Flashcards in Test 1 Deck (95)
Why study marine biology?
It is the study of plants, animals, and other organisms that live in the ocean. Marine life represents an enormous source of human wealth such as food, medicine, raw materials (algae) and recreation.
How can marine organisms create problems for humans?
Shellfish poisoning; ciguatera poisoning; shark attacks; erosion of structures we build (piers, sea walls), fouling of ship bottoms
Fundamentals of Marine Bio
Marine life helps determine the very nature of our planet
Marine organisms produce much of the oxygen we breathe (helps the earth's climate)
Shorelines are shaped and protected by marine life
- Calcium carbonate sand deposition
- kelp beds
How long ago did life appear in the ocean?
3.8 billion years ago
Animal and plant life?
Extant today, had ancestors that evolved 500 million yrs ago
How old is earth?
4.7 billion years old
Supercontinent = Pangea: suggests that all the continents had once been joined
- Glomar Challenger 1960's
- sediment cores (more sediment further away from ridges)
- magnetic signature of crust
Sea floor spreading?
Deep sea vents
Earth's crust divided into a number of irregular plates;
Thermophilic and chemotrophic bacteria
The major wind fields of the atmosphere push the sea surface creating currents
The marine environment is divided into zones according to (3 things)
distance from land; water depth; and whether the organisms are benthic or pelagic
pelagic environment that lies over the shelf (also called the coastal zone)
Pelagic waters beyond (seaward) the shelf break
shallowest zone, plenty of light for PS
not enough light for PS
flat abyssal plain; trenches
live on (epifauna) or buried in (infauna) the bottom
some are sessile (attached) some move around (mobile)
up in the water column
away from the bottom
Plankton move at the _
mercy of the currents
planktonic plants and other autotrophs are carried from place to place
animals that can swim out of currents such as fish, marine mammals, squids, and large jellyfish
Water accounts for _% of the volume of most marine organisms;
Water provides _ and _ _ for
buoyancy and body support for swimming and floating; reduced need for heavy skeletal structures
Properties of seawater
Water is a universal solvent
High heat capacity (slow change in temp)
Density temperature relationships (>4oC density increases with decreasing temperature)
<4oC density temperature pattern reverses
Increased viscosity (affects sinking)
Properties of seawater part 2
Heat capacity: In the sea heat is transferred from place to place by
subtle conduction (molecular exchange of heat, ie., photons impart energy to water molecules)
Used by marine organisms for vision and PS (euphotic zone)
The _ of the _ _ is determined by how rapidly seawater _ _ and _ it to _ _.
depth; photic zone; absorbs light; converts; heat energy
Factors that diminish quantity/intensity of light available for PS activity include:
concentrated plankton populations
clouds, dust, fog
angle of incident light/reflection
season, time of day, latitude
High heat capacity: limits marine temperatures to a much narrower range than land temperatures.