BIO 202 Sponges and Cnidaria - Exam 3

the “colonial flagellate hypothesis” provides a theory for the origin of

origin of metazoa

for living cells, the advantage of oxidative (aerobic) metabolism over anaerobic metabolism is

it produces more than 10 times more energy for the same amount of food

which phyla are not “primitive” and have “super powers”

porifera (subkingdom parazoa); cnidaria and ctenophora (subkingdom radiata)

what are pores and canals in sponges used for

filter feeding

collar cells

choanocytes; specialized, flagellated cells lining the internal chambers of sponges

what do collar cells do

pump water for sponges and feeding; diffusion

skeleton of spicules

can be diverse, made out of silica or calcium carbonate; form the internal skeleton of most sponges

what have the superpowers allowed parazoa and radiate to maintain

allowed the to maintain their simple body plans

filter feeders

food is derived from suspended materials in water

why has sponge body plan evolves

to enhance filtration efficiency

archaeocytes

amoeboid cells that live in the mesohyl; are totipotent cells or stem cells

mesohyl

gelatinous extracellular matrix made of jelly-like collagen

what do the skeleton of sponges consist of

mixture of organic fibers and inorganic (mineral) components called spicules

collagen

major structural protein in metazoa (including sponges); ranges from jelly-like to hard as a fingernail (keratin)

asexual reproduction in sponges

fragmentation and budding

sexual reproduction in sponges

sperm moves across the reefs and then theres baby sponges

symbiotic microbes

live in cells or mesohyl; bacteria, fungi, and other microbes that live in close, long-term relationships with host organisms

symbiosis

2 unrelated organisms living in proximity

mutualism

both symbiont and host benefit

commensalism

symbiont benefits, host is neutral

parasitism

symbiont benefits, host is harmed

what do sponges feed on

dissolved organic matter (DOM) and particles

adaptations of sponges

high volume filter feeding

habitat of sponges

mostly marine, but also freshwater

germ layers and symmetry of sponges

none

cnidocytes

makes cnides; define the phylum

diploblastic

2 germ layers; ectoderm and endoderm

mode of locomotion in sponges

sessile as adults

symmetry of cnidaria

radial

protosomes/deuterosome of cnidaria

neither

habitat of Cnidaria

mostly marine, but also freshwater

skeletal system of cnidaria

mesoglea, gut cavity

mode of feeding for cnidaria

carnivorous using nematocysts

where is mesoglea thick and thin

thick in medusa; thin in polyp

mesoglea

jellylike layer of hydrated collagen

mode of locomotion for cnidaria

sessile polyps, motile medua

excretion/respiration in cnidaria

diffusion

reproduction in cnidaria

sexual and asexual (budding of polyps and medusa)

distinguishing characteristic(s)

Nematocysts = Cnides which define phylum

adaptations of cnidaria

cnides; symbiotic zooxanthellae allow corals to form reefs

what does the ending -zooid mean

polymorphic colonial animals have units

Portuguese man-of-war

colony of floating polyps; directed by wind all over the ocean and end up on sand

what happens when you step on a man-of-war

you’ll get stinging cells on your ankles; only part when on land; in water, they are worse

class scyphozoa

have both polyps and medusae, but medusa dominates

class hydrozoa

have both polyps and medusae, but polyps dominate

strobilation

scyphistoma forms a series of tiny saucer-like buds (ephyrae) that grow to medusae

class cubozoa

box jellyfish, sea wasp; has potent toxins in cnides; go into anaphylactic shock and digest skin

class anthozoa

includes anemones and reef-building corals; no medusa stage, only polyp; largest biogenic structures on earth

where do reef-building corals live

in a cup of limestone (CaCO3)

who do the reef-building corals have a relationship with

mutualistic relationship with dinoflagellates

zooxanthellae

single-celled, photosynthetic dinoflagellates that live symbiotically within the tissues of many class Anthozoa members

ctenophora

comb jellies, sea goosberries

ctenes

combs in 8 rows move animal weakly in the plankton – made of an “eyelash” of very large cilia

habitat of ctenophora

aquatic, all marine