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)
What are the 4 embryonic membranes in an amniote egg?
Amnion: surrounds embryo itself (protection)
Chorion: surrounds embryo and yolk sac (gas exchange)
Yolk sac: surrounds yolk that nourishes the embryo
Allantois: evolved to store nitrogenous waste and aid gas exchange between embryo and egg surface
Give an example of an anapsid synapsid and diapsid
Turtles-no temporal fenestra
Mammals- 1 temporal fenestra
Snakes, birds- two temporal fenestra
What does the sauropsids (lizard like reptiles consist of)?
Anapsids: testudines
Diapsids: Archosaurs (dinosaurs, crocodiles, birds), lepidosaurs(lizards snakes).
What are the key features of testudines?
vertebral column and ribs fused to carapace.
temperature dependent sex determination (cold for males)
What are the 2 groups within testudines ?
Cryptodires= verticle head retraction (turtle) Pleurodires= horizontal head retraction (matamata)
How is the snakes jaw adapted for feeding ?
skull with 8 flexible links asymmetrical kinesis (one side of skull can move independently)
What are the 4 types of snake locomotion ?
lateral undulation
rectilinear (move with scales)
concertina
side winding (limited contact with ground)
What are the 3 venomous snake morphologies ?
Opisthoglyphous: “back-fanged”, one or more enlarged teeth near rear of maxilla, may have groove to inject saliva
Proteroglyphous: hollow fangs on front of maxilla, permanently erect, short teeth behind
Solenoglyphous: only teeth on maxilla are long hollow fangs, maxilla rotates to allow jaw closure
What do flight feathers consist of and what are they used for ?
Primary feathers attached to hand bones for power
Secondary feathers attached to ulna for lift
What type of feathers cover the body and what type create insulation ?
Contour feathers
Down feathers
What feather fills in the gap between contour and down feathers ?
Semiplumes.
What are the arrangements of feathers ?
Pterylae- Contour and flight feathers going down body and wings.
Apteryia: in between spaces, down and semiplume feathers
What does the uropygial gland do ?
Produces waxes fatty acids and water to coat feathers and clean them.
What is the order of moulting for body and flight feathers ?
Body feathers moult from dorsal tract outwards
Flight feathers moult from primary feathers outwards to secondary.
What stimulates migration ?
changes in photoperiod.
What does an increase in thyroid hormone induce in birds?
Moulting
What defines the nodes in a cladogram?
Synapomorphies (shared derived character states)
What did cynodonts develop allowing them to eat and breath ?
A secondary palate creating a nasal passage.
What is the distinguishing feature that separates cynodonts from mammals ?
Squamosal jaw bone=hinge
What separates the monotremes from the marsupials?
tribosphenic cheek
In the mammalian ear what bones are homologous with cynodont jaw bones ?
Malleus is homologous with articulate
Incus is homologous with quadrate
What are the two types of monotremes ?
Echnida
platypus
H\ow are marsupials distinct from monotremes ?
Testes in scrotum instead of internal
Seperate anus and urinogential sinus instead of dual function cloaca
What are the types of teeth shown in mammals ?
Bunodont- Flattened for crushing
Lophodont- Rigid grinding with cement, dentine and enamel all exposed
Hypselodont-open rooted
Seledont-crescent shaped molars
Sectorial-Cheek teeth used for slicing
Incisors- open rooted with enamel either side.
What is the plantigrade stance ?
feet on ground, with flexion at wrist/ankle.
What type of stance has metatrsi and carpi off ground ?
Digitigrade
What are the two types of unguligrades ?
Perissodactyla: odd-toed ungulates
Artiodactyla: even-toed
What stance does the elephant have ?
Graviportal
What is a pro and con of water as a medium
Water is more viscous therefore more energy is needed to move through it.
Water is more supportive therefore less energy needed to support a body
How do you age odontoceti and mysticeti
Tooth growth layers
Ear plug growth layers
What are the phocenidae ?
Porpoises
Are mysticetes animals that travel in groups and do they represent sexual dimorphism ?
No groups apart from humpback whales and they show reversed sexual dimorphism
What are known as the roquals ?
Balaenopteridae
What are the 3 types of groups in killer whales ?
Resident groups
Pelagic
Transient
What are the advantages and disadvantages of being in a group ?
Protection against predators
Easy to find mates
Cooperative foraging
Competition for prey
Risk of inbreeding (if all breeding occur within the group)
Risk of extirpation if subjected to large scale mortality event
What are the 3 families within the order pinnipeds ?
phocidae-True seal (fixed hind flippers deep divers)
Otarriidae- Fur seals (can walk)
Odobenidae- walrus
What is unique about the hair of the otariidae ?
