skin

Question 28

what is a tetrapod

Answer 28

vertebrates with four limbs with digits

Question 29

challenges tetrapods faced on land (3)

Answer 29

1: dessication 2: reproduction 3: soft eggs

Question 30

how did tetrapods adapt to live on land (3)

Answer 30

1: kentin in skin for water solubility 2: amniotic sac to keep eggs moist 3: hard-shelled eggs

Question 31

examples of amphibia

Answer 31

salamanders, frogs, toads

Question 32

what makes amphibians different from most tetrapods

Answer 32

ectotherm, unshelled eggs, aquatic stage of life cycle, gas exchange through skin

Question 33

why are amphibians affected by air and water quality

Answer 33

gas diffusion through skin - pollution can affect a wide range of its structures

Question 34

how are amniotes able to colonize land

Answer 34

no longer rely on aquatic life stage, amnion keeps embryo moist

Question 35

4 components of amniotic eggs

Answer 35

1. amnion (protection) 2. allantois (waste disposal) 3. chorion (gas exchange) 4. yolk sac (nutrients, covers yolk)

Question 36

additional adaptations of amniotes

Answer 36

waterproof skin endothermy

Question 37

examples of class reptilia

Answer 37

dinosaurs, snakes, lizards

Question 38

aquatic reptiles examples

Answer 38

turtles, crocodiles, lizards

Question 39

what differentiates reptiles from amphibians and mammals

Answer 39

keratinized skin, scales, ectothermy and endothermy

Question 40

why are birds considered reptiles

Answer 40

shelled eggs + other embryonic features

Question 41

are birds or crocodiles more closely related to dinosaurs

Answer 41

birds: crocodiles evolved after bird ancestors

Question 42

what do feathers provide

Answer 42

warmth, flight mobility

Question 43

other features of birds

Answer 43

hard shelled eggs, light bones, flight muscle attachment, lungs, no teeth, hollow bones, endothermy

Question 44

bird adaptations to challenging environments

Answer 44

beak length/shape foot structure advanced vision

Question 45

what characteristics are unique to mammalia

Answer 45

mammary glands, hair

Question 46

what features do only mammals and birds share

Answer 46

endothermy

Question 47

difference between monotremes, marsupials, and eutharians

Answer 47

Monotremes: egg laying (platypus) marsupial: young carried in a pouch (kangaroo) eutharian: embryo reaches advanced stage of devlopment before birth

Question 48

why are most mammals born rather than hatched

Answer 48

protect the offspring from predators

Question 49

why are mammals considered amniotes if they dont lay eggs

Answer 49

still have an amniotic sac (membrane around fetus = placenta)