OCNG EXAM 3

What makes something alive?

It should reproduce, consume energy, have membranes, an internal solvent(water), and respond/adapt to stimuli/the environment.

Know the Linneus classification system, incl. 3 domains of Life

The Linneus classification is Kingdom Phylum Class Order Family Genus Species. The 3 domains of life are bacteria, archaea, and eukaryota.

Plankton vs nekton vs benthos - what are those? examples of each?

Plankton drifts/floats on the currents (such as phytoplankton). Nekton can control where it swims (sharks). Benthos are bottom-dwelling (like starfish).

Land vs sea, water column vs benthos - where is there more diversity, and why?

There are more species within land and water column, because there are more varied habitats.

SA:V - you best know what that means

I do! Surface Area:Volume ratio. The higher SA:V, the more resistant to sinking.

Living in the ocean is different than living on land - what are some ways organisms are adapted to living in water? Much of the chapter is focused on this.

Streamlining, broadcast spawning (how fish reproduce), counter shading.

Know the regions of the water column, and basic characteristics (physical, maybe chemical)

epipelagic (sunlit), mesopelagic (twilight), bathypelagic (midnight), abyssopelagic (abyssal), and hadalpelagic (hadal) zones. The water column's basic characteristics involve its physical (temperature, salinity, light), chemical (oxygen, nutrients, pH), and biological (plankton, fish) properties

What are ways we measure primary productivity?

tracking the amount of carbon dioxide consumed or oxygen produced during photosynthesis, and by measuring the net biomass created by an ecosystem. Specific methods include the light-dark bottle technique for aquatic systems, which measures oxygen changes

Different kinds of primary productivity? How do they differ?

Gross Primary Productivity (GPP) and Net Primary Productivity (NPP). GPP is the total amount of energy captured by producers through photosynthesis, while NPP is the energy that remains after the producers use some of that energy for their own respiration.

Know the factors that affect rates of photosynthesis and how they affect it.

light intensity, carbon dioxide concentration, and temperature.Increasing light or CO2 increases the rate until another factor becomes limiting, while temperature must be within an optimal range because enzymes involved can denature at high temperatures or be too slow at low temperatures.

We talked about four major groups of phytoplankton, you should know them.

Zooplankton, phytoplankton, bacterioplankton, virioplankton

What is the biological pump? Be able to explain it.

phytoplankton perform photosynthesis at the surface, and then carbon-rich organic matter sinks to the deep sea as "marine snow" This carbon-rich organic matter is then eaten in a process called remineralization.

Know what a trophic level is and how that relates to food chains and webs.

the position an organism occupies in a food chain or food web, representing its feeding relationship to other organisms

We talked about fisheries science a bunch, plus read a great article about overfishing - know these topics.

Fisheries resources are mostly from continental shelves and upwelling. Standing stock is the mass present in an ecosystem at a given time. Bycatch is organisms caught accidentally with the target system. Due to overfishing, fisheries nowadays are fishing in deeper waters where fish repopulate slowly.

What are different ways animals stay afloat in the oceans?

gas container, swim bladder.

Zooplankton - what are they, what are the major groups, and why are they important?

Zooplankton are ‘animal plankton’ and can be macroscopic or microscopic. They help remove carbon from the atmosphere and are an important part of the food web.

What are all those fins on a fish for? How does lifestyle influence the shape of fins that have evolved for different fish?

Locomotion, steering, stability. Prey fish tend to have rounded and forked caudal fins. Predator fish have lunate, truncate, and heterocercal (sharks)

Why do deep-sea fish look the way they do?

They have adapted to their environment. Big jaws allow them to capture whatever prey they find, and the big eyes are used to identify differences in light, etc.

Why do fish form schools, and how do they do it?

Protection from predators. Fish school by using a combination of visual cues and their lateral line, which senses water pressure changes, to coordinate their movements with their neighbors.

What are the major groups of marine mammals?

Carnivora(walrus, sea lion), cetacea(whales, dolphin), sirenia(dugongs)

What adaptations do whales have for living as air-breathing animals in the ocean realm?

Blowhole, streamlined body.

Difference between baleen and toothed whales?

Baleen whales feed on plankton by filtering water using their baleen. Toothed whales catch their prey, like giant squid.

Different groups of mysticeti - who are they and how do they make a living?

Grey whales: bottom feeders. Rorquals: Skim feeding, slowly filtering nutrient dense water. Right whales: Gulp feeding, taking gulps of water and then filtering.

Coral reefs! what are they? why are they important? where do we find them?

Underwater ecosystems built by marine polyps. Important for marine biodiversity, coastal protection. Found in warm, shallow tropical and subtropical oceans.

what are zooxanthellae? and what about those crustose coralline algae? and what types of seafloor do corals like to live on?

