Marb 435 1st Edition Lecture 3Outline of Current Lecture Introduction to information about zooplankton life cycles and preparation for zooplankton lab.Current Lecture: Plankton Terms to know1. Plankton- Drifting organism that inhabit the water column of seas, oceans or lakes- Passive transport with currents - Often capable of vertical migration in the oceans water columns2. Neuston- Type of plankton that is specifically associated with the uppermost layer of the water column; at the surface or just below3. Nekton- Organisms that live in the water column of seas, oceans and lakes and can propel themselves independently of the water currents4. Phytoplankton- Photosynthetic protists and bacteria and archaea- They are the primary producers in the ocean and are extremely ecologically important5. Zooplankton- microscopic, unicellular and multicellular organisms with heterotrophic nutrition that are capable of vertical migrations in the water column6. Holoplankton- spend their entire lives in planktonic form7. Meroplankton- are planktonic for only part of their life cycles, often are the larvae of many marine invertebrates.8. Planktotropic- feeds on other planktonic organisms, long larval phase9. Lecithotropic- feeds on yolk supplied with the egg, short larval phaseZooplankton Size Classes:- Microzooplankton- 20 to 200 μp- Mesozooplankton-0.2 – 20 mm Copepods often represent 50-90% of the catch- Macrozooplankton- 2-20 cm Less abundant than smaller plankton, and less susceptible to capture. Examples include: larval fish, shrimps, and salpsThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Pros and Cons of Larvae Dispersal Potential advantages of dispersal by larvae: Reduces overcrowding Allows colonization of new habitats Promotes genetic exchange between populations Avoiding competition with adults Risks of dispersal by planktonic larvae: Limited yolk reserves might not last and larva may starve High risk of predation (Manta rays, whale sharks and baleen whales are pelagic plankton predators.Many benthic invertebrates also feed on plankton) Larvae might never find suitable habitat to settle Live in viscous, liquid medium in which locomotion is difficultDefenses plankton have against predation Transparence Protective Spines Chemical Defenses: distasteful or toxic EXAMPLE: Small amounts of didemnins from larvae or adults of the Caribbean tunicate Trididemnum solium cause vomiting in fish Diel swimming rhythms Synchronized mass spawning Abbreviated larval phasesZooplanktonic Feeding and Motion in Water Column Zooplankton are usually suspension feeders of phytoplankton, bacteria and suspended organic matter They generally use cilia and mucus for food capture (except for arthropods which use setae) May be passive filter feeders or may actively pursue particle Zooplankton can move through use of cilia, jointed appendages, or whole body contractions Most zooplankton can actively control their vertical position in the water column by using directed swimming and also slight changes in buoyancy Many species aggregate in deeper waters during the day and rise at night for feeding and some leave the bottom for mating (e.g. swarming polychaetes)Things you also need to know:Alastair Hardydesigned the first Continuous Plankton Recorder (CPR) in the 1920s (which was a device that was towed behind boats to capture plankton continuously)CO2 forms bicarbonate (HCO3-) and carbonate (CO32-) in seawater, and that lowers the pH.Increase in atmospheric CO2 from pre-industrial 280 μatm to 370 μatm has decreased surface ocean pH by ~0.12 units to current 8.2. The possible effects of this change on planktonic life are hard to