Unit 5 Terms - Cnidaria and Ctenophora Flashcards
- Name means “water serpent animal”
- includes: Hydra, Obelia, Physalia
- medusa have velum
Class Hydrozoa
- name means “ cup-animal”
- includes: Aurelia
- no velum in medusa
Class Scyphozoa
- name means “flower animal”
- includes: corals (like: Gorgonia and Tubipora) and anemones (like: Metridium)
- no medusa stage
Class Anthozoa
an explosive cell containing one giant secretory organelle or cnida
cnidocyte
- organelle that can be discharged from its cell
- can be stinging or adhesive
- more than 20 varieties, but most common is nematocyst
cnida (plural = cnidae)
- stinging cnida
- used to inject toxin
nematocyst
lid-like feature on a nematocyst
operculum
trigger on a nematocyst, made from a modified cilium
cnidocil
a diffuse nervous system, nerve cells equally dispersed around the body
nerve net
the root-like base seen in a colonial hydrozoa such as Obelia
hydrorhiza
the stalk of a colonial hydrozoa such as Obelia
hydrocaulus
the inner, living/cellular part of the stalk (hydrocaulus)
coenosarc
the outer, non-living chitinous sheath of the hydrocaulus
perisarc
the feeding polyp seen in a colonial hydrozoa such as Obelia
hydranth
reproductive polyps seen in a colonial hydrozoa such as Obelia
gonangium
a shelf projecting inward from the margin of the bell in a medusa
velum
tubular extension for mouth; often seen in medusa of Hydrozoa
manubrium
specialized sense organ for equilibrium
statocyst
light-sensitive organ
ocelli
conical elevation that bears mouth; seen in Hydra
hypostome
- when chemical breakdown of food takes place outside of cells
- digestive enzymes breakdown food particles in a body cavity
extracellular digestion
food particles are drawn into cells by pseudopodia and then chemically broken down with the cell
intracellular digestion
- columnar cells with laterally extended bases
- found lining the gastrovascular cavity
- the bases form a circular muscle layer
nutritive muscular cells
- cells that make up most of the epidermis
- serve as both a covering and as a longitudinal muscle layer
epitheliomuscular cells
- cells that are undifferenitated
- can transform into other types of cells if necessary
interstitial cells
cnidocytes with cnidae that penetrate prey and inject toxin
penetrant
cnidocytes with cnidae that recoil and entangle prey
volvent
cnidocytes with cnidae that secrete adhesive substances for attachement
glutinant
method of asexual reproduction in most cnidarians
budding
ciliated, free-swimming larva seen in most Scyphozoan jellies like Aurelia
planula
- part of the life cyle of Scyphozoan jellies like Aurelia
- hydra-like polyp
- may bud to produce polyp clone
scyphistoma
- part of the life cyle of Scyphozoan jellies like Aurelia
- made up of a series of cup-like buds
strobila
- part of the life cyle of Scyphozoan jellies like Aurelia
- individual saucer-like buds produced by strobilation
ephyra
- small pieces of a pedal disc break off and become new individuals
- asexual reproduction seen in anthozoans like the anemones
pedal laceration
dinoflagellates found living as benefitial partners with many cnidarians like corals
zooxanthellae
when corals lose their zooxanthellae and become white and brittle
coral bleaching
a reef close to a landmass either with no lagoon or a narrow lagoon
fringing reef
a reef with a wide lagoon between it and the shore
barrier reef
a reef that encirlces a lagoon but there is no landmass or island anymore
atoll
