Ch.12: Plankton
Ctenophores:
"Comb jellies" • Not true jellyfish: no stinging cells- use cilia plate (comb rows) to catch food • Many bioluminescent/iridescent • Recently discovered to have a 'complete" digestive tract (having a complete digestive tract is very efficient)
If you catch a 1000lb shark, and it's 3 trophic levels higher than phytoplankton, how many pounds of phytoplankton would it take to support that one shark?
1,000,000 (a million pounds)
What is meant by trophic efficiency?
10% energy (biomass) transfer from lower to higher trophic levels • 90% energy lost between levels • every time you go up the food chain, some carbon and energy is lost
Nano plankton:
2-20 microns
Picoplankton: 2-3 microns; 1/100th diameter of human hair; most common plankton is Prochlorococcus
2-3 microns; 1/100th diameter of human hair; most common plankton is Prochlorococcus
Macro plankton:
200 microns- 2mm; visible to naked eye
Chaetognaths:
AKA arrow worms • Voracious predators on zooplankton • Can wipe out entire cohort of fish larvae • Strong association between species and water mass (can ID water mass by ID species)
Radiolarians:
Amoeba-like protozoans • Tests (shells) of silica
Foraminifera's:
Amoebas with shells (protrude through holes) • Shells of calcium carbonate • Useful environmental indicators: great for assessing climate change, sea level, etc., also for locating oil deposits
Why are microbes such an important part of marine nutrient cycling?
Drive most of the biogeochemical cycles in the ocean
What are some marine plants and what are there adaptations to tolerating salt?
Halophytes: salt tolerant plants • Cordgrass: in marshes • Mangroves: red mangroves- prop roots; blocks salt uptake (water is saltier round roots and they have sacrificial leaves) Black mangroves- pneumatophores (like snorkels)- exudes salt from leaves White mangrove- furthest inland • All are marine nurseries: places for animals to hide and grow
Give examples of macro algae and where they are found.
Large, plantlike algae: don't make flowers (most are benthic) • Some are not benthic: Sargassum • Some are attached but have floats: Kelp
How can the Redfield Ratio be used to measure production?
O2:C:N:P= 109:41:7:2:1
Explain the light bottle dark bottle technique to measure primary productivity
Often use collection bottles at various sites and depths • Measure change in O2 with depth or use carbon-14 as tracer • Keep water at same light and temperature with clear vs. dark bottles • Look at differences between light and dark bottles= amount lost to respiration
Explain how to measure primary productivity in the oceans.
Oxygen production directly related to the amount of CO2 consumed (find one to determine the other)
Why do phytoplankton have pigments other than chlorophyll a?
Phytoplankton are primary producers • They use pigments to convert sunlight and inorganic matter into organic matter • Their other pigments, although chlorophyll is the most abundant, can absorb more wavelengths
What are the categories of plankton based on energy uptake?
Phytoplankton: Zooplankton: Bacterioplankton:
What are the different size categories of plankton?
Picoplankton: Nano plankton: Micro plankton: Macro plankton: Mega plankton:
Hydrozoans:
Some look like jellyfish, but are in a different Class Some mostly medusae, some mostly polyp, some both at the same time • Box Jellyfish: Cubozoans, not true jellies Square body, 4 tentacles or clusters Fast swimmers Eyes! With lenses Swarm Attracted to movement/shadows Extremely toxic (death in <2 minutes for some)
What are the disadvantages of an animal possessing a planktonic life stage?
Starvation • Predation • Currents and eddies • Very low chance of making it
Make a marine trophic pyramid and label each tier. What is the energy conversion rate from one level to the next? What happens to the "lost" energy?
The bigger the base, the bigger the top
Why are there few marine plants?
