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235 Cards in this Set
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- Back
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In cnidarians, in general the polyp is smallest and least complex in...
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Hydrozoa - they're the really small stalky things
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Glass sponges belong to the class...
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Demospongiae (silaceous spicules, not 6 rayed though)
Hexactinellida (6 rayed = venuses flower basket) |
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Calcaerous sponges belong to the class...
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Calcaera!
have the classic 3 rayed spicules |
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What is a nematocyst?
and what is it discharged by? |
Stinging organelle in cnidarians,
by osmotic pressure |
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Acontia - what are they?
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in sea anemones - the edges of the septa that extend into thread like structures that have nematocycst and stuff inside them
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sexual reproduction in sponges - where do sperm arise from?
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choanocytes - the flagellated cells that generate water flow through the sponge
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leuconoid sponges - are the channels into the sponge lined with choanocytes?
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No, only the chambers in the sponge, these chambers with choanocyes create the current that draws in the water
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most sponges are ....... in structure
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Leuconoid, the most complex type, also the most efficient. 80-90% of sponges are in the class demospongiae
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athropod exoskeleton evolved in the .... period
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precambrian
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athropod deuterostome or protostome?
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protostome (so schizocoely)
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exoskeleton of athropods made of?
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chitin and protien
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layers of athropod exoskeleton from surface down... GO
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Main ones: epicuticle, procuticle, epidermis.
(within procuticle - exocuticle and endocuticle) |
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Procuticle - function
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strength = cross linking (chelicerates, insects)
embedding of calcium salts (crustaceans, why their outside is so tough) |
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epicuticle - function
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chemical barrier - complex mix of protiens and waxes = waterproofing
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moulting - where is moulting fluid secreted, what layer?
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below endocuticle, but most of the good bits like chitin and calcuim salts have been rabsorbed by this time
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homonomy
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primitive kind of tagma where each has a pair of jointed appendages, each segment is functionally similar
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heteronomy
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where the jointed appendages are highly specialised for different things, eg crustaceans
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tagma
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many segments fused together in a functional group - eg in spiders the abdomen is many bits fused together
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what has BIRAMOUS appendages
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trilobites and crustaceans
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tracheal system - one adv. one disadv.
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O2 direct to tissues = good for periods of intense activity
limits body size |
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hemimetabolous
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has nymph stages, gradual changes
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mandibulata - name 2 of the three sub phylum
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myriapoda (centipede, millipedes)
Hexapoda (insects) Crustacea (crustaceans) |
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what's special about those huge trilobite eyes?
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compound eyes had calcium carbonate lens - c.f protein one of modern arth.
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when were trilobites dominant?
When extinct? |
mid cambrian (remember the athropod exoskeleton came about in pre cambrian)
extinct 225 MYA |
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SubP Chelicerata name one
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Class Arachnida,Merostoma (horseshoe crabs), Pycnogonida (sea spiders)
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SubP Myriapoda, name the 2 classes
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Diplopoda = millipedes Chilopoda = Centipedes |
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Super class Hexapoda, classes?
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= class insecta ... All of those insects...
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SubP Crustacea, name 2 classes
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Class Maxillopoda (copepods, Barnacles)
Class Malacostraca = Crabs, Shrimp, Crayfish, slaters |
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protopod, which part?
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main bit that the other exopod and endopod extend from |
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exopod
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the one on the outer side of body
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endopod
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closest to body
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epipod - in crayfish what function?
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outgrowth of the protopod - often modified as a gill eg in crays
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how is exoskeleton of athropods different to shell of molluscs?
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ath. is more alive - has sensory hairs and glands poking through
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gill chamber - where?
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= between body wall and carapace- where the gills can sit nice and safe
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layers of crustacean exoskeleton
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pigmented layer and calcified layer. No waxy coating
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in moulting, when does the secretion of the new endocuticle occur?
the epicuticle and exocuticle? |
endocuticle - in postescdysis (after old epicuticle and exocuticle have been shed)
epicuticle = in premoult exocuticle = in second part of premoult |
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what causes moulting
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1 env. stimuli makes CNS secrete less MIH from X organ in brain
3 Y organ near mandibles releases MH in response to low MIH |
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main body cavity in crustaceans is?
