Test 2 Flashcards
how are animals defined?
multicellular
heterotrophic
diploid
reproduce by oogamy
five key transitions of animal evolution
tissues
symmetry
body cavities
developmental patterns
segmentation
parazoa definition
lack defined tissues and organs
can aggregate / disaggregate
eumetazoa definition
distinct well-defined tissues
irreversible differentiation of cells
two distinct layers (ecto/endo)
tissue types of eumetazoan organisms
muscular
connective
neural
adipose
bone
blood
cephalization definition
area in which neural ganglion form
typically near other sensory organs
3 germ layers
endoderm
mesoderm
ectoderm
what is a coelom?
a body cavity lined with mesoderm
what is an acoelom?
organism with no body cavities that is solid throughout
what is a pseudocoelom?
animal with a false coelom
characteristics of a protosome
spiral cell growth
blastophore becomes mouth
characteristics of deuterostomes
radial cell growth
blastophore becomes anus
K selection
producing few offspring and devoting a greater amount of resources to it.
ex - humans
r selection
producing many offspring and devoting fewer resources to their development.
ex - mosquitos
what is the earliest, most simple animal known?
trichoplax adaherens
Characteristics of porifera
no tissues, organs, or symmetry
hermaphroditic
example of porifera
sponges
skeleton of sponges are typically composed of
silica
calcium carbonate
protein (spongin)
what does a collar cell do?
brings water through pores of sponge by waiving flagella
what is the opening of the sponge called?
oscula
what is a chanocyte?
an example of a collar cell amongst the interior of a sponge that assists in propulsion
examples of organisms in Cnidaria
hydra
jellyfish
coral
sea anemones
Body forms of Cnidaria
polyp
medusa
what is a polyp?
a cylindrical organism that attaches to a substrate
what is a medusa?
free floating umbrella shaped organism
what is a cnidocyte?
cells on tentacles that initiate nematocysts to paralyze prey
what phylum are the class of hydrazoa in?
cnidarians
what makes the hydrazoa special?
have both polyp and medusa stages in their life cycle
marine
colonial
What phylum are the schyphozoa in? What makes them special? what is an example?
cnidaria
medusa stage is dominant (bell-shaped)
diecious
planulae (larval stages that form into polyps)
what are the cubozoa? what makes them special?
a class of box jellyfish in the cnidaria phylum
change from radial symmetry to bilateral
tentacles at the corner of each box
very predatory, increased sensory system
class example of a cubazoa?
sea wasp or irujandji
very small but very dangerous
what are anthozoa? why are they important? what phylum?
sea anemones and coral
solitary / colonial animals
planulae stage that forms polyps instead of medusa
Phylum Ctenophora?
comb jellies
modified bilateral symmetry
more complex nervous system
bioluminescent
two major groups of platyhelminthes?
free-living worms (turbellaria)
parasitic flatworms
what are the types of parasitic flatworms
trematodes - flukes
cestoda - tapeworms
what do flame cells do?
function in balancing water levels and excretion
what are turbellaria?
class of platyhelminthes
free-living flatworms
what are monogenea and trematoda?
flukes
monogenea - endo-parasites
trematoda - ectoparasites
what is a schistosome?
Where are they common?
a fluke that diecious with sexual repro
Lake Victoria
where are schistosomes prevalent?
what saves an infected person?
lake victoria
PZQ
What is a cestode?
class of platyhelminthes
tapeworm
what are the three regions of a cestode body?
scolex - attachment organ
neck - unsegmented portion
proglottid - repetitive hermaphroditic units
what are the pseudocoelomates?
nematodes
rotifers
what is a pseudocoel? what is its purpose?
cavity between meso and endoderm
hydrostatic skeleton that changes pressure to allow organism to move
nematode characteristics
bilateral symmetry
unsegmented
pseudocoelomate
complete digestive tract
many are parasitic
sexual reproduction
diecious & dimorphic
anus
importance of flat vs roundworms
flat - SA to Vol ratio is high, organism can digest and excrete through its skin
round - complete digestive tract, more efficient
composition of nematode
digestive and reproductive tract
what is a cuticle?
almost like an exoskeleton that surrounds roundworms to prevent drying out
molted and shed to allow for growth
what is a stylet?
a puncturing device that nematodes use to penetrate its food source
what is the importance of the pharynx in nematodes?