Very few because most cannot tolerate salt
12. What role do viruses play in the microbial food web?
Viruses are major pathogens of marine microbes • When they kill microbes, cell is lysed and releases DOM • Extremely abundant: if all were laid out end to end, would reach further than the nearest 60 galaxies
Micro plankton:
aka net plankton; 20-200 microns; easy to catch with plankton net
What are HAB's? What causes them? What are some examples and their effects on humans?
any phyotoplankton that causes harm to humans or the environment- toxic, too much biomass, etc. • Most are dinoflagellates • Ecologically disruptive algal blooms (EDABs) disrupt ecosystem function • Nasty toxins: paralysis, amnesia, death
Zooplankton:
anything that isn't phytoplankton; heterotrophs
Bacterioplankton:
bacterial plankton
Mega plankton:
big stuff; jellies, etc.
Ciguatoxin-
ciguatera fish poisoning; nervous system damage (vertigo, hot feels cold)
What is DOM?
dissolved organic matter- from phytoplankton and zooplankton
White mangrove-
furthest inland • All are marine nurseries: places for animals to hide and grow
Cordgrass: in marshes
in marshes
Food chain:
linear depiction of predator-prey interactions • Each step is a trophic level
Food web:
multiple food chains interlinked; flow of nutrients and energy between groups of organisms
Brevetoxin-
neurotoxic SP; food poisoning
Seagrass:
only fully marine flowering plant
Saxitoxin-
paralytic SP: paralysis, respiratory failure, death
Phytoplankton:
photosynthesize
Black mangroves-
pneumatophores (like snorkels)- exudes salt from leaves White mangrove- furthest inland • All are marine nurseries: places for animals to hide and grow
red mangroves
prop roots; blocks salt uptake (water is saltier round roots and they have sacrificial leaves)
Mangroves:
red mangroves- Black mangroves- White mangrove
Holoplankton:
spend whole life as plankton • Nearly all phytoplankton, some zooplankton • Most protists, some animals (siphonophores, comb jellies, etc.)
Gross primary production:
total amount of organic material made by photosynthesis
Shellfish poisoning:
toxins concentrated in shellfish (bad results)-
Meroplankton
usually spend early life as plankton, become nekton/benthic later • Some jellyfish spend early life as benthic, adult as plankton • Many animals- corals, crabs, lobsters, shrimp, mollusks, worms, fish, etc
Net primary production:
what is available for consumption by heterotrophs • = Gross production minus respiration by photosynthesis
Coccolithophorids:
• Cell wall has plates of calcium carbonate • Can form large blooms: visible from space • Chalk is made from them
Dinoflagellates:
• Cell wall: plates of cellulose (armored) or no plates (naked) • Includes autotrophic, mixotrophic, and heterotrophic members • Possess two flagella; strong vertical swimmers • Most likely to cause harmful algal blooms and bioluminescence • Some are coral symbionts= zooxanthellae
What are the advantages of an animal possessing a planktonic life stage?
• Dispersal • Less competition with parents • Colonization • Genetic variation • Cheap, easy- make lots of babies
Diatoms:
• Extremely abundant (40% marine primary productivity) • Cell wall: frustule, made of silica exhibit radial or bilateral symmetry • When division occurs, one of the daughter cells gets smaller; eventually sexual reproduction allows the cells to return to the original size (like a petri dish) • Useful in diatomaceous earth, filtration, and abrasives, toothpaste
Crustaceans:
• Holoplankton: copepods- first level consumers Krill- little bigger than copepods, longer lived (3 years), are not shrimp, food for some really big animals • Meroplankton: crabs, lobsters, shrimps, barnacles, many others
Cnidarians:
• Jellyfish: true jellyfish "Scyphozoans Stinging cells (cnidae) Some get rather large (7ft across, 100ft long) Sexually reproducing medusa (jellyfish) stage; asexual polyp (anemone-like) stage is benthic Mouth and anus are the same opening... awkward
Cyanobacteria:
• Prokaryotic photoautotrophs (AKA blue-green algae) • Small, but make 1/5 primary production in oceans • Like-nutrient-poor waters • Can fix nitrogen from atmosphere (N2 to NO3)