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Haemocoel - leftover from blastocoel = open circulatory system
Reduced Coelom |
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pericardial sinus
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chamber outside heart, 'blood' reenters heart from here via ostia
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blood pigments in crustaceans
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heamoglobin, heamocyanin
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do crustaceans have veins?
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NO, blood returns via sinouses after going through the gills
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thoracic gills
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just means have gills in a pocket in thorax
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how does water get into gill chamber?
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Bailer - part of 2nd maxillae fans it in
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digestive system in crus.
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one-way, tubular gut
complex stomach in some different kinds of 'tooth' and filters to sort food |
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excretory sys in crus.
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paired nephridia in head
oft. called green glands, antennal or maxillary glads nitrogen excreted as ammonia |
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class remipedia
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primitive crus. swim on back, 2 tagma
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class branchiopoda
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water fleas, Anostraca - brine and fairy shrimp,
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class Ostracoda
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seed shrimps, have paired shell, benthic,
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Class Maxillopoda - which phyla? sup phylum? give one example
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barnacles, legs used just for feeding
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Class Malocostrata, give one eg
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crabs, shrimp, yabbies (has isopods = eg. slaters dorsoventrally flattened, no carapace) order decapoda = 10 legs
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isopods have a carapace?
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NO (are pill bugs and slaters)
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first three pairs of appendages in crays do what? are found where?
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Are maxillipeds and with maxillae are used for food handling. found on THORAX
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what do water fleas and other members of Claudocera use their antennae for?
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Swimming and feeding
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What do branchiopods use their feet for?
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branch = lung pod=foot
they use them for respiration |
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ALL athropods have an ..... circulatory system
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open
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Chelicerates:1st and 2nd pair of appendages = what? + how many walking legs?
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1st = chelicerae
2nd = pedipalps 4 pairs |
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What's special about order Acari (mites and ticks)
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cephalothorax and abdomen fused - have gnathosoma and the rest is idiosoma (which is the fused cephalothorax and abdomen)
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Order Araneae
Mygalomorphae |
fangs point straight down and don't cross each other
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Aranaeomorph spider
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Fangs bite at right angles to body in a pincer like action, they cross each other = most spiders
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book lungs
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in spiders and others
many parallel air pockets that extend into blood-filled chamber, air goes in via slit in body wall and oxygenates blood |
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myriapods - how many body segments? name five parts of head
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2 - head and trunk(with many legs)
1. antennae 2. mandible base? 3. mandibles 4. maxilla one 5. maxilla 2 |
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diplosegments in millipedes
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two segments that have fused and so have 2 pairs of legs, ie 4 legs all up
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which of the myriapods has fangs?
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chilopods (centipedes. bc they are predators)
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hexapoda - name the general characteristics
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3 body tagmata - head, thorax, abdomen. 3 pairs legs (hex=6, pod=foot). usu. 2 pairs of wings
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Apterygota - what are they?
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= wingless insects = eg. silverfish
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pterygota - what are they?
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= winged insects |
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Paleoptera
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ancient wings = thought to be most similar to ancestral condition, can't fold wings eg dragonflies
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neoptera
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new wings, can be properly folded, everything except dragonflies, mayflies (paleopterans)
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exopterygoa?
what kind of dev? |
outside wings - look at the 'ex' prefix
have HEMIMETABOLUS dev (cf catterpillars. wings are inside until go through last moult/cocoon stage) |
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endopterygota
what kind of dev? |
inside wings,
HOLOMETABOLOUS dev (= nymph stage and gradual growing up with each moult) |
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Orthopteroid orders (P arthropoda)
eg.? what kind of mouthparts what kind of pterygota? |
eg. grasshoppers, mantids, termites
hard biting mouthparts exopterygota |
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Hemipteroid orders
eg? what kind of mouthparts? what kind of pterygota? |
aphids, cicadas, backswimmers
piercing and sucking mouthparts |
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what is the hard covering on true beetles formed from (what structure)? what's it called?
