Invertebrates Part 1 Flashcards
What phylum is part of the clade Parazoa?
Porifera
What animal is part of phylum Porifera?
sponges
Where are sponges a found?
marine and freshwater
How are sponges in the larval stage compared to the adult?
larval are free swimming while adult are anchored onto a submerged object (sessile)
What characterizes the clade Parazoa?
no body symmetry and no tissues (have cells though)
What does sessile mean?
anchored
What symmetry do sponges have?
asymmetrical
What shapes do adult sponges have?
vase shaped
Are sponges simple or complex?
very simple
What are the layers of the sponge body wall?
inner, middle, and outer
What are the body walls of sponges made of?
layers of cells that lack discrete (?) organization
Describe the inner layer of a sponge’s body wall
specialized cells called choanocytes, or collar cells
Describe the middle layer of a sponge’s body wall
- gelatinous, protein-rich matrix mesohyl
- may contain spicules and/or spongin
What are spicules? Is it hard or soft?
skeletal spikes of silica or calcium carbonate, rigid or hard
What is spongin? Is it hard or soft?
protein fiber, soft
Describe the outer layer of a sponge’s body wall
protective “epithelial” cells
Do sponges have a epithelium?
no, the “epithelial” cells are simply a descriptive term
What layers of the sponge’s body wall are unique to sponges?
inner and middle
Do sponges contain both spicules and spongin?
some are exclusively spongin and some contain both
How do sponges eat?
filter feeders
How does filter feeding work?
move water from outside of the animal through pores where food can be filtered. Water moves from outer area through little channels into the inner space which opens to the outside on the top
What are the three body plans?
asconoid, synconoid, and leuconoid
What is asconoid?
simplest
What is synconoid?
increased surface area
What is leuconoid?
greatest surface area
What helps sponges feed?
choanocyte flagella
How do sponges reproduce?
asexually and sexually
How do sponges asexually reproduce?
fragmentation, gemmule formation
How do sponges sexually reproduce?
egg and sperm spawning
What is fragmentation?
body breaks down
How do larval sponges swim?
use cilia
What do larval sponges do before they can become adults?
settle down on a substrate
Do sponges produce both sperm and egg?
yes some do, but they cannot fertilize their own
What clades are part of Eumetazoa?
radiata and bilateria
What are radiata?
have radial symmetry
What are bilateria?
have bilateral symmetry
What phylums are part of radiata?
Cnidaria and Ctenophora
What animal are Ctenophora?
comb jellies
What phylums make up Bilateria?
all other animals besides Cnidaria and Ctenophora
Where do Cnidarians live?
nearly all marine
Describe Cnidarian’s body systems?
distinct tissues but no organs
Are Cnidarians triploblastic or diploblastic?
diploblastic
What does diploblastic mean?
2 germ layers
What layers do diploblasts have?
- ectoderm (epidermis)
- endoderm (gastrodermis)
- mesoglea (non living layer)
What is the mesoglea?
a layer of gelatinous material
What type of eaters are Cniderians?
carnivores
What two body forms do Cnidarians have?
polyps and medusae
What shape do polyps have?
cylindrical
Do polyps move?
no, they are sessile
Do medusae move?
yes they are free living
What shape do medusae have?
umbrella
Are more Cnidaria polyps or medusae?
some are either medusae or polyps, others alternate
How do polyps reproduce?
sexually or asexually; use budding
What is the gastrovascular cavity?
it acts as a gut, it is not a body cavity
If something has a gastrovascular cavity, then it is?
acoelomate
What is budding?
growing a new polyp out of its side; may produce a new polyp or medusae
How do medusae reproduce?
sexually; external fertilization
What are medusae larva called?
planulae
Are medusae larvae free swimming or sessile?
free swimming
How do Cnidaria digest?
internal extracellular digestion
- extracellular fragmentation in the gastrovascular cavity
- phagocytosis and intracellular digestion
What happens in the gastrovascular cavity?
