quiz 3- plankton Flashcards
Define plankton as a group
- organisms found generally floating in the water column- some types can swim but not strong enough to oppose currents
- functional group, not taxonomic
phytoplankton
photosynthesizing plankton
Describe the major ecological roles of marine viruses as plankton in the water column.
- nutrient cycling
- pathogens of plankton
Describe the major ecological roles of bacteria as plankton in the water column.
- decomposers- use up oxygen and contribute to oxygen minimum layer
Describe the major ecological roles of fungi as plankton in the water column.
- fungi- important decomposers, also parasites of plankton
Define cyanobacteria and describe their importance in nitrogen cycling.
- “blue-green algae” but actually bacteria
- fix n into ammonium, nitrates + nitrites
Describe similarities in ecological roles across viruses, bacteria, and marine fungi
- nutrient cycling
Diatoms: biological characteristics and ecology
- single-celled protists
- dominate phytoplankton communities in temperate to polar waters
- fit together like a pill box- shells made of silica
phylum and class of diatoms
P: Chrysophyta
C: Bacillariophyceae
Dinoflagellates: biological characteristics and ecology
- protists and single celled (same as diatoms
- dominate subtropical + tropical communities
- some bioluminescent
- can cause harmful algal blooms- cause “red tides”
- generally free-living
- Two flagella: one transverse wrapped around the cell in the groove, the other is perpendicular and runs to the back of the cell
- covered in THECA
- may produce different toxins-
examples of toxins that may be produced from dinoflagella
saxitoxin
- from Alexandrium sp.
- depresses sodium ion transport, impacting nervous system
- kills filter-feeding bivalves, and potentially humans that feed on them
brevotoxin
- Katerina Brevis species
- cause of TOXIC red tides
- also binds to sodium channels, but RARELY fatal to humans
Dinoflagellates Phylum and class
P: Pyrrophyta
C: Dinophyceae
Diatoms: life cycle
- sexual + asexual (binary fission) reproduction
- diatoms get smaller after each division- at a certain size, a gamete is produced
- auxospores- cell increases in size, casts of small valves and replaves them with larger valves
- asexual repro helps them form large blooms very quickly
- can also create ASEXUAL RESTING SPORES- fall to seabed and wait out poor envi conditions b4 developing
Dinoflagellates: life cycle + resting stages
- asexual (binary fission) and sexual repro
- temporary cysts- resting stages- sink to ocean floor until conditions are favorable and they can begin development
theca
series of CELLULOSE PLATES covering dinoflagellates, important for helping to identify them
what are zooxanthellae
dinoflagellates
NOT free-living- within host tissue
Coccolithophores Phylum
Chrysophyta
Coccolithophores- about
Phytoplankton
tropical open ocean
Massive bluish-white blooms- can be seen from space!
Coccolithophores- bio char.s
- spherical
- covered in coccoliths (but not all of them are- some “naked” coccolithophores)
what are coccoliths?
plates covering Coccolithophores
CALCIUM CARBONATE
make up 1/3 of total Ca Carbonate production in the ocean!