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wings - forewings modified to be hard protective covering
Elytra |
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in 2 winged flies, what is the hind wing modified into?
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halters for stability
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what is the stinger of a bee modified from?
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ovipositor. worker bees don't breed so don't need an ovipositor
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bees, ants and true flies: Endopterygotes or exopterygotes?
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endo
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hexapods: name 2 things that constrict their size.
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trachea, inefficient the bigger you get
Moulting, you're very vulnerable to predation when you don't have your armour Support: |
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characteristics of Hexapods cf crustaceans - head end esp.
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different = uniramous appendages, ONE pair of antennae, 3 pairs jointed thoracic legs Same as crus = pair of mandibles and 2 pairs maxillae on head,
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name four stages for homometabolous life cycle and what each stage is about
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1. egg:protective 2. Larvae: feeding and growth. 3. Pupae: protection for transition to adult. 4. Adult: reproduction, spreading out and occupation of different niche
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name three things that make flight possible in Hexapods
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organised muscle system, high met rate, small size, flexible thorax
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how many head segments in hexapods? name in order
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1. antenna 2. - 3. mandible 4. maxilla 5. labium
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excretory system of hexapods? what kind of nitrogen?
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malphigian tubules, secrete uric acid = uses v little water
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digestive sys of hexapods
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foregut = before gastric caeca, midgur = btw caeca and malphigian tubules, hidgut = after malphigian tubules
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what is peritrophic membrane in hexapods?
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surrounds food bolus in midgut
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hexapoda - saprophagy
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= eat dead, decaying organic material
eg cockroaches, flies |
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hexapoda - phytophagy
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= eat things from plants - nectar, pollen, sap
eg. grasshoppers, aphids |
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hexapoda - hematophagy
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parasites, don't kill host, usu. only one life stage, eg. fleas, mozzies, lice
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in deuterostomes what does the blastopore become? in protostomes?
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deut = anus. protostomes = mouth
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deuterostomes - what is coelom formed from?
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mesoderm that arises from invagination of the endoderm
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circulatory sys in molluscs
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open (except for cephalopods bc they're very active), haemocoel is blood-filled body cavity
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mantle cavity - what exactly is it?
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Open space surrounded by mantle tissue, contains ctenidia or other breathing aparatus
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molluscs - ectocochleate and endochochleate
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means shell on outside vs shell on inside (eg. most extant cephaopods)
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cephalopods sensory organs
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eyes, very good eyesight
chemoreceptors on head |
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how do bivalves produce their water feeding currents
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cilliary action
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scaphopods cf bivalves
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use cilliary AND muscular action to create water current, HAVE radula, gills ABSENT (just use mantle?)
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primitive gastropods reproduction
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EXTERNAL fertilisation -> trochophore -> veliger -> metamorphosis and settlement.
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advanced aquatic gastropods - reproduction
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internal fert -> egg mass/ capsules -> veliger -> metamorphosis NO free swimming trochophre stage
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reprod of advanced land gastropods cf aquatic ones
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NO free swimming larvae (trochophore or veliger) - even in aquatic species. Baby snails hatch
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cephalopods reproducton
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direct egg dev in capsules, baby cephalopods (eg baby squid) hatch
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Bivalves reproduction
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external fert. trochophore and veliger larval stages, some end up hermaphrodites, some brood eggs
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Ecdycozoa - what are they?
give 2 examples |
Have external skeleton, and moult it to grow
nematoda, all arthropods( so trilobites, chelicerates, myriapods, crustacea, hexapods etc.) |
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Lophotrochozoa - two groups, name them
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Trochozoa = ALL have trochophore larvae, though they end up looking vey different (it's that triangular-prisim like blob thing with cillia on the top, around the sides.. anus at bottom)
And LOPHOTROCHOZOA - have lophophore for feeding |
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lophophores - what kind of body plan? name one distinguishing feat.