enzymes released into the cavity
How does intracellular digestion work?
further break down inside cell
what systems do Cnidaria lack?
circulatory, respiratory, and excretory
What is the respiratory system?
lungs, gills
What is the excretory system?
removes waste
How does internal extracellular digestion work?
break down prey into components (macromolecules)
How do Cnidaria get nutrients?
move nutrients through the tissues by diffusion
How do Cnidaria get rid of waste?
oxygen gets diffused into the body, and CO2 and other waste gets diffused out
What unique cells do Cnidaria have on their epidermis?
cnidocytes
What is a special type of cnidocyte?
nematocyst
What is a nematocyst?
a stinging cell that produces a toxin, it has a small but powerful harpoon
What is the function of nematocysts?
food acquisition and defense
Where are nematocysts mainly located?
tentacles
If Cnidarias can’t see, how do they know when to release the harpoon from nematocysts?
they can sense what has bumped into them and that triggers the release
What are the four classes of Cnidarians?
Hydrozoa, Cubozoa, Syphozoa, Anthozoa
What animal are Hydrozoa?
hydroids
What animal are Scyphozoa?
jellyfish
What animal are Cubozoa?
box jellyfish
What animal are anthozoa?
sea pens, sea pansies, corals, and sea anemones
Do true jellyfish or cube jellyfish have more toxic venom?
cube
Where do Hydrozoa live?
the only fresh water and marine
What form are Hydrozoa in?
polyp and medusae
What is obelia?
a polyp genius of hydrozoa
How do Hydrozoa feed?
they paralyze prey and bring towards mouth
Do Hydrozoa stay fixed?
no, they can tumble from place to place and have a stick pad to anchor
What Cnidarian class is the Portuguese Man O’ War?
Hydrozoa, it is a colony of polyps and some perform the special function of creating a sail which is filled with gas
What form are Scyphozoa in?
most commonly in medusae
Where are Scyphozoa found?
marine only (not exactly true b/c there is a freshwater species)
What is a genus of Hydrozoa?
obelia
What is a genus of Scyphozoa?
Aurelia
What defense do Scyphozoa have?
can inflict painful stings
Do Scyphozoa live in cold or warm water?
both
Are Scyphozoa important for the food chain?
yes, sea turtles eat jellyfish
How do Scyphozoa move?
muscle tissues naturally contract, so they pulse because of contracting their muscle cells
What are Anthozoa important for?
marine reef ecosystems
What form are Anthozoa in?
polyp
How do Anthozoa live?
colonial and solitary
What do corals secrete?
calcium carbonate
Why do corals secrete calcium carbonate?
to build the reef, protection
What type of relationship do corals have with other organisms? How?
symbiotic; Organism live inside and provides nutrients while coral provides protection (??)
Are corals colony or solitary?
colony
Are sea anemones colony or solitary?
solitary
How do sea anemones stick to surface?
have an adhering disk
How do sea anemones have a relationship with clown fish?
clown fish are adapted to live amongst sea anemones by secreting a mucus that protects them from being stung
What form are Cubozoa in?
mostly medusae
Are Cubozoa dangerous to humans?
sting can be fatal
Are Cubozoa advanced or simple?
some species have advanced sensory structures
Can Cubozoa see?
no; some species have eyespots that allow them to distinguish from light and dark
What phylum are flatworms? What clade?
Platyhelminthes; bilateria
What are the two major groups of Platyhelminthes?
free-living flatworms and parasitic flatworms
What class are free-living flatworms?
Turbellaria
What two classes make up parasitic flatworms?