Zooplankton
Not photosynthesizers- heterotrophs
- next level of food chain above phytoplankton or a bit higher- important parts of lower levels
Crustacean zooplankton: characteristics, ecology
Chitin skeleton
Body skeleton
Paired, jointed appendages
types: COPEPODS, KRILL, larval crabs, shrimp, & lobsters
crustacean zooplankton Phylum and Subphylum
Phylum Arthropoda
Subphylum Crustacea
Phyla of Gelatinous zooplankton
- phyla Cnidaria, Ctenophora, chordata
Copepods
- Crustacean zooplankton
- Plankton from SpongeBob
- Dominate nearly all oceans- largest mass of any plankton type
- feed on phytoplankton, organic matter in water column, smaller plankton
Copepods Phylum, Subphylum, Order
Phylum Arthropoda
Subphylum Crustacea
Order Copepoda
Copepod life cycle
Eggs
Naupliar stage (6 stages)
Copepodite stages (teenager)
Adult
2 major copepod families
calanidae
eucalanidae
Unique part of life cycle of Calanidae and Eucalanidae
DIAPAUSE stage (move into deeper water, like hibernation- arrested development)
OR may produce DIAPAUSE EGGS
BETWEEN COPEPODITE and ADULT stages
chem/physical oceanic importance of diapausing
MAY be responsible for sequestering more carbon than any other biogeochemical process
Sp. example of diapausing
Calanus finmarchius
form dense layers that attract north atlantic right whales
Krill
Crustacean zooplankton
- dominant in Antarctic Ocean
- feed on phytoplankton and small zooplankton
- main food source for marine mammals and birds
- important carbon sinks
- sea ice melting affects them (I’m unsure how)
- krill can swim and SWARM- move away from predators or toward prey
- all bioluminescent except for one family
Order of krill
Euphasiaceae
Phylum Cnidaria, class scyphozoa
True jellies
- gelatinous zooplankton
- contract bell to swim
- feed on phytoplankton, zooplankton, small fish
- capture food via stinging/sticky nematocysts
Phylum and class of true jellies
Phylum Cnidaria, class scyphozoa
Phylum Cnidaria, class hydrozoa
- gelatinous zooplankton
- SIPHONOPHORES
- COLONIAL animals
- long, thin, transparent
- many have nematocysts
- eat copepods, small crustaceans and small fish
- eg: PORTUGUESE MAN O WAR
Phylum and Class of Siphonophores
Phylum Cnidaria, class hydrozoa
the four polyps of the siphonophore portuguese man’o’war
Pneumatophore- gas-filled
Dacilozooids- on tentacles, covered in nematocysts
Gastrozooids- digestive
Gonozooids- reproductive
Phylum Ctenophora
- gelatinous zooplankton
- comb jellies
- rows of teeth
- Digest externally with secreted enzymes
Phylum chordata, subphylum tunicata
- gelatinous zooplankton
- tunicates!
- chains of individuals: blastozooids (each of these reproduce sexually)
- have an asexual solitary phase
Phylum foraminifera
- NOT gelatinous zooplankton
- PROTISTAN zooplankton instead
- external CALCIUM CARBONATE skeleton
Can stream out their cytoplasm thru pores in their shell to capture bacteria and phytoplankton
(more closely related to diatoms + dinof.s than other zooplankton)
Phylum Chaetognatha
- ARROW WORMS
- MACROPLANKTON
- torpedo-shaped
- some produce a deadly neurotoxin- tetrodotoxin
Pteropods phylum, class, order
Phylum Mollusca, class Gastropoda, order Pteropoda
angels vs butterflies
butterfly- shell
eat marine snow- capture w a sticky net
angel- no shell (feed on butterflies)
Diatoms are found in the Phylum ______
Chrysophyta
A group of zooplankton that utilize contractile pseudopodia to capture their food are called _______
Foraminiferans
Diatoms are encased by a _____ shell called a _____. (They get smaller in size as diatoms reproduce asexually.)
- silica
- valve
TRUE OR FALSE: Diatoms can produce an auxospore in nutrient poor conditions, which fall to the seafloor and can remain dormant until favorable conditions return. FIX IF FALSE
FALSE
- Diatoms can produce a TEMPORARY RESTING SPORE in nutrient poor conditions, which fall to the seafloor and can remain dormant until favorable conditions return.
TRUE OR FALSE: Diatoms can undergo sexual reproduction by releasing gametes. This often occurs once the individual gets too small to reproduce asexually. FIX IF FALSE
TRUE
Diatom valves can be covered in _____, _____ and/or _____
- spines
- pores
- ridges
neuston
float on top or live right under the surface
includes microscopic organisms that use surface tension
pleuston
float by buoyancy
macroscopic organisms
