Geos 212 1st Edition Exam 3 Study Guide Following are the main topics that we have covered since Exam 2 In addition to the terms and concepts listed below please make sure you are familiar with the large scale processes that we have discussed for example realize that ocean productivity starts with upwelling bringing nutrients to the surface etc Also become familiar with the diagrams that we have used in class and on homework Three components of life organic materials o fluids gases tissues energy source o Photosynthesis plants sunlight o Respiration Animals organic matter and food o Chemosynthesis bacteria hydrogen sulfide genetic information o Mostly DNA Information from ancestors through DNA DNA s double helix structure can unzip to make copies and is the mechanism by which geneticc information is passed from parents to offspring Main chemical elements in marine organisms what they are used for where the elements originate and how organisms acquire them The organic materials of marine organisms are mainly comprised of carbon C hydrogen H Oxygen O and Nitrogen N They are used for building organisms tissues and carrying out metabolic processes These elements originate from food sources the organisms consume and ultimately the soil Energy sources for marine organisms photosynthesis chemosynthesis and respiration energy sources o Photosynthesis plants sunlight o Respiration Animals organic matter and food o Chemosynthesis bacteria hydrogen sulfide History evolution of life on Earth from handout attached main things we concentrated on The age of the earth is 4 6 billion years old or 4600 million years old The Cambrian explosion refers to a great radiation of species diversity which occurred roughly 540 million years ago Whales evolved around 50 million years ago from previously land dwelling mammals that took to the sea Basics of evolution environments change genetic changes gradual vs rapid evolution extinctions 1 The environment changes and organisms need to adapt 2 DNA accumulates mutations that organisms with mutations that confer beneficial adaptations survive and pass on their genes resulting in a change in genetic information and evolution 3 Gradual evolution is always happening every once in a while a rapid diversification occurs when the environment changes rapidly EX Cambrian Explosion 4 Organisms that cannot adapt to their changing environment fail to reproduce and go extinct Physical factors list came from class that control distribution of life things like light pressure temperature density salinity dissolved gases nutrients and productivity 1 2 3 4 5 6 7 8 9 10 Food resources nutrients Currents Temperature of water sun CO2 Salinity Wind Pollution Predators Clarity Energy wave action Also realize importance of tides waves predation upwelling downwelling El Nino La Nina Distribution of productivity with depth in map view and through the seasons You should be able to take a map of productivity and explain all variations Tides and waves affect the migration of live throughout the ocean and allow for mobility Predation and or lack thereof can cause notable increases decreases in prey populations This can have negative positive or neutral effects on the ecosystem Upwelling can create a nutrient rich environment while downwelling can be responsible for nutrient poor waters El Nino La Nina may contribute to changes in water temp and tides which may affect life The deeper in the ocean you move the less productivity there is More productivity where there is upwelling Food webs who are primary producers what do they depend upon they are the base of the whole food web phytoplankton diatoms quarts coccoliths calcite Depend on energy source e g sun or chemistry who are the primary consumers what do they eat Are animals which eat primary producers Copepods krill zooplankton what is a secondary consumer Animals which primary consumers or others lower on the food web Blue whales sperm whales sea birds seals what is a top carnivore Top of the food web and eats anything lower than it not eaten by anything food web for Antarctica attached Kelp Forest What temperature water Nutrient levels Where do you find them What kind of plant are kelp Strategies for staying close to surface attached to sea floor Food web Cold water High nutrient level high productivity Found in high latitudes Not at equator because it is too warm there Kelp are algae Kelp attach to sea floor with a holdfast and use bladders to float leaves Primary producer Mangrove Forest What temperature water Nutrient levels Where do you find them What kind of plant are mangrove structure of mangrove tree Strategies for surviving waves hurricanes Food web Warm water Low nutrients downwelling found at equator low latitudes Plant with leaves in the air at intertidal zones strong roots allow them to survive waves hurricanes Primary producers Coral Reef communities where do you find them Structure of coral plant animal how nutrients are cycled how reef is constructed reproductive strategies origin of coral reefs origin of atolls Water temperatures nutrient levels Where and when are the oldest coral fossils Current threats to coral reefs including causes and effects of bleaching and acidification They are found near the surface in warm water low productivity areas low nutrients Two occurrences 1 continental shelves 2 volcanic islands Polyp of coral animal part and the symbiotic zooxanthellae photosynthetic bacteria are plants All nutrients are recycled in coral reefs because there is little nutrients and wasting them cannot be tolerated In juvenile phase corals are meroplankton mobile and can disperse Coral reefs originated in an ocean that no longer exists the oldest coral fossils Threats to coral reefs are coral bleaching due to warm water killing symbiotic bacteria and CO2 corrosion due to ocean acidification dissolve the skelatons of many marine organisms Planktonic plants phytoplankton mainly diatoms most abundant plant on earth Planktonic animals planktonic as juveniles meroplankton coral communities versus always planktonic holoplankton examples krill and copepods are most abundant Life cycle of fish and many crustaceans like lobster 4 stages when planktonic and when swim walk reproductive strategies and survival rates 1 2 3 4 Eggs Larvae planktonic Juvenile swim walk Adult swim walk Survival rate is very low very few juveniles make it to adulthood and reproduce Fisheries what are they effectiveness benefits of good management