an organ structure that vacuums food from outside to inside
what is the importance dracunculus medinesis
modern medical symbol (snake on cross) that was developed from pulling worms out of the body
what is a corona
flagellated cells that spin and sweep food into the gut
importance of rotifer phylum
greater complexity for their size
specialization of body regions
advanced neural system
complete digestive tract
what does a ceolom allow for
body fluid repositioning
complex and larger tissues to develop
larger body size
examples of mollusks
snails, slugs, clams, octopus
what is a chiton?
primitive mollusk
what determines the color of a pearl
color of water
what is a visceral mass
where the digestive, excretory, and reproductive organs are concentrated
what is the mantle?
thick epidermis that covers the dorsal side of the body
forms a cavity that the visceral mass takes up
what is the muscular foot ?
adaptation for locomotion, attachment, and / or food capture
what is a radula?
file like strucutre that is used to scoop things from ground
first evidence of teeth like structures
what are different about a snail’s gills
they are terrestrial, but surrounded by mucosal fluid
what are nephridia?
special excretory structures that remove nitrogenous bases from processing protein
how do cephalopods’ circulatory and nervous systems differ from other mollusks?
closed circulatory system
advance nervous / sensory systems
what is the process of torsion?
when the mantle cavity moves from the posterior to anterior resulting in a twist of the gut
how do crustaceans and bivalves differ?
crustaceans adopt shells whereas bivalves produce their own shell
what is a siphon in a bivalve?
the tube that water is filtered through in a bivalve
how many arms/tentacles do squids, octopus, and nautilus have?
10
8
80-90
what is a chromatophore?
a cell that uses pigment to shift light in order to change color in moments of camouflage
what is the biggest evolutionary step that can be witnessed in the annelids?
segmentation
importance of segmentation?
fusion of segments that allows for cavity specialization
nerve cord can run through and connect each segment with the brain
what are septa
divisions between segments
what are setae
barbs that allow organisms to move through the environment by anchoring and pulling forward
what are chaetae
chitin bristles that anchor the worms
two classes of the annelids and their characteristics
polychaeta - aquatic, feathery looking
oligochaeta - terrestrial, earth worms / leeches
what is a parapodia? what class of annelids are they associated with?
appendages that gather nutrients and food
polychaeta
what is the clitellum?
ring on the body of annelid that secretes mucus that holds worms together during mating
most dangerous animals on the planet
mosquito
tick
4 Classes of arthropods
chelicerate
crustacean
hexapods
myriapoda
what population of all species are arthropods?
two thirds
what evolutionary steps were established by the arthropods
segmentation
exoskeleton
joint appendages
what is tagmata
specialized segmentation (head, thorax, abdomen)
what is the importance of an exoskeleton
protects against water loss
must go through ecdysis for organism to grow
what is the exoskeleton made of
chitin - a glycoprotein
what is the importance of jointed appendages?
increased range of motion
organism can hold onto things
how does the circulatory system of arthropods differ?
muscles anchored to the exoskeleton that act as a secondary system when moved
what is a spiracle
opening along the body that allows for gaseous respiration
what are compound eyes? what are ommatidia?
independent visual units that attach to a common optic nerve to compile images that form vision
tracheae
passage into the body that’s branches go through all tissue
muscle contraction allows for branches to exchange gas
How is the body of a chelicerate designed? what are the characteristics of it?
2 tagmata
anterior (prosoma) have pedipalps and 4 pairs of walking legs
posterior contains reproductive organs
how is the crustacean body designed?
three tagmata with one being the cephalothorax
two pair of antenna
three pairs of appendages for chewing
How do crustaceans reproduce?
both internal and external fertilization
dioecious
what is the order name for barnacles
Cirripedia
hexapod body desingn
three tagmata
head
thorax with 3 segments, set of legs per segment
abdomen
what do a mosquito, butterfly, and fly’s head design tell us?
all have compound eyes and a feeding part
mosquito - piercing instrument to draw blood
butterfly - sucking instrument to get nectar
fly - sopping instrument
how is the gut designed in insects?
foregut, midgut, and hindgut
what does a tympanum do for insects?
it is a thin membrane that detects sound and vibrations
what is simple metamorphosis?
immature stages that are similar to adult, but are smaller
what is complete metamorphosis?
larva are not similar looking to adult
includes a resting stage where the organism molts
What are the two subclasses of myriapoda? what are examples of each?
chilopoda - centipedes
diplopoda - millipedes
how do chilopoda differ from diplopoda?
chilo - one pair of appendages per segments (carniverous)
diplo - two pair of appendage per segment (herbivore_