Zooxanthellae are microscopic algae that live in a symbiotic relationship with corals, providing them with energy through photosynthesis in exchange for a protected environment. Crustose coralline algae are a type of red algae that forms hard, crust-like layers on the seafloor, helping to cement coral reefs together. Corals live on hard substrates, like rock or skeletons.

what are corals in trouble nowadays? explain ocean acidification in relation to corals, why global warming is bad for corals, if they like lots or little nutrients, and what happens when the opposite occurs.

As the ocean absorbs excess carbon dioxide, it becomes more acidic affecting corals which are made of calcium carbonate. Global warming leads to coral bleaching. Corals like low nutrient levels, the opposite leads to algal overgrowth.

vents! what is a symbiosis? what kinds of metabolisms do the symbiotic microbes have? are there other places where one finds symbioses?

A symbiosis is a close, prolonged relationship between two creatures. Symbiotic microbes in vents use chemosynthesis, though there are also sulfur-oxidizing and methane-oxidizing bacteria. Symbioses can be found on land or in the ocean.

be able to name a vent animal specific to the east Pacific, the west Pacific, and the Atlantic Ocean.

East Pacific: giant tube worm. West Pacific: Alviniconcha. Atlantic Ocean: Bathymodiolus.

know what a feedback loop is and how to define which way it's going.

A feedback loop is a process where the output of a system is circled back and used as an input, either amplifying change (positive feedback) or dampening it (negative feedback)

what are 6 ways we study past climate - how does each way work (generally)?

Seafloor sediments, coral deposits, glacial ice, tree rings, pollen, historical documents.

we discussed four natural causes of climate variation - what are they?

solar energy changes, variation of Earth’s orbit, volcanic eruption, plate tectonics

when was it hotter than it currently is? and if it was once hotter, why are we worried about current warming trends?

The rate of current warming is 5000 times faster than anything before. Paleocene-Eocene Thermal Maximum.

what is the international group that studies climate change and summarizes scientific literature called?

IPCC

how does the greenhouse effect work, and what are the main gasses we are concerned about?

CH4, CO2, CFC. Greenhouse effect – keeps Earth’s surface habitable. Incoming heat energy is shorter wavelengths, Longer wavelengths – some trapped, some escape, net warming effect.

you best know what Keeling is in reference to, and why it is important.

Keeling Curve - longest continued record of CO2 measurements.

when was the PETM and what is it? why study it?

Paleocene-Eocene Thermal Maximum. 56 million years ago, huge release of CO2 and methane. Study it for future climate effects.

what are current predictions for warming trends by the year 2100? some evidence supporting those predictions?

predicted sea level rise by 2100 is 0.28-1.31 m. 1.9-4 C increase.

we spent a lot of time talking about what is predicted to happen as a result of rising temperatures - know these impacts and why they matter

heat waves, droughts, and wildfires, lead to sea level rise from melting glaciers, impact human health, alter ecosystems, and threaten food and water supplies. they lead to property damage, costly economic disruptions, damage to natural habitats, and pose direct threats to human life, health, and livelihood.

ocean acidification again - know what it is and how it related to climate change

Ocean acidification is the ongoing decrease in the pH of the Earth's oceans, caused by the ocean's absorption of excess carbon dioxide from the atmosphere. This is directly linked to climate change, as human activities like burning fossil fuels release large amounts of CO2.

Why is the impact of oil spills difficult to mitigate?

Oil spills are hard to mitigate because oil changes properties (weathering), spreads rapidly due to wind/currents, gets trapped in sensitive habitats (marshes, coral reefs), and cleanup methods (booms, dispersants, burning) have limitations, often failing to remove all oil or causing secondary damage, leading to long-term ecological harm. 

What were some changes made after the Exxon Valdez spill

mandating double-hulled tankers, increasing spill prevention/response funding, requiring better contingency plans, and establishing citizen oversight

How do we cleanup oil spills?

Cleaning up oil spills involves a multi-pronged approach using containment (booms), removal (skimmers, vacuums, manual labor, sorbents), chemical treatment (dispersants, bioremediation), and sometimes controlled burning, with the best method depending on oil type, weather, and location, often starting with containing the slick before tackling shores or open water. 

Explain eutrophication and how it relates to hypoxia/dead zones

Eutrophication is the over-enrichment of water with nutrients (nitrogen, phosphorus) from sources like fertilizer/sewage, triggering massive algal blooms; when these algae die and decompose, bacteria consume large amounts of oxygen, creating hypoxic (low-oxygen) or "dead" zones where most marine life can't survive, leading to fish kills and ecosystem collapse.

Explain bioaccumulation and biomagnification.

Bioaccumulation is the buildup of toxins in a single organism over its lifetime, while biomagnification is the increasing concentration of those toxins as they move up successive trophic levels in a food chain, making top predators most vulnerable to harmful levels.

Can you give an example of biomagnification of a toxin that was discovered and then addressed to mitigate the impact of the toxin on humans or other animals?

iDDT was shown to cause thin shells in bird eggs, nearly leading to the extinction of the peregrine falcon and bald eagle.