ocean ch 13

why is photosynthesis important to the oceans biomass?

99.9% of the oceans biomass directly or indirectly relies on photosynthesis as its source of food

what is photosynthesis?

A process used to convert light energy from the sun into chemical energy in the form of organic compounds.

What is Red Tide and which organism produces it

Red tides- harmful algal bloom. Associated with toxins, fish kills, human illness

what is chemosynthesis?

When organisms use chemical energy to produce carbohydrates.

what are nutrients and how are they supplied to the ocean?

a substance that provides nourishment essential for growth and the maintenance of life; nutrients are supplied through the process of upwelling

what factors affect primary production?

ability of nutrients and solar radiation

How would you describe the transfer of energy between trophic levels?

each step up = larger organisms but fewer individuals and smaller total biomass otransfer efficiency between steps = 10 %

define overfishing

fish stock harvested too rapidly ; majority of population is sexually immature and cannot reproduce **decreasing fish catch size**

How do human activities contribute to Eutrophication and Harmful Algal Blooms?

human activities have been shown to contribute excess nutrients in the form of fertilizer, sewage, animal waste in coastal water

where in the ocean does chemosynthesis occur?

in the deep ocean

define Incidental catch (bycatch)

marine organisms taken accidentally by fishing for commercial species (includes birds, sea turtles, dolphins, sharks); nearly ¼ of total catch

define Maximum Sustainable Yield (MSY)

maximum catch that can be taken without overfishing; fishery ecosystem can still be maintained

what two factors affect the oceans color?

the amount of turbidity from runoff and the amount of photosynthetic pigment

what is meant by primary productivity?

the rate at which organisms store energy through the formation of organic matter

what is the euphotic zone?

the zone where there is enough light to support photosynthesis

What are some problems with marine fisheries management?

•Fishing industry suffers from overfishing, wasteful practices which produce large amount of bycatch, and lack of adequate fisheries management. •In some locations fish are becoming so scarce that fishing effort costs more that what catch is worth! •Government subsidies make up shortfall

What is the difference between a food chain and a food web?

•Food chain = linear feeding relationship between producers and one or more consumers •Food Web = branching network of feeding relationships among many organisms

What are some examples of microscopic and macroscopic algae?

•Macroscopic Algae: (seaweeds): Brown algae- mostly found in temperate and cold water (bull kelp - one of largest). •Microscopic algae: diatoms - class of algae with silica tests which contain a single cell

What are the roles of producers, consumers, and decomposers and what are some examples of each?

•Producers (algae, plants, etc.)- photosynthesis or chemosynthesis •Consumers (herbivores, carnivores, omnivores) - eat other organisms •Decomposers (bacteria)- break down detritus

What are some feeding strategies of marine organisms?

•Suspension feeding or filter feeding=Take in seawater and filter out usable organic matter •Deposit feeding=Take in detritus and sediment and extract usable organic matter •Carnivorous feeding=Capture and eat other animals