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triploblastic coelomate
have lophophore = crown of tentacles around mouth both deuterostome and protostome features |
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Phylum Phorondia - name one dist. feat.
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Are marine, worm like filter feeders,
have lophophore - tentacles around mouth |
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P Brachiopoda - what are they?
cf bivalves |
Marine , 'lamp shells', filter feeders, dominant 550-250 mya, only 350 species left today
dif to bivalves bc use lophophore tentacles to feed (not ctenidia) |
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P Bryozoa - what are they?
2 things |
Coelomate, mostly marine (some fresh), colonial - zooids prduced by asexual budding
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P Bryozoa - 2 types of lifestyles/structures
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Aborescent and encrusting(oft on the bottom of ships)
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How is the lophophore of a bryozoan pushed out of its little box?
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coelomic pressure forces it out, each zooid has a crown of these tentacles
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P Echinodermata
3 dist features |
calcaerous ENDOSKELETON (on inside), Pedicellariae, water vascular system, dermal branchiae, oral and aboral surface
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is water vascular system in echinderms a part of the coelom?
what's it filled with? |
yes
coelomic fluid |
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what are the external projections, used mainly for movement, in echinoderms called?
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podia - tube feet
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echinoderms - what are papullae and what are they used for?
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also known as dermal branchiae - they are soft projections that stick out between the ossicles to the outside and are used in respiration
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echinoderms - catch collagen
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collagen between the ossicles that can be stiffened with nerve impulse so starfish etc. goes rigid
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pedicellariae
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little tiny pincers on the outside of the starfish, they help keep surface free of debris, protect papullae and sometimes help with catching food.
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in echinoderms - ectoderm noncilliated or cilliated?
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cilliated
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madeporite
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the pore that lets water in and out of the water vascular system
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polian vesicle
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bubble bit on ring of water vascular system, not in all sea stars though
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Tiedemann's bodies
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little pouch like bits on ring canal of water vascular system in echinocerms
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echinoderms - reproduction
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External fert. - one or more larval stages(free floating then attach to surface) - metamorphosis
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are the larvae of echinoderms radial or bilateral?
adults what kind of symmetry |
Bilateral,
pentradial |
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Class asteroidea
What Phyla? what are they? 1 feat. |
Sea stars
echinodermata usu. 5 arms, ambulacral grooves along each arm (tube feet in groves for locomotion) disc on oral surface but it's not pronounced |
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Class Ophuroidea
What phyla? 1 feat. what do they lack that sea stars have? |
Brittle Stars
echinodermata jointed flexible arms used for locomotion, pronounced central disk, NO AMBULACRAL GROOVES or pedicellariae |
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Class echinoidea
phylum? one feat. |
sea urchins
echinoderms aristotles lantern, spherical - arms folded up into a ball (oral surface is outside) long spines |
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how do brittle stars respire?
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Have 5 pairs of bursae - invaginations that open to the outside by bursal slits on the ORAL surface
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Class Holothuroidea?
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= sea cucumbers
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Class Crinoidea
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Sea lillies and feather stars
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when did metazoans originate (about)
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colonial flagellated protoozoa
700 MYA in Precambrian |
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when and what was cambrian explosion
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600 MYA
all major body plans were established, explosion of different animals |
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2 things that caused cambrian explosion
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Ecological, geologic, genetic (mutations in Hox genes),
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Tissue organ organisation - which animals
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the middle bit of the phylogeny tree... the nemertans, flatworms and nematodes(?)
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cell tissue organisation
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cells are organised into distinct tissues - eg jellyfish and other cnidarians
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what's the downside to cell specialisation?
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greater vulnerability to injury - if a bit gets cut off can't as easily live
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are multicellular organisms more or less energy efficient than their single celled counterparts?
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less, milticellular organism (protozoan)are quite inefficient, BUT there are things like efficiencies of scale,avoidance of predation and specialised parts of body that make it worth it
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eumetazoa - what are they?
