Life in Water Flashcards
How much of the Earth’s surface is covered in water?
71%
Ocean’s contain this % of water:
97
Freshwater in lakes, streams, and ground water make up less than this % of water:
1
What are biological zones in freshwater systems associated with?
Velocity, depth, temperature, clarity, and chemistry of the water
Define lotic vs. lentic systems and give examples of each.
Lotic systems are flowing water systems such as streams and rivers, while lentic systems are stationary systems such as lakes and ponds.
What is the difference between riffles and pools?
Riffles have faster water movement with coarser particles, while pools have slow water movement with finer sediments.
What are the four major feeding groups in rivers and streams?
Shredders, collectors, grazers, and gougers
How are lakes formed?
Either by: glacial processes, river oxbows, volcanic craters or animal/human activities.
Why must organisms present in estuaries be adjusted to varying salt concentrations?
Due to estuaries being at the junctions of rivers and oceans, so the salinity varies as freshwater flows in from river and salt water flows in from the sea.
_______ covers less than 1% of the seafloor but house a quarter of marine species
Coral reefs
How is kelp abundance influenced by organismal interactions?
Sea urchins eat kelp, sea otters eat urchins, and sea otters are eaten by orca and eliminated by humans
How is energy supplied below the photic zone?
Energy is supplied by carcasses and sinking nutrients/organic matter because photosynthesis cannot occur
How do organisms in the pelagic-zone prevent sinking out of photic zone?
By floating either through swimming or by having gas filled bladders
What conditions are characteristic of the benthic zone?
Very cold and high pressured with sparse populations
