Marine Biology Lecture Notes Review

Flashcards covering the history of marine science, ocean floor features, currents, marine biology adaptations, habitat types, and human impacts based on the course transcript.

Aristotle

Early scientist known for his early natural history observations.

Carl Linnaeus

Scientist who developed the foundations for taxonomy and classification.

Coral Reef Subsidence Theory

Charles Darwin's theory that volcanic islands sink from cooling and tectonic shifts while coral grows upward.

Alfred Russel Wallace

Scientist who studied biogeography and identified the Wallace Line.

Azoic Theory

Proposed by Edward Forbes, it stated that no life could exist below a specific depth limit.

HMS Challenger Expedition

The first global oceanographic expedition.

Sylvia Earle

Known as "Her Deepness," she is a pioneer in deep sea exploration.

Ring of Fire

A region around the Pacific Ocean characterized by high marine biodiversity, deep-sea trenches, island formation, and hydrothermal vents.

Continental shelf

A shallow, gently sloping region extending from the coast that is the most biologically productive region of the ocean.

Continental slope

A steep drop-off connecting the shallow shelf to the deep ocean floor, often containing submarine canyons.

Mid-ocean ridges

Underwater mountain ranges at divergent plate boundaries where new oceanic crust is formed via magma welling up.

Divergent boundaries

Tectonic plates that pull apart, leading to seafloor spreading and mid-ocean ridges.

Convergent boundaries

Plates that collide, causing subduction where dense oceanic crust slides into the mantle, creating trenches.

Transform boundaries

Tectonic plates that grind past one another horizontally, such as the San Andreas Fault.

Magnetic striping

Evidence for seafloor spreading consisting of alternating bands of normal and reversed magnetic polarity.

Coriolis Effect

The deflection of moving water or air caused by Earth's rotation, deflecting to the right in the Northern Hemisphere and the left in the Southern Hemisphere.

Gyres

Large circular current systems that rotate clockwise in the Northern Hemisphere and counter-clockwise in the Southern Hemisphere.

Upwelling

A process driven by wind and the Coriolis effect where surface water is pushed away, allowing deep, cold, nutrient-rich water to rise.

Downwelling

The sinking of surface water that transports oxygen downward but results in lower nutrients at the surface.

Thermohaline Circulation

Density-driven deep ocean circulation controlled by temperature and salinity, also known as the global conveyor belt.

Tsunamis

Long, low, and fast-moving waves caused by earthquakes or volcanic eruptions characterized by a long wavelength and low wave height.

Semidiurnal tides

Common tidal pattern consisting of two high tides and two low tides of approximately equal height per day.

Spring tides

Tides with the greatest tidal range occurring when the Sun and Moon are aligned.

Neap tides

Tides with the smallest tidal range occurring when the Sun and Moon are at right angles.

Oxygen Minimum Zones (OMZ)

Low O2 areas at depth caused by high bacterial respiration and weak circulation.

Photic zone

The upper $200\,m$ of the ocean water column where enough light penetrates for photosynthesis to occur.

Chemosynthesis

The process used by bacteria at hydrothermal vents to produce energy from chemicals like hydrogen sulfide instead of sunlight.

Ocean Acidification

The process of atmospheric $CO_2$ dissolving into the ocean to form carbonic acid, lowering pH and reducing carbonate ions needed for calcification.

Poikilotherms

Organisms that conform their internal temperature to the surrounding environment.

Homeotherms

Organisms like marine mammals and birds that regulate their own internal body temperature.

Countercurrent Heat Exchange (CCHE)

An adaptation where heat from outgoing arterial blood is transferred to incoming venous blood to retain warmth.

Osmoconformers

Invertebrates that conform their internal osmolarity to the environment to lower energy costs.

Osmoregulators

Organisms like bony fish that maintain a constant internal osmolarity regardless of the environment.

Reynolds Number ($Re$)

A ratio of inertial forces to viscous forces; $Re < 1$ means viscous forces dominate (water feels thick), and $Re > 1000$ means inertial forces dominate.

Plankton

Organisms that drift with currents and cannot swim against them.

Phytoplankton

Photosynthetic primary producers that form the base of the marine food web.

Coccolithophores

Nanoplankton characterized by calcium carbonate ($CaCO_3$) scales.

Diatoms

Phytoplankton with silica ($SiO_2$) cell walls called frustules, major producers in upwelling zones.

Dinoflagellates

Phytoplankton with two flagella, some of which are bioluminescent or cause harmful algal blooms (Red Tides).

Holoplankton

Organisms that remain plankton for their entire life cycle, such as copepods.

Meroplankton

Organisms that are only planktonic during their larval stage, such as crab or fish larvae.

Nekton

Active swimmers capable of overcoming ocean currents, such as fish, squid, and whales.

Countershading

A camouflage adaptation with a dark top and light underside that blends in when seen from above or below.

Net Primary Productivity (NPP)

The rate at which energy is stored after respiration, calculated as $NPP = GPP - R$.

Compensation depth

The depth at which the rate of photosynthesis equals the rate of respiration ($P = R$).

Suspension feeders

Organisms that filter food from the water, categorized as active (pumping water) or passive (relying on currents).

Deposit feeders

Organisms that consume organic matter from the sediment.

Bioturbation

The mixing of sediments by organisms while they are feeding or burrowing.

Spartina

Salt-tolerant marsh grasses that stabilize habitats by trapping sediment and protecting against erosion.

Aerenchyma tissue

Specialized air spaces in salt marsh plants that transport oxygen to roots in anoxic mud.

Desiccation

Stress caused when an organism loses water faster than it can replace it, common in the high intertidal zone.

Keystone Species

A species with a disproportionate impact on its ecosystem, such as the $Piaster\,ochraceus$ sea star in rocky intertidal zones.

Trophic Cascade

An ecological phenomenon where predators at high trophic levels affect the abundance of organisms at lower levels (e.g., sea otters protecting kelp by eating urchins).

Zooxanthellae

Symbiotic photosynthetic algae (Symbiodiniaceae) that live inside coral polyps and provide energy.

Bycatch

The unintended capture of non-target species during fishing, such as turtles or dolphins.

Pacific Decadal Oscillation (PDO)

A long-term (decades-long) oceanic temperature shift that influences fish population trends.