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all the multicellular animals EXCEPT SPONGES. Eumetazoa have germ layers and TRUE TISSUES, a digestive cavity and a mouth
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how does a sponge digest food?
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each cell digests food particles individually
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are sponges old/young in evolutionary terms
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Ancient - 700 MYA
also very diverse |
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the osculum is where the water goes ___in sponges
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out - excurrent canal
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what do porocytes and ostium in sponges do?
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let water in - the porocytes surround the opening(the ostium)
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what do choanocytes do?
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are flagellated cells that create water current in sponges
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outer layer of cells in a sponge called what?
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Pinacoderm = pinacocytes (body wall cells) and Porocytes (cells lining the pores / ostium)
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choanoderm contains which cells?
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choanocytes, for creating water current in sponges
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Archeocytes
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Are free moving, totipotent, amoeboid cells that move around and do lots of things. totipotent = Can specialise and UNSPECIALISE which is weird and rare and strange
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how do sponges reproduce?
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mostly, when times are good, via asexual budding
when times are bad - sexually, sperm carried to nearby sponges where it fertilises eggs. Free swimming larva goes off and finds a new place to colonise |
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do sponges have gonads?
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no.
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Which is the best way to classify sponges ( most accruate in evolutionary terms)
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By cell wall type and spicules
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Asconoid sponge
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Simplest - tube lined with choanocytes
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Synconid sponge
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Middle one - foldings of the body wall lined with choanocytes
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Leuconoid sponge
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most complex - incurrent canals lead to flagellated chambers lined with choanocytes
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No pinacoderm (is Syncytial) -what kind of sponge is it?
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Hexactinellida - venus's flowerbasket one
silaceous spicules |
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is Cellularia (has pinacoderm) - what kind of sponge, what classes?
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Calcarea - calcarous spicules
Demospongiae - silaceous spicules |
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the only non - eumetazoan animals are ....?
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sponges
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what kind of cellular organisation do cnidarians have?
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cell - tissue level
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what kind of muscles do cnidarians have?
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epitheliomuscular cells - longitudinal and circular
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where are nerve cells in cnidarians located
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below epidermis, near mesoglea
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what kind of sensory structures do cnidarians have?
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can perceive touch and chemicals
specialised recetors at specific sites |
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cnidocysts in cnidarians
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contain nematocysts and used for prey capture
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cnidarians -reproduction
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alternating generations - usu. asexual polyp and sexual medusae form
all have a free swimming stage sexual forms are dioecious |
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Class Anthozoa
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Sea anemones and corals
don't have medusae, asexual and sexual |
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how do polyps differ from hydrozoans?
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have mesentries, mesoglea has amoeboid cells, mouth leads to pharynx
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zooantharia (hexacorralia)
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anemones and most corals
have mutalistic zoxantellae algae |
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which corals have interconnection between the polyps
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octocorals / Alcyonnarian corals - soft and hard corals
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Class scyphozoa
which is dominant stage? |
true jellyfish, medusae is dominant
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Strobila stage in jellyfish
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fixed to substrate, lost in some, free swimming ephyra breaks off and becomes jellyfish
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class Hydrozoa - features, what kinds?
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mainly colonial, eg portugese man o war, obelia
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Phylum Ctenophora cf other jellies
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comb jellies, true muscular system (antagonistic), getting towards radial symmetry - biradial
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2 adv of a body cavity
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more room for organs, more SA for diffusion of gasses, nutrients etc., storage area, oft. a hydo skeleton, helps w increased body size
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foregut, midgut, hindgut - which are ectodermal? endodermal?
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the midgut is endo, rest are ecto
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phylum platyhelminthes - 3 things they have
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bilateral Symmetry, acoelomate (mesenchyme is 'stuff' between endo and ectoderm), single opening to gut, free living (turbellarians) parasitic (the rest)
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Nemerteans - 3 things
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dorsovent flattened,
through gut with anus most freeliving and predators, cephalized |
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free living forms of platyhelminthes have what on outer layer
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cilliated epidermis
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parasitic forms of platyhelminthes have what on outer layer
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non-cilliated syntical (many nuclei, one cell) tegument, helps evade host's detection
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platyhelminthes what kind of excretory system
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protonephridia - flame cells
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platyhelminthes - what kind of NS?
