exam4 oceanography

What is the major difference between prokaryotes and eukaryotes?

Eukaryotes have membrane-bound nuclei and organelles

Which organelle evolved from a captured prokaryote?

Mitochondrion

What organelle is responsible for photosynthesis in eukaryotes?

Chloroplast

Where did the chloroplast in all photosynthetic eukaryotes originate?

A cyanobacterium

Which organisms photosynthesize without a chloroplast?

Cyanobacteria

What process uses CO₂ and sunlight to produce carbohydrates and oxygen?

Photosynthesis

What process uses chemicals like H₂S instead of sunlight to make food?

Chemosynthesis

What is the waste byproduct of photosynthesis?

Oxygen

Which type of organism makes its own food?

Autotroph

Which group includes consumers that must ingest other organisms?

Heterotrophs

What are phytoplankton?

Microscopic autotrophs that form the base of ocean food chains

Why are phytoplankton considered highly productive?

They have high turnover and photosynthesize rapidly

Where does most oceanic photosynthesis occur?

In the surface layer where light and nutrients are available

What limits productivity in the open ocean?

Lack of nutrients

Where is marine productivity highest?

In coastal areas and zones of upwelling

What do seaweeds (multicellular algae) contribute to the ocean?

They are autotrophs that support benthic food webs

which level has the greatest biomass?

In a trophic pyramid

Why does each step up the trophic pyramid contain less energy?

Energy is lost as heat and waste at each level

What are primary consumers?

Herbivores that eat producers

What is an example of a secondary consumer?

A fish that eats zooplankton

What does "ecological tolerance" mean?

The range of conditions an organism can survive in

What physical factor determines the depth of photosynthesis?

Light availability

Which zone receives enough light for net photosynthesis?

Euphotic zone

Which ocean zone has light but not enough for photosynthesis?

Disphotic zone

Which ocean zone has no light?

Aphotic zone

What happens in a hypertonic solution?

Water moves out of the cell

What happens in a hypotonic solution?

Water moves into the cell

What is osmosis?

The movement of water across a membrane from low to high solute concentration

Which nutrients are most limiting to phytoplankton?

Nitrogen and phosphorus

What is an organism’s niche?

Its role in the environment

What is the correct order of ecological organization from smallest to largest?

Individual, population,community,ecosystems

Where are pelagic organisms found?

In open water away from the ocean bottom

What is the neritic zone?

Near shore Coastal waters over the continental shelf

What zone includes deep open ocean beyond the shelf?

Oceanic zone

Which marine organisms drift with currents?

Plankton

Which marine organisms can swim actively?

Nekton

What are benthic organisms?

Organisms that live on or in the seafloor

What is the littoral zone?

The intertidal zone between high and low tide

Which zone is deepest in the ocean?

Hadal zone

What is endosymbiosis?

When one organism lives inside another

What did red and green algae evolve from?

Separate endosymbiotic events

What type of algae gave rise to land plants?

Green algae (Chlorophytes)

What are phytoplankton?

Microscopic autotrophs that form the base of ocean food webs

What are picoplankton?

Tiny phytoplankton

Why are algae not one natural group?

They evolved separately and are not all related

What is the main cell covering of diatoms?

Silica

What causes harmful algal blooms like red tides?

Dinoflagellates

What do coccolithophores produce?

Calcium carbonate (limestone) shells

Which group of algae helped form chalk and white cliffs?

Coccolithophores

What type of algae is multicellular and planktonic?

Sargassum

Why does phytoplankton productivity vary?

Nutrients and mixing conditions vary by location

What is a major cause of oceanic dead zones?

Nutrient runoff leading to algal overgrowth

What are zooplankton?

Heterotrophs that eat phytoplankton or other small organisms

What are foraminifera shells made of?

Calcium carbonate (CaCO₃)

What are radiolarians made of?

Silica

What type of animals are copepods

krill

What are meroplankton?

Organisms that are planktonic only in their larval stage

What large

weakly swimming zooplankton drift in currents?

What is a defining trait of nekton?

Active swimming ability

Which mollusks are part of the nekton?

Squid and nautilus (cephalopods)

Which group includes the most marine vertebrates?

Bony fishes (Osteichthyes)

Which fish has the largest body?

Ocean sunfish

Which fish is the longest?

Oarfish

What are examples of the most abundant small schooling fish?

Herring

What is the largest fish species?

Whale shark

What makes penguins unique among marine birds?

They are flightless and live mostly in the Southern Hemisphere

Where do sea turtles return to lay eggs?

On the beaches where they were born

What is the main salt-removal adaptation in sea turtles?

Salt glands that excrete excess salt

Which marine mammals include baleen and toothed species?

Cetaceans (whales

Which ocean resource is the most valuable in terms of economic worth?

Petroleum (oil and gas)

What is a key environmental risk associated with bottom trawling?

Destruction of benthic habitats

Why is deep-sea mining controversial?

It disturbs seafloor ecosystems and is difficult to regulate

What does "non-renewable" mean in terms of ocean resources?

Cannot be replenished on human timescales

Which ocean resource is considered renewable?

Tidal energy

What is a common use of evaporites from the ocean?

Table salt and gypsum production

What is a major issue with desalination?

It produces brine waste and is energy-intensive

Methane hydrate (clathrate) is found in which form?

Frozen gas trapped in ice under the seafloor

What causes petroleum to migrate through rock layers?

Pressure

What is "diagenesis" in petroleum formation?

Breakdown of organic matter into hydrocarbons

Which country is known for anchoveta harvests and fishmeal production?

Peru

What ocean condition promotes anchovy populations off Peru?

Upwelling during La Niña

What causes fish populations to crash during El Niño events?

Collapse of nutrient-rich upwelling

What is the maximum sustainable yield?

The largest harvest that does not reduce future population

What is a major issue with overfishing predatory species?

It disrupts entire marine food webs

What is bycatch?

Unintended capture of non-target species

What fishing method causes the most habitat damage?

Bottom trawling

How is aquaculture different from wild capture?

It farms species in controlled environments

Which fish is a major example of aquaculture production?

Carp

What is multi-trophic aquaculture?

Farming multiple species that recycle each other's waste

Why is algin harvested from marine algae?

It is used as a thickener in food and cosmetics

Which marine organism is a growing source of new medicines?

Tunicates and deep-sea microbes

Which non-extractive use of the ocean is increasing rapidly?

Shipping and recreation

What is a downside of using dispersants in oil spill cleanup?

They may increase toxicity in deeper waters

Which pollutants bioaccumulate in top predators?

DDT

What is eutrophication?

Over-fertilization of water causing dead zones

Why are estuaries especially vulnerable to pollution?

They receive runoff from both land and sea

What causes microplastic buildup in ocean gyres?

Circulating currents that trap floating debris

How do greenhouse gases affect Earth’s climate?

They trap longwave heat radiation from Earth

Which gas is the primary contributor to ocean acidification?

Carbon dioxide (CO₂)