Trematoda and Cestoda
Where do Parasitic flatworms get nutrients?
from body of host
What kind of digestive tract to Platyhelminthes have?
incomplete or none at all
Do Platyhelminthes have an excretory system?
yes
Do Platyhelminthes have a nervous system?
yes but it is primitive, however it is more developed in the free-living
How do Platyhelminthes move?
ciliated epithelia cells, musculature
What is a problem Platyhelminthes can face? Why? How fix?
excess water entering the body due to osmosis because of how flat they are; get rid of excess water
What is the digestive tract for Turbellaria?
incomplete digestive cavity with only one opening (mouth but no anus) - so what goes in the mouth must leave by mouth
What is the digestive tract for tapeworms and flukes?
lack digestive systems
How do tapeworms and flukes get nutrients?
absorb food directly through body walls
Which is more harmful, tapeworms or flukes?
flukes because they can block the flow of bile in the liver
What excretory system do Turbellaria have? What does it consist of?
excretory and osmoregulatory; network of fine tubules and flame cells
Where are flame cells located?
the side branches
What is the primary function of flame cells?
water balance
What is the secondary function of flame cells?
excretion
How are metabolic wastes excreted for Turbellaria?
excreted into the gut and eliminated through the mouth
What is the function of the fine tubules in Turbellaria?
collection of water
What is the osmoregulatory system in Turbellaria?
similar to our kidneys, removes excess water
Do Turbellaria have a circulatory system?
no because there body is so flat that diffusion takes care of gasses and nutrients into tissues
Can Turbellaria see?
they can have simple eyespots but cannot see, they can distinguish light from dark
What is the advantage of eyespots for Turbellaria?
so they can know if they are covered or sheltered
How do Turbellaria reproduce?
sexual reproduction, and can also do asexual regeneration
How do Turbellaria reproduce sexually?
most are hemaphroditic, get in close contact with others
What predators do Turbellaria have?
fish, salamanders, frogs
What serves as a “brain” in Turbellaria?
anterior-cerebral ganglion
What is the anterior-cerebral ganglion?
conglomeration of nerve cells, serves as a very primitive brain. The eyespots are on top on it
Where are free-living flatworms found?
freshwater, marine, and terrestrial environments
What are the projections on free-living flatworms’ head?
touch receptors
What class are flukes?
Trematoda
What do flukes live as?
ectoparasites or endoparasites in the bodies of other animals
What is an ectoparasite?
external attachment (aquatic only)
What is an endoparasite?
inside body
How do flukes attach?
suckers, anchors, or hooks
How many hosts do flukes have in their lifecycle?
involves one or two hosts (larval into juvenile stage in one and adult in another)
What are the two types of parasitic lifestyles?
Direct and indirect
What is a direct parasitic lifestyle?
only always one host
What is an indirect parasitic lifestyle?
two or more hosts
What are the three types of parasitic hosts?
definitive, intermediate, and paratenic
What parasite stage lives in a definitive host?
adult parasite (where sexual reproduction occurs)
What parasite stage lives in an intermediate host?
larval form (asexual reproduction??)
What parasitic stage lives in a paratenic host?
host serves as transport
What happens if you break the parasitic lifecycle chain?
can not complete lifecycle
What can break the parasitic lifecycle?
- create sanitation system
- get rid of snails (intermediate host)
- cook meat thoroughly
What is the definitive host for flukes?
humans
What is the intermediate host for flukes?
snails
What is the paratenic host for flukes?
fish
Every vertebrate has its own ___________.
tapeworm species
What class are tapeworms?
cestoda
What do tapeworms do?
live as parasites within the bodies of other animals
Where do tapeworms most often occur?
in the intestines of vertebrates
Do tapeworms have eyespots?
no
Do flukes have eyespots?
no
How is the body of Cestoda devided?
scolex, neck, and proglottids
What is the scolex?
attachment organ
What is the neck?
unsegmented portion
What is the proglottids?
repetitive sections, each with a complex hermaphroditic unit
What is the beef tapeworm?
