Poriferans, Cnidarians, and Ctenophores Flashcards
WHat are the cell layers of poriferans?
Totipotent cells
* Pinacoderm
* Pinacocytes
* Choanoderm
* Choanocytes
* Mesohyl
What are totipotent cells?
cells that can form all types of
cells in body
What are pinacoderm cells?
outer surface** layer**
What are pinacocytes?
outer surface cells
What are choanoderms?
inner surface layer
What are choanocytes?
inner surface cells, flagellated
What is the mesohyll?
the layer inbetween the outer and inner layers
What are the tissue layers of poriferans?
They have no real tissue. Their whole body is a single tissue
What are ostita?
pores
What are amebocytes?
Pick up and **distribute **nutrient particles from
water flow through the
epithelium
What are choanocytes?
Move water into
epithelium (outside
protective layer)
What is an osculum?
where water exits
What are organic poriferan skelletons made of
collagen
What are in-organic poriferan skelletons made of
hydrated silicon dioxide or calcium** c**arbonate
What are spicules?
Skeletal elements made of Calcium-carbonate
or silicon dioxide, and/or collagen
* Produced by mesohyl cells
What are the functions of spicules?
Provide support
* Regenerate
* Defense against predators
What are coral reefs?
Cnidarians:Anthozoa
What are Neumatocysts?
stinging tentacles with cells for capturing prey
What are sessile polyps?
attached form with mouth and
tentacles positioned upwards
What are medusa polyps?
free-swimming form that is
transported by water currents, mouth with
surrounding tentacles positioned
downwards
What are corals?
Single or colonial polyps without a medusa
What do corals often contain?
symbiotic zooxanthellae, symbiotic dinoflagellates
How do corals feed?
The coral zooxanthellae produce organic matter through photosynthesis.
* Some of this organic matter is passed to the coral.
* They also use their neumatocysts
* **mesenterial **filaments
What are coral reefs?
an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate.
What type of coral makes coral reefs?
Hermatypic (hard corals)
What type of coral doesn’t make coral reefs?
Ahermatypic(soft corals)
What do corals eat?
plankton and
other small prey
What are mesenterial filaments?
**filiments **that secrete digestive enzymes
allow coral to feed and digest outside body
What are the types of coral reefs?
Fringing Reefs
Barrier reefs
Atolls
What are atolls?
ring-shaped island, including a coral rim that encircles a lagoon.
What are barrier reefs?
a reef that is separated from the main coast by a deep channel or lagoon
What are fringing reefs?
grow near the coastline around islands and continents.
separated from the shore by narrow, shallow lagoons.
most common type of reef.
What are ideals for coral growth?
- Hard substrate
- Narrow temperature range
- Narrow salinity range
- Optimal light for zooxanthellae
- Low sediment load in water
- Calm water
- Low pollution levels
- pH
What is coral bleaching
expulsion of zooxanthellae due to global warming
How do hydroids reproduce
Sperm are released into the sea and eggs are fertilized within the female gonophores where the** embryos develop** into planulae.
What are aqueous systems in proferians?
Water channels
* Transports food, oxygen, waste
products, reproductive products,
hormones
* Filters its own volume every 10-
20 second
How do proiferans reoroduce asexually?
buds break off
and grow into a new sponge
How do poriferans reproduce sexually?
sperm are** released into
the water (broadcast spawning) to
be picked up by a nearby sponge**
and directed to egg.
* Most** sponges** are hermaphrodites
(produce both sperm and eggs).
What are the classes of poriferans?
Class Calcarea
Class Hexactinellida
Class Demospongiae
What is class calcera
spicules made of Calcium carbonate
What are Class Hexactinellida
spicules made of slicon dioxide,
6-rayed
What is Class Demospongiae
spicules made of slicon dioxide,
not 6-rayed,
sometimes collagen
How do cnidarians reproduce asexually?
Polyps reproduce by
budding
How do cnidarians reproduce sexually?
In some cnidarians:
medusa is the sexual
stage, releasing eggs and
sperm.
– Fertilized egg results in a
zygote, which develops
into a swimming larva,
the planula.
* The planula settles on the
bottom to form a colony
of polyps.
– New medusae are
formed by mature colony
What are hydroids?
Most consist of colony of polyps, with small
reproductive medusa.
What are Siphonophores?
hydrozoans that form
drifting colonies of polyps; Colonies of polyps that
all work together and play different roles for survival
What are class cubozoa?
Cubomedusae:
– Small medusae with tentacles armed
with very powerful nematocysts that may
cause death in humans
What are scyphozoa?
large jelly fish:
* Weak swimmers
* Contract and
pulsate bell (body)
* Tentacles
What are geological importance of coral reefs?
often massive physical
structures
What are the biological importance of coral reefs?
biological structure,
High diversity
What are the ecological importance of coral importance?
shoreline protection,
harbors, fishing,
tourism
What is white band disease?
affects acroporid corals, perhaps gram negative bacterium, not isolated yet
What is white plague?
rapid degradation of
corals, gram negative bacterium,
cultured in lab and infects corals
What is black band dsease?
affects, non-
acroporid corals, consortium of
microorganisms, leads to sulfide
accumulation and toxicity to corals
What are ctenophora?
comb jellies:
– 8 rows of ciliary combs that
beat continuously
– Radial symmetry
– No nematocysts
– Long sticky tentacles used to
capture prey
– About 100 species, all
marine, mostly planktonic
