Flashcards
Invertebrates
Cards in this deck (57)
- 1Helminthologythe study of flukes, tapeworms and roundworms
- 2What must parasites do?- reproduce within the definitive host
- get fertilised eggs or embryos out of host
- recognise and contact a new approprite host
- get into new host
-find the right location in host & stay put
- withstand anaerobic environment
- avoid host digestive and immune sustem
- avoid killing host - 3Bizarre papsitestongue eating louse
botfly
toothpick/vampire fish
cordiceps - 4altering behaviour of hostflukes cause snail hosts to seek light so they are more likely to be eaten by birds
others cause eyestalks to resemble caterpillars
some stop sexual repro- nemadode infection in Potamopyrgus, heavy load+sexual, light load=asexual - 5Phylum Platyhelminthesflatworms simplest lophotrochozoans- no enclosed body cavity
lack organs for transporting oxygen
simple organs for excretion
flattened so all cells near a surface
move by beating bands of cilia
digestive tract is a mouth opening to a blind sac- highly branched for ^ surface area
eat living or dead animal tissue. release digestive juices then suck up partially digested food - 6Mariine Turbellariaswim in rthymic contractions of body muscle
creates a series of undulating waves propelling them over ground
small flatworms glide on surface cilia - 7Life cycle of Digenean5 stages: miracidium. sprocyst, redia, cercaria, metaceraria
2 or more intermediary hosts- 1st mollusc
specificity towards molluscan host
asexual repro im intermediary hosts
sexual repro only in vertebrate definitive host - 8class cercomeromorpha: subclass monogeneaone host
larav becomes attached to tadpoles that hatch out from eggs
as tadpole metamorphoses into a frog the parasitre migrates to the host bladder
parasite takes 3 years to become adult
sex hormone of host induce egg production by parasite - 9subclass cestodatapeworms
non-ciliated tegument covers cestodes
tegument has no cell membrane
no digestive tract
aquired nutrients through highly folded outer surface
scolex buds proglottids, each is hermaphrodite and may contain 50,000 eggs, proglottids shed with faeces - 10superphylum ecdysozoaexoskeleton shed, then they expand and harden a new one
- 11Phylum nematoda (roundworms)cylindrical psudocpelomates with tapered ends and a thick cuticle
longitudonal muscle only
complete gut
sexes separate
exchange oxygen and nutrientstheor their cuticle and intestine
plant ana animal parasites - 12Mollusca: Gastropodahead
terrestrial
motile, foot for crawling, burriwong ect
conversion of shel for deep protective retreat
torsion- twisting of body 180 anticlockwise, gills, anus, head behind the head, allow withdrawel of head before foot, independant of shee spiralling - 13opithbrachsshell and mantle cavity reduced or absent
many bilaterally symmetrical
sea hares, sea butterflies, sea slugs - 14class cephalopodahead has prehensile tentacles,
jet propulson
carnivorous
majority 6-70cm
ink gland
colour change
complex nervous system and behaviour highly developed eyes
vascular system
internal fertilisation
respiratory pigment hhemocyanin- 25% as efficient as hemoglobin
nerves unmyelinated
deaf as adaptation to predation by whales/dolphins that stun prey woth sound - 15squidshell reduced to pen made of chitin
male places spermatophore within female mantle using copulatory appendage - 16chromatophoresmuscle under nervous control
several layers of coloured cells
underneath are reflective cells that refract and reflect light - 17Generalised molluscbilateral symmetry
poorly cephalised
aquatic
moves and grazes over a hard surface
radula- used in feeding - 18layers of mollusc shella: periostracum
b:ostracum
b1: prism layer
b2:plate layer
c: hypostacum or nacre - 19class Aplacophoraworm like
primitive- poorly cephalised head, covered by a cutlicle with calcareous scales
specialised- reduction of foot, loss of radula and loss of gills - 20Polyplacophoraadapted to adhere to rocks
no cephalic eyes or tentacles, head indistict
multiple gills
segmented shells- 8 overlapping plates - 21Monoplacophorageneralised and ancestral
- 22Bivaliaclams, oysters, mussels
laterally compressed
shell of 2 hinged halves
filter feeders
water come in through siphon and foos is extracted using gills
poorly cephalised - 23Mussel glue protein5 proteins with a high conc of DOPA
- 24scaphopodatusk or tooth shelled
elongated cylindrical tube, open at both ends
burrowing marie mollusks - 25Phylum Annelidasegmented worms
body wall with outer circular and inner longitudinal muscle layers
outer transparent moist cuticle secreted by epithilium
chitinous setae- oten on appendages called parapodia
coelom well developed and divided by septa
coelmic fluid supplies turgidity & hydrostaatic function
blood system closed and segmentally arranged
gas exchange through skin, gills or parapodia
expiratory system a pair of nepheridia
nervous system with a double ventral nerve cord and pair of ganglia
brain a pair of dorsal cerebral ganglia
sensile system
hermaphrodite or separate sexes - 26class polychaetawell differnciated head
specialised sense organs
paired appendages on most segments
sexes separate
life habits- free moving (errant), sedentary burrowers, or sedentary tube formers (filter feederd or endosymbiotic bacteria) - 27tube living, deposit feeding annelidsinjest upto 120x own weight
5% of sediment dry weight is organic matter - 28tube living, filter feeding annelidstentacles have respiratory and feeding functiions