Taenia saginata
What segment is most of the Cestoda body?
proglottids
How do Cestoda spread?
break off parts of proglottids and pass through fecal
How do dogs get tapeworms?
flea eats proglottids and then flea carries the tapeworm and then a dog gets fleas and eats a flea and get tapeworm
What clades are Platyhelminthes part of?
bilateria acoelomates
Where are Cycliophora found? And what clade?
exclusively on mouthparts of clawed lobsters, bilateria acoelomates
What do pseudocoelomates possess?
a pseudocoel
What is a pseudocoel?
a cavity between the mesoderm and endoderm
What does a pseudocoel serve as?
a hydrostatic skeleton, against which the animal’s muscles can work
What do pseudocoelomates lack?
a circulatory system
What do pseudocoelomates use in place of a circulatory system?
fluids that move within the pseudocoel
How does the pseudocoel act as a circulatory system for pseudocoelomates?
fluid is inside the cavity and when the muscles contract it pushes the fluid. It allows the animal to have a more rigid body than a soft animal and aids in movement. When the fluid moves around, it brings in oxygen
What phylums are under Pseudocoelomates?
Nematoda and Rotifera
What animal are nematodes?
roundworms
What types of nematodes are there?
free living and parsitic
Where do free living nematodes live?
marine, freshwater, and soil
Where do parasitic nematodes live?
inside host (animal and plant (?))
What type of symmetry do nematodes have?
bilateral
Are nematodes segmented or unsegmented?
unsegmented
What body shape do nematodes have?
cylindrical
Do nematodes have a complete digestive tract?
yes
What are nematodes covered in?
a flexible, thick cuticle
What is the function of the cuticle?
protect the animal’s body, slows down loss of water and osmosis of water, protects body when moving through soil
What must a nematode do in order to grow?
molt their cuticle, around 4 times during larval stage (?)
What do nematodes exchange through their cuticles?
oxygen
What are nematode mouths equipped with?
piercing organs called stylets (analogous to teeth)
How do nematodes eliminate waste?
through the anus
How do nematodes eat?
food passes through the mouth by the sucking action of the pharynx
Are nematodes bad or good?
some are beneficial and some damaging
How nematodes reproduce?
sexually
Are nematodes hermaphrodites?
no, the sexes are separate
How do nematodes have offspring?
most eggs, some live birth
What is it called when the sexes are separate?
dioecious
How are nematodes efficient?
males have elaborate organs because insertion instead of leaving in environment
How many eggs a day can a female nematode lay?
up to 10,000
What can nematodes cause in humans?
diseases
What diseases can nematodes cause?
trichinosis, intestinal roundworm, and elephantiasis
What causes trichinosis?
Trichinella
What causes intestinal roundworm?
Ascaris lumnricoides
What results from trichinosis?
cysts in the muscles
What diseases can nematodes cause in animals?
heartworm
What is elephantiasis?
a type of nematode passed by fly bite gets into animal which then defecates on sand. When walking on sand barefoot, worms get under skin and into the lymphatic system causing a blockage which results in edema
What is heartworm?
transmitted by mosquitos, worms go into the blood stream and to the heart
What type of body symmetry to Rotifera have?
bilateral
Are Rotifers segmented?
unsegmented
What kind of organs do Rotifers have?
complex internal organs
Do Rotifers have a complete digestive tract?
yes
What nickname do Rotifers have?
“wheel animal”
Why are Rotifers nicknamed “wheel animal”?
because of their wheel-like mouth arrangement
Where are Rotifers found?
aquatic - freshwater
How big are rotifers?
microscopic
How are Rotifers complex?
have something similar to a heart
Are Rotifers hermaphroditic or doecious?
some are hermaphroditic and some are doecious
What is the mouth part of Rotifers called?
corona
What is the function of the foot of the Rotifer?
allows it to hold onto something like a twig
Do Rotifers have eyespots?
some do to distinguish between light and dark
Are Nematodes or Rotifers more advanced?
nematodes
What is the function of the corona in Rotifers?
to swim around and eat
How do Rotifers eat?
have cilia that pull food particles into the animals mouth
Do Rotifers have a nerve cord?
yes
What shaped stylets do Nematodes have?
pointed ones in parasites and flatter ones in free living
What kind of eaters are parasitic nematodes?
blood suckers