Has 2 layers an outer protective layer and an inner layer of soft underfur for warmth. Phocids and obobenidae have blubber instead of inner layer.
What do the hooded, harbour and bearded seals all do that reflects a secondary adaptaion to breeding on land?
The lanugo is moulted in the uterus.
Why is the distribution of pinnipeds limited towards the equator ?
Inability to thermoregulate
What is unique about pinniped reproduction ?
Have a delayed implantation of embryo due to gestation taking 7 months and breeding being annual.
What are the features of a featureless sea ?
Costal upwelling
Bathymetry
Temperature fronts
Eddies
What is a dive bout and dive cycle.
A group of dives
Surafce time+ dive time
What constraints act on diving behaviour ?
Light levels
Predators
Diving ability
What are the 5 dive shapes and what do they show ?
Hard square-benthic divers soft square- coming to dive limit V shaped- prey within water column, can also show unsuccessful dive Skewed right- negatively buoyant Skewed left- positively buoyant
What does surfactant do ?
Reduces surfaces tension and allows surfaces to come apart after collapsing.
Why do marine vertebrates exhale before diving?
To enhance lung collapse and reduce buoyancy
What is the role of the spleen ?
The spleen is a store of oxygenated red blood cells that when collapsed due to pressure provides cardiovascular system with blood.
What is the benefit of being larger ?
Increased volume of red blood cells.
What adaptations allow long dive periods ?
Increased tolerance to hypoxia
Redistribution of blood
Reduced heart rate
Efficient swimming
What is ADL and how is calculated ?
Aerobic dive limit is the max duration an animal can sustain aerobic metabolism.
Calculated from 2 factors:
Useable O2 stores
Metabolic rate
What is better one long diver or multiple short ?
Multiple short as long dives require large recovery periods 60min dive= 100min recovery
20min dive= 2 min recovery
If the lactate is oxidised or is recycled back into glucose what does this do to recovery time and what is this process called ?
Gluconeogensis
Increased recovery time or decreased dive time.
What are 4 characteristics of chordates ?
Notochord
A dorsal chord
Bilateral symmetry
Pharyngeal pouch
What are the 3 subphyla in chordates ?
Urochordata-tunnicates
Cephalochordata- lancelet
Vertebrata
What is a key trait of agnatha ?
no paired fins
What are batoids ?
Flat bodied elasmobranchs such as skates and rays. Pectoral fins developed into broad flat wing.
What is the dorsal fins primary function ?
anti roll and defence if spiked or has glands
What does homocercal mean ?
symmetrical caudal fin
How is a sharks age measured ?
Growth ring from vertebrate radiocarbon dating.
What is unique about shark teeth ?
Teeth not permanently lodged into jaw they are on a membrane that acts as a conveyor belt replacing lost ones.
what are the 3 features of osteichyes ?
Bony skeleton
Hinged jaws
Operculum
What is the peduncle ?
The point of which the caudal fin arises.
How does the rete mirabile counter current system work in swim bladders ?
The pH of blood is changed to vary how much oxygen is in the blood. High pH allows more oxygen.
How do ostraciform swimmers swim ?
Contract on side of the body and then the other in order to move caudal fin.
What are the advantages to terrestrial life ?
Escape predators
new food source
Easier to access O2
How does the buccal pump work ?
Come to surface and close operculum and open mouth.
Depress buccal floor thus increasing volume allowing air in.
Close mouth and buccal pump forces air over lungs
What are 2 key features of amphibians ?
Cutaneous respiration
No diaphragm
What are the 3 pigment cells in amphibia ?
Melanophores-black reddish
iridophores- reflect light
xanthophore-yellow orange
How do adult frogs care for young ?
Young often attached to male or mouth brooders
What Does the order saurishcia contain ?
Theropods (carnivores/birds)
Sauropodomorphs
What type of feathers are known as neossoptiles ?
Down feathers
What type of feathers are used as pressure receptors ?
Filoplume feather
In cynodonts what allowed a stronger bite ?
Zygomatic arch
In marsupial foetal development what type of yolk sac is formed ?
Chorioviteline yolk sac
Why do pinnipeds reduce heart rate during dive ?
So the O2 in muscles is utilised.
What are the 5 types of snake venom ?
proteinases (tissue destruction) hylauronidases (tissue permeability) amino acid oxidases (tissue destruction) phospholipases (cytolytic) polypeptides (neurotoxic)
What does the swim bladder wall contain that makes it impermeable to gas ?
Guanine crystals
What adaptation allows sharks to be isotonic ?
Contain high concentrations of urea and trimethylamine N-oxide