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have brain, longitudinal nerve cords, eye spots, statocysts
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class monogea, class trematoda, class cestoda
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first 2 are flukes,
tapeworms |
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turbellarians reprod
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asexual - fission, cut them in half and they grow back
sexual - hermaphrodites, usu cross fertilise. penis fighting |
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what is body mainly filled with in flukes?
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reproductive tissue
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what is the definitive host?
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where the parasite is mature and reprod SEXUALLY
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intermediate host
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where parasite develops and reprod ASEXUALLY = an increase in parasite without the need for sex
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general life cycle of a trematode (chinese live fluke)
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egg, miracardium (cillated larvae), sporocyst (M becomes this in I host), rediae(after asex reprod become this), cercariae (more asex reprod makes this)
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do suckers on cestodes have hooks? what about on trematodes?
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Yes
No |
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nematodes - what kind of digestive sys? cavity?
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through gut (mouth and anus)
Pseudocoelomate |
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one def feat. of nematodes
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non living protective cuticle
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nematodes - respiration
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no special kind of system, get all they need from diffusion as they're quite small
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nematodes reprod
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doiceious, sexual dimorphism, hermaphroditic(ovitestis), parthenogenisi - sperm stimulate egg but no genetic material exchanged,,,weird
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nematomorpha and nematodes both have which kind of muscle
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longitudinal only! = non directed movement
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rotifers - part of what clade?
body plan? reproduction? |
gnathifera - all have muscular pharynx with hard jaws
pseudocoelomate flexible reprod, |
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do molluscs have a body cavity?
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yes, but it's reduced to a cavity around the heart (pericardial cavity)
main body cavity is the haemocoel which is filled by haemolymph and is the open circulatory system |
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what secretes the shell and also contains osphradia in molluscs?
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the mantle
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what supplies haemolymph the the ctenidia in molluscs?
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the heart
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what is the radula made of?
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keraitn, is very tough
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molluscs excretory sys?
is it water efficient? |
nephridium - pericardial space (coelom) collects urine and it's exreted via the renopericardial canal - uses lots of water ~live in wet environs
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molluscs NS
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nerve collar in foot
lots of gangila around body can be V highly developed |
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trochophore larvae
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mollusc larvae (and annelids?)
is planktivorous |
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Class poluplacophora
describe shell describe ctenidia |
Chitons, 8 plated shell, Pallial groove (mantle cavity) contains many leaf-like ctenidia
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Class Monoplacophora
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old, mainly fossil group, repeated organs (possible link to annelids/segmented worms) eg 6 pairs nephridia, 5-6 pairs ctenidia, 8 pairs retractor muscles
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class gastropoda
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the SNAILS also limpets, slugs,
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3 feat of gastropoda
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Calcareous, COILED shell, torsion (180degree body twist during trochophore larva dev = head and anus end up beside each other)
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sub class prosobranchs
respiration? |
most gastropods are these, RESPIRE with leaf like ctenidia, incurrent and outcurrent flow are separated
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Sub class opisthobranchia
respiration? |
Aquatic slugs and nudibranchs,
shell and mantle cavity reduced or absent ctenidia replaced by folded external gill(the fluffy bit atop nudibranchs) |
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sub class pulmonata
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no ctenidia, vascularised mantle for breathing air
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metamerism
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segmentation, repeated segments
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segmentation. pros - cons
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pro - increases effectiveness of coelom for movement
con - decreases efficiency fo diffusion ~need circ sys |
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prostomium
pygidum |
has brain and sense organs
segment with anus |
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chaetae
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ANNELIDS only. made of chitin, can be attached to parapodia
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Annelida circulation
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closed haemal system
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excretory sys of annelids
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similar to molluscs, nephridia grouped tog into METANEPHRIDIA
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annelids reproduction
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clonal and sexual
spawn via metanephridia trochophore larvae (like molluscs, evidence of shared ev history) |
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Class Polychaeta
2 things that distinguish |
Well dev head and sense organs cf other classes,
each segment has pair of biramous parapodia (well primitively, some have lost them) variety of feeding modes mobile (errant) or sedentary |
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Class oligochaeta
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= few bristles
earthworms, NO parapodia, ARE hermaphroditic, Mainly terrestrial or freshwater, small single or double bristles - chaetae, Glandular clitellum that secretes egg cocoon |
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Class Hirudinea
3 things to define |
the LEECHES. EW.
