Zoology week 5

Question 1

Chordata

Answer 1

Deuterostomia phylum: dorsal nerve chord, notochord, postanal tail, endostyle/nerve chord, pharyngeal slits

Question 2

Craniata

Answer 2

chordate subphylum: skull surrounding brain, olfactory organs, eyes + inner ear

Question 3

Fish

Answer 3

span both craniata, closed circulatory system with a heart and haemoglobin, gills, kidneys, brain and spinal chord

Question 4

Agnatha

Answer 4

Clade of jawless fish

Question 5

Hyperotreti

Answer 5

Craniata infraphylum: hagfish, no vertebrae, notochord retained in adulthood, sensory tentacles around mouth, slime glands

Question 6

Vertebrata

Answer 6

Craniata infraphylum: vertebrae surround nerve chord

Question 7

Ostracoderms

Answer 7

Vertebrate class: extinct fish with endo and exoskeletons, jawless agnathans but used eco-plates in jaw like fashion

Question 8

Petromyzontida

Answer 8

Vertebrate class: Lampreys, agnathans, no paired appendages, cartilage skeleton, sucker-like mouth, raspy Tongue and keratin teeth (larva filter feeders, adults mostly parasitic)

Question 9

Gnathostomata

Answer 9

Vertebrate superclass: includes all jawed vertebrates

Question 10

Chondrichthyes

Answer 10

Gnathostomata class: sharks, rays and ratfish: no operculum (except ratfish), cartilage skeleton (not bone), placoid scales made of dentin and enamel, teeth are modified scales, tails are whip-like or heterocercal

Question 11

Osteichthyes

Answer 11

Superclass(?): have operculum, lungs and/or a swim bladder

Question 12

Sarcopterygii

Answer 12

Osteichthyes class: have lobed (fleshy) fins, gave rise to tetrapods: homocercal tail and operculum

Question 13

Actinopterygii

Answer 13

Osteichthyes class: delicate, boneless fins, homocercal tail and operculum

Question 14

Amphibia

Answer 14

Paraphyletic class within vertebrata: hairless, scale-less skin that secretes mucus, aquatic larvae that undergo metamorphosis, 2 heart chambers, 1st terrestrial vertebrates but need to stay close to water

Question 15

Amniota

Answer 15

monophyletic group including reptiles, birds and mammals, have an amniotic egg adapted for terrestrial environments with an extra embryonic membrane to protect from desiccation, cushioning, promote gas exchange and store nitrogenous waste

Question 16

Synapsid

Answer 16

mammals, 1 temporal skull opening

Question 17

Anapsid

Answer 17

extinct reptiles, no openings

Question 18

Diapsid

Answer 18

Living reptiles (including birds), 2 openings

Question 19

Reptilia

Answer 19

Vertebrate class: Skull with 1 smooth surface (condyle) for articulation with neck vertebrae, lungs and kidneys, watertight skin with keratin scales

Question 20

Aves

Answer 20

Vertebrate class: Descended from reptilian ancestors, Adapted for flight (wings, feathers, endothermic and high metabolic rate), light/hollow bones, horn-like bill with no teeth, uric acid

Question 21

Mammals

Answer 21

Vertebrate class: descended from earlier branching reptiles than birds, synapsid, mammary glands, hair, diaphragm, 3 ear ossicles, 4 chambered heart

Question 22

Protetheria

Answer 22

Mammalian subclass: earliest diverging mammals, are oviparous (lay eggs), platypus and echidna

Question 23

Theria

Answer 23

Mammalian class: 2 infraclasses, metatheria (marsupials) have a short gestation period and pouches for underdeveloped young: Eutheria (placental) have longer gestation and more developed young

Question 24

Urochordata

Answer 24

Chordate subphylum: tunicates/sea squirts: larvae free living and have all 5 chordate characteristics, adults sessile, only retain pharyngeal slits and endostyle, filter food with incurrent and excurrent siphons

Question 25

Cephalochordata

Answer 25

Chordate subphylum: lancets: show all 5 chordate characteristics, tadpole-like (elongate, flattened and nearly transparent) usually filter feed in sediment