plankton

Examples of plankton in the following topics:

• Planktonic Food Webs

  • Plankton communities are divided into broad categories of producer, consumer, and recycler groups.
  • Plankton communities are divided into broad categories of producer, consumer and recycler groups.
  • However, determining the trophic level of some plankton is not straightforward.
  • Freshly-hatched fish larvae are also plankton for a few days as long as they cannot swim against currents.
  • Plankton are any water-column organisms that are incapable of swimming against a current.

• Planktonic Communities

  • Plankton (singular plankter) are any organisms that live in the water column and are incapable of swimming against a current.
  • That is, plankton are defined by their ecological niche rather than phylogenetic or taxonomic classification.
  • Although many planktic (or planktonic) species are microscopic in size, plankton consists organisms covering a wide range of sizes, including large organisms such as jellyfish.
  • This scheme divides the plankton community into broad producer, consumer, and recycler groups.
  • However, determining the trophic level of some plankton is not straightforward.

• Prochlorophytes

  • Picoplankton is the fraction of plankton which can be photosynthetic or heterotrophic.
  • Picoplankton is the fraction of plankton, composed by cells between 0.2 and 2 μm, that is either photosynthetic (photosynthetic picoplankton; ) or heterotrophic (heterotrophic picoplankton).

• The Iron Cycle

  • Iron is then assimilated by consumers when they eat the bacteria or plankton.
  • The role of iron in ocean ecosystems was first discovered when English biologist Joseph Hart noticed "desolate zones," which are regions that lacked plankton but were rich in nutrients.

• Gas Vesicles

  • Gas vesicles are spindle-shaped structures found in some planktonic bacteria that provides buoyancy to these cells by decreasing their overall cell density .
  • Gas vesicles provide bouyancy for some planktonic bacteria by decreasing their overall cell density.

• Biofilms

  • The microbial cells growing in a biofilm are physiologically distinct from planktonic cells of the same organism, which, by contrast, are single cells that may float or swim in liquid.
  • Microbes form a biofilm in response to many factors, including cellular recognition of specific or non-specific attachment sites on a surface, nutritional cues, or exposure of planktonic cells to sub-inhibitory concentrations of antibiotics.
  • For instance, the biofilm form of Pseudomonas aeruginosa has no greater resistance to antimicrobials than do stationary-phase planktonic cells, although when the biofilm is compared to logarithmic-phase planktonic cells, the biofilm does show greater resistance to antimicrobials.

• Alphaproteobacteria

  • Aerobic anoxygenic phototrophic bacteria are alphaproteobacteria, widely distributed marine plankton that may constitute over 10% of the open ocean microbial community.

• Newly Discovered Eukaryotes

  • The number of microbial species is not reliably known, but the Global Ocean Sampling Expedition dramatically increased the estimates of genetic diversity by identifying an enormous number of new genes from near-surface plankton samples at various marine locations.

• Biofilms, Persisters, and Antibiotic Tolerance

  • They differ from free-floating or planktonic bacteria that cause acute infections and are managed by antimicrobial drugs.

• Biofilms and Infections

  • Microbes form a biofilm in response to many factors, which may include cellular recognition of specific or non-specific attachment sites on a surface, nutritional cues, or in some cases, by exposure of planktonic cells to sub-inhibitory concentrations of antibiotics.
  • In this context the elucidation of the molecular mechanisms responsible for the switch from planktonic growth to a biofilm phenotype and the role of inter-bacterial communication in persistent disease should provide new insights.