Ch. 33 pt 1 Flashcards
What are invertebrates?
animals that lack backbone
what are the 4 feeding strategies?
1) filter feeder
2) mass feeder
3) deposit feeder
4) fluid feeder
map sponges from kindom Animalia
subkingdom: Parazoa
phylum: Porifera
Phylum Porifera characteristics (6)
1) Porifera (pore bearer)
2) Sponges
3) Lack tissues
4) Multicellular with several types of cells
5) No apparent symmetry
6) Adults are sessile, larvae are free-swimming
what type of feeding strategy do sponges use?
filter feeding
What is filter feeding?
Capturing food particles suspended in the water that pass through their body
Explain water movement for sponges
Water is drawn through pores into a cavity called the spongocoel and out through an opening called the osculum
What is an ostium?
an opening into a vessel or body cavity
what is an osculum?
Main opening at the aboral end of sponges
what are porocytes
cells that create the opening in sponges
osculum (Latin origin)
mouth
What are the 2 different cell types in sponges?
1) choanocytes
2) amoebocytes
What separates the 2 cell layers in sponges?
gelatinous noncellular mesohyl layer
Characteristics of choanocytes (3)
1) flagellated collar cells
2) generate water current through sponge
3) ingest suspended food
characteristics of amoebocytes (5)
1) totipotent
2) found in mesohyl
3) play a role in digestion and manufacturing of skeletal fibers
4) absorb, digest, and carry food from choanocytes
5) move by pseudopodia
choano
funnel
What is the function of spicules?
structural support; mesohyle
Explain sexual reproduction for sponges? (4)
1) most hermaphrodites produce egg and sperm
2) gametes from amoebocytes or choanocytes
3) fertilization occurs in mesohyl
4) larvae exit through the osculum
Explain asexual reproduction for sponges?
via fragmentation
small fragment or bud detach and form new sponge
what is sequential hermaphroditism?
function as one sex and then as the other
Characteristics of Phylum Cnidaria (5)
1) radial symmetry
2) Diploblastic
3) gastrovascular cavity
4) single opening
5) true nerve cells arranged in nerve net
What are the two types of body plans in Cnidaria?
1) sessile polyp
2) motile medusa
What is a gastrovascular cavity?
extracellular digestion or incomplete gut
acts as hydrostatic skeleton in cnidarians
sessile
stuck to one place; attached to a substrate
polyp
a small growth with stalk
motile
moving or movable
How do cnidarians feed?
1) carnivores that use tentacles to capture prey
2) contain nemotocysts
cnidocil
hair-like trigger
what are cnidocytes?
contain trigger (cnidocil) and nematocyst that sting
what controls movements in a cnidarian?
noncentralized nerve net
hydro
water
scyph
cup or can
Anth
flower
What are the 4 classes of Phylum Cnidaria?
1) hydrozoa (ex. hydra, and obelia)
2) scyphozoa (ex. jelly fish)
3) anthozoa (ex. sea anemone, and coral)
4) cubazoa (ex. box jellies)
Characteristics of Ctenophora (comb jellies) (5)
1) 2 long tentacles without stinging cells that contain colloblasts
2) complete gut
3) calcareous particles
4) hermaphrodite
5) bioluminescent
Act as orientation cue in Ctenophora
calcareous particles
Collo
glue
cteno
comb
Characteristics of Class Cubazoa
1) have image-forming eyes (true organs)
ex) box jellies
What are the characteristics Phylum Platyhelminthes? (9)
1) Flatworms
2) Respire by diffusion: lack a specialized respiratory or circulatory system
3) distinct excretory system with protonephridia and flame cell
4) More centralized nervous system
5) Acoelomates (without body cavity)
6) bilaterally symmetrical with a head
7) Cerebral ganglia receive input
8) light-sensitive eyespots or ocelli
9) Sexual and asexual reproduction
Platy
flat
helminth
parasitic worm
What are ocelli?
simple eye, eye spot
a
without or non
coel
body cavity
Nephridia
Nephrons-Kidneys
Planarians (3)
1) Live in fresh water and prey on small animals
2) Has ocelli and centralized nerve nets
3) Hermaphrodites and can reproduce sexually or asexually through fission
Trematoda (3)
1) Are parasites
2) Parasitizes humans spend part of lives in snail hosts
3) Produce surface proteins that mimic their host and release molecules that manipulate that host’s immune system
Class Cestoda (6)
1) Tapeworms and parasites
2) head is called scolex in which there are several suckers
3) attach to intestinal walls of the host
4) absorb food that the host has digested
5) doesn’t kill host but causes to loose weight
6) Divided into sections called proglottids
Class Cestoda reproduction (3)
1) contain little more than male and female reproductive organs
2) Sperm fertilize the eggs within the proglottids
3) Fertilized eggs are released when mature proglottids break off and burst off and open
Phylum Nemertea (3)
1) Mainly marine but a few inhabit fresh water
2) simple circulatory system (no heart)
3) complete digestive tract (separate anus and mouth)
ex) Proboscis worms
Phylum Rotifera (5)
1) tiny
2) marine
3) multicellular and have specialized organ systems
4) Complete digestive tract (alimentary canal)
5) Parthenogenesis unfertilized diploid eggs develop into females unfertilized haploid eggs become degenerate males that live long enough to produce sperm
What is parthenogenesis?
when unfertilized diploid eggs develop into females
Phylum Nematoda (2)
1) Have an alimentary canal
2) Lack circulatory system
Trichinella spiralis
Is a parasite that can be acquired by humans from undercooked pork
what is an alimentary canal?
digestive tube with separate mouth and anus
