vertebrate Flashcards
Some of the extinct Cynodonts had no what ?
lumbar ribs
what mammalian blood vessel is homologous with the 4th branchial artery in fish ?
aorta
The articular and quadrate bones are part of the cynodants jaw what are they apart of in mammals ?
middle ear
What characterises true seals (phocidae)
hindlimbs that cannot be brough forward
where did the marsupials first evolve
north america
What is an alula ?
a group of 3 feathers inserted over the first digit of the avian forelimb
What are feathers formed from ?
epidermal cells
What is the only extant species of jawless vertebrates ? and what class are they in ?
Petromyzontoidea (lampreys)
Myxinoidea (hagfish)
Agnatha
The incubation pouch of the echidna is convergent with what ?
marsupial pouch
What are PM4/M1 with regards to felids and canids ?
carnassial pair of teeth
Monotremata exhibit maternal care through ?
lactation
What interlocks in the tetrapod vertebrae ?
zygapophyses
Name a group that is paraphyletic.
reptiles
What order are goats and sheep in ?
artiodactyla
list three common features of vertebrates
vertebral column
myomeres (muscle segments)
closed loop circulatory system
list the 5 pelagic zones in order top to bottom.
Epipelagic mesopelagic (little light) bathypelagic Abyssopelagic Hadopelagic
What is the perfect shape for locomotion ? What us the length depth ratio?
Fusiform 3:7
What are the 2 sub classes of chondrichthys?
Elasmobranchs-sharks skates rays
Holocephali-ghost sharks and rat fishes
What is the main difference between the 2 sub classes of chonrichthys ?
elasmobranchs have an upper jaw that is not fused to brain case and 5-7 gills
Holocephali have a fused upper jaw with one gill slit covered by operculum
What are the two main differences between skates and rays ?
rays have reduced dorsal fin and are viviparous
What does epicercal mean and what is the opposite of this ?
The upper lobe is longer in the caudal fine.
hypocercal
what is homologous with the dermal denticle scales
teeth
how do sharks create static lift due to the lack of swimbladder ?
Cartilage instead of bone
Storage of oil (lift does not vary with pressure)
What is the spiracle used for in sharks and rays ?
Used to provide oxygenated blood to the eye and brain and in rays it is more developed allowing it to actively pump water over gills
What are the ampulllae of lorenzini ? And what do they do ?
Small pores (electrorecpetors) that form a sensory network system that are enclosed in a gel-filled tubule (glycoprotein with electrical properties) which has a direct opening to the surface through a pore. Detect weak magnetic fields from earth and fish.
What is the lateral line system and what does it do ?
allows the shark to orient to particle movement or sound.
Pores which contain neuromasts which are surrounded by a gelatinous dome.
What do the small opening in the side of sharks head and the lateral line system form ?
acoustico-lateral system
how do the few endothermic sharks regulate body temp ?
A strip of aerobic muscle which has a counter current exchange mechanism using blood vessels called the rete mirabile.
how do male sharks deliver sperm ?
pelvic claspers (modified pelvic fins) The right teste is more developed than the left. Siphon sacs forcefully inject sperm using sea water to carry the sperm.
What characterises the two sub classes of osteichthyes and what are they ?
Actinopetrygii- Ray finned
Sarcopterygii- lobe fined
What carries a growth record of osteichthyes ?
Otoliths- the shape is species dependent
Name the 4 types of scales?
Placoid (dentine and enamel)-sharks
Cosmoid (inner layer of dentine like cosmine and outer layer of vitrodentine)
Ganoid (rhomboid in shape, consist of bony basal layer, dentine and ganoine)
Cycloid and ctenoid (collagen and bony layer impregnated with calcium)
What fish have ctenoid and cycloid scales and ?what is unique about them?
most teleosts and they provide a growth record of fish.
What is the difference between physostomous and physoclistous fish ?
Physostomous fish swim bladders are connected to digestive tract so can fill by gulping air. Physoclistous fish have to secrete gas into the bladder via the blood stream.
What is the same between physostomous and physoclistous fish ?
Both have a gas gland with a rete mirabile, a counter-current multiplier arrangement of capillaries, which allows gas to be trapped in the swimbladder
What are the 3locomotory types ?
Anguilliform- sinusoidal undulations (all but head moves)
Carangiform-Posterior segments move in wave form
Ostraciform- only tail oscillates
What is a high aspect ratio useful for.
sustained swimming
what allowed the colonisation of land ?
some bony fish developed lung like sacs allowing them to breathe air temporarily.
What sub class developed jointed fins
sarcopterygii
What are the features of lobed fins ?
Fleshy paired fins attached to a single bone. Pectoral and pelvic finds resemble tetrapod limbs.
What lineage is believed to give rise to the tetrapods ?
descendants of the lungfish
What is the closest relative of tetrapods ?
And the most early ancestor of tetrapods ?
Tiktaalik roseae
Elpistostegid
What advantages does having a pectoral girdle free from the skull have ?
greater mobility allowing greater feeding
List 6 disadvantages to life on land.
need to Weight bear Development of Limbs Development of Lungs Development of Kidneys that produce concentrated urine. Cant broadcast spawn Water loss through evaporation
What is the sister group to lissamphibia ?
Temnospondyls (non aminote tetrapods)
What type of teeth do lissamphibia have ?
Pedicellate teeth- crown with base dentine. When crown breaks off it is replaced with a new one
what are the two glands in amphibian skin ?
Mucous glands maintain moist skin for respiration.
Granular glands produce toxic secretions.
What is unique about amphibian hearing ?
Have a 2nd amphibian papilla 200-800Hz as well as basilar papilla 1200-1600Hz
What are the 4 photoreceptors in amphibian eyes ? And what is the 5th receptor that only some amphibians posses?
Red rods contain rhodopsin (green wave length0
Green rods-unique (blue wavelength)
single cones (yellow wavelength, 580nm absorbance)
Double cones- two fused cones (yellow wave length and rhodopsin)
3rd rod cell that contains porphyropsin which responds to PURPLE
What are urodela and what are some key features ?
Salamanders and newts
Paedomorphosis (retention of juvenile features)
Precise courtship ritual for spermatophore transfer
Frog and toads belong to anura what does anura stand for
without tail
What two character complexes allowed full land colonisation.
Amniote egg
Traits that reduced water loss such as apomorphy (skin impermeable to water) and plesiomorphy (concentrated urine)