tiny food particles passed into muscus band back to mouth
light sensers on tentacles detect shadows- pull into tube when threatened - 29oligochaetabear setea
hermaphrodites
predators, detritivores and direct deposit feeders - 30Hirundinaeleeches
fixed number of segments- 34
antirior and postirior suckers
no septa or setae
lack parapodia and tentacles
coelom filleed with mesenchyme
earthworm like peristalsis
medical uses- black eyes, arthritis, reattachment of skin flaps
blood does not coagulate but continues to flow- calin inhibits platelet adhesion and decorsin inhibits platelet aggregation, hirudin inhibits activation of prothrombin - 31digesstion in leechesonly exopeptidases
digestion slow- 200 days to digest 2-3x its body weight in blood
no food for upto 18 moths
gut bacteria may contribute to digestion - 32leech salivaa vasodilator- dilates bolld vessels to encourage flow
an anaesthtis- reduce the liklihood of the host feeling their presence
an antibiotic- produced by symbiont bacteria - 33what are lophophoratesprotostomes (shown by DNA)
lophophore is a crown of ciliated tentacles used for feeding
lophophorates are sessile suspension feeders enclosed in a exoskeleton - 34Bryozoa or moss animals (Ectoprocta)colonial, individual zooids secrete a house and multiply asexually
members connected by funicular cords- nutrients exchanged
zooids <1mm
upto 2mill in a colony
marine
U shaped gut
can move their lophophores - 35Kleibers lawas animals grow, the metabolic rate per unit weight of tissue declines so biomass accumulates as a slower rate as an individual grows
colonies- no reduction in metabolic rate, or rate of growth as colony becomes bigger - 36Advantages of colony- growth accelerates not decreases with colony size
feeding, non-diving zooids in the centre contribute nutrients to the active ones at the periphery - 37Echinodermataspiny skin
radially symmetrical
calcarous exoskeleton
larvae bilaterraly symmetrical
oral and aboral surfaces
deutrostomous
gut complete
no excretory or gas exchange organs
nervous system decentralised
ciirculatory system comprises a haemal system derived from coelomic cavities and sinuses
complex system of fluid filled canals derived from coelom (water vascular system) servicing tube feet
mostly dioecious - 38mutable connective tissuerapid and reversab;e change in stiffness- under nervous control
change in viscosity of collagen fibres
ionic movement alter weak interaction between macromolecules
muscle tone altered without energy involved with muscular contraction - 39crinoideasea lilies and feather stars
suspension feeders - 40Asteroideasea stars
scavengers and predators - 41Ophiuroideabrittle stars and basket stars
predation, deposit feeders, scavenging and suspension feeders - 42Echinodeasand dollars and sea urchins
herbivory, suspension feeding, detrivory, predation - 43Holothuroideasea cucumbers
suspensiion or deposit feeders - 44sea urchinmodels
live >100 years
23,300 genes with representatives in all vertebrae families
sophisticated immune system more complex than vertebrates
orthologs of genes associated with visio, hearing, balance ect - 45Phylum Onychophoramissing link between annelids and arthropods
moulting chitinous cuticle
soft, fleshy non-jointed appendages, nephridia - 46Phylum tradigrada- water bearsanabiotic
can freeze or dry
x-rays of 570,000 rads
vacuum or high pressure
found everywhere - 47common Arthropod featuresexoskeleton
moulting in order to grow
jointed limbs
dorsal heart
well developed head - 48Why are arthropods so successful?hard exoskeleton and ecdysis
many limbs
tagmosis
many modifications of the limbs
complex seense oragans
small (<25mm) - 49class Myriapodacentipedes and millipedes
many legs
2 tagmata: head and trunk
antennae, mandibles and 2 pairs of maxillipeds
terrestrial
system off tubes for gas diffusion - 50Subphylum Chiliceratainvaded land
maine and terrestrial
2 tagmata: prosoma and opisthosoma
bears chelicerae, pedipalps and 4 pairs of walking legs - 51crustaceadominant marine arthropods
2 pairs of antennae
jaw like mandibles
2 pairs of maxillae
additional feeding appendages - 52Crustacea major groupsbrachiopoda- water fleas, shrimp
maxillopoda- copepods, barnacles, ostracos, mystacocarids
malacostraca- shrimps, lobsters, craps, krill, woodlice, sandhoppers - 53Subphylum hexapodaprimarily terrestrial
head, thorax and abdomen, antennae, mandiples and 2 pairs of maxillae
3 pairs of walking legs
tracheal system for gas exchange - 54class insectaapterygotes- wingless primitive insects
pterygotes- winged insects
gradual changes between stages- memamorphis incomplete
dramatic changes- compelet metamorphis - 55Why are insects successful?small size
highly organised sensory system and complex neuromucculature
toug waterproof exoskeleton
tough resistant eggshell
wings - 56insects are smallhelps parasitic insects avoid attention of host
can use small living spaces
unavailable to larger animals - 57why no large insectsrespiratory system
weight problem at ecdysis
vulnerable to predators- heating up time, time to maturity
beetles- bigger ones have greater fraction of body trachea, opening into leg is a bottleneck, space available for trachea in the leg limits size
partial pressure of oxygen limiting (20.9 kPa)
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- Flashcards on Invertebrates , created by Georgie Halford on 17/05/2015.
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