Clitellum, 1or2 suckers, hermaphrodite, carnivorous or ectoparasitic, FIXED number of segments, terrestrial or freshwater |
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leeches that attack mammals have... (name 2 things)
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anaesthetic, anti-clotting agent, histamine to promote blood flow, antibiotics against foreign bacteria = which is why hospitals still use them!
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Phylum Onychophora
What? name 2 dist feat. |
paired appendages on each segment, segmentation of some systems (eg NS), Simple brain, thin cuticle, MOULTS, MANDIBLES, TRACHEAE - last 3 are like arthropods
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what features to onychophorans share with athropods? with Annelids? name 2 from each
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Annelids: segments, wormlike body, simple brain, thin cuticle,
Athropods: Moults? Mandibles, tracheae |
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Phylum Tardigrada
2 things |
Coelomate, protostome, water bears
aquatic or moist environments, simple brain, through gut, capable of cryptobiosis |
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what are tentacles in Class holothuroidea used for?
how do they breathe ? |
= sea cucmbers, used for feeding, respiritory tree for breathing (unique to echinoderms)
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in class crinoidea what are the tube feet used for?
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feeding only!
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Phylum Hemichordata
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thought to be chordates then that was revised. have proboscis, collar trunk - those worm-like things
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5 chordate things
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dorsal tubular nerve cord, notochord, pharyngeal slits, endostyle, post anal tail
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nerve tubed formed by what?
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infolding of the neural plate = why it's hollow too
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what do adult ascidaceans still have of the 5?
2 other things |
endostyle (for food catching mucous), pharyngeal slits - to filter food,
heartbeat reversal and high levels of weird metals. hermaphroditic |
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sub P cephalochordata
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lancelets!
bottom dwelling filter feeder, sexes separate from here on (?) Planktotrophic larvae |
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ammocete
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larvae of lampreys
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Class Myxini - hagfishes, 4 things
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no paired appendages, no jaws, naked skin, fibrous cartilage skeleton, differentiated brain, iso osmotic, slime as defence
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Class Chondrichtyes
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sharks skates and rays - cartilaginous fishes, polyphondant teeth = constantly replenishing, Placoid scales
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Class actinoptergii
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ray finned fishes
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class sarcoptergyii
2 eg |
lobe-finned fishes
lungfishes, coelacanths |
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Class Amphibia - order gymnophonia
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caecilians - limbless, internal fert, tail short or absent (as op to legless lizzards with long p anal tail)
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order Anura - something unique
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only amphibian with exernal fertilisation, lateral line replaced by ear, colour vision,
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disadvantage of amniotic egg
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needs internal fert
can't be laid in water or the baby will drown |
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scales of reptile cf scales of a fish
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reptile scales are keratinised, epidermal (fish = bony, dermal)
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order testudines
2 things |
turtles, jaws with keratinised beaks, secondarily anapsid
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reproduction in birds
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left ovary only, testes cyclic
precocial young = mature when hatched |
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skeletal adaptations for flight
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fused clavicula, keeled sternum for muscle attachment (keeps centre of gravity low), fused fingers in wings, fused ankle bone
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feathers are homologus to____
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reptile scale
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heterodont teeth
diphodont |
more than one kind eg molars, incisors
have baby teeth and adult teeth |
