Marine Bio Quiz 1

Phytoplankton

microscopic, plant-like organisms (mostly single-celled algae and bacteria) that drift in the sunlit upper layers of freshwater and marine ecosystems

Zooplankton

tiny, heterotrophic aquatic animals and microorganisms that drift in marine and freshwater water columns

Holoplankton

aquatic organisms that spend their entire life cycle—from birth to death—as plankton

Meroplankton

organisms that spend a portion of their life cycle as plankton in the water column before settling to the seafloor or becoming active swimmers (nekton) as adults

Dinoflagellates

a large group of mostly marine, single-celled protists known for having two flagella. They play a critical role in oxygen productio, and the food web

Flagella

long, hair-like appendages that protrude from the cell body. They act as microscopic propellers

Diatoms

a large group of single-celled algae with unique silica shells. They play a crucial role in oxygen production and the food chain

Nekton

aquatic animals that swim freely and independently of water currents. Primarily composed of fish and mammals

Benthos

organisms, like animals and plants, that live on, in, or near the bottom of aquatic environments

Deep Scattering Layer

a region in the water column where there is a high density of marine organisms that reflect sound.

Primary productivity

the rate at which energy is converted by photosynthetic autotrophs to organic substances, measured in biomass

Photosynthesis

the process by which green plants, algae, and some bacteria convert light energy into chemical energy

Biomass

organic, renewable material derived from plants, animals, and microorganisms, that can be used to generate energy

Chlorophyll

a natural green pigment essential for plants to convert sunlight into energy

Photic Zone

the top layer of the ocean, extending from the surface to where sunlight enables photosynthesis

Harmful Algal Bloom (HAB)

a rapid, excessive growth of algae or cyanobacteria in water that produces dangerous toxins or depletes oxygen

Limiting Factor

any biotic or abiotic resource, such as food, space, or temperature, that restricts the size, growth, or distribution of a population within an ecosystem

Biomagnification

the increasing concentration of toxic, persistent substances, such as heavy metals or pesticides, in the tissues of organisms at each higher trophic level in a food chain

Producer

an organism that forms the base of every food chain and ecosystem, providing the essential energy needed for all other living things

Consumer

an organism that cannot produce its own energy and obtains its nutrients and energy by eating other organisms

Decomposer

an organism that breaks down dead or decaying organic material to obtain energy

Trophic Level

the specific position an organism occupies in a food chain, determined by its feeding mode and how removed it is from the energy producers

Trophic Cascade

an ecological phenomenon where the addition or removal of top predators triggers indirect changes in the populations of prey, herbivores, and plants across lower food web levels

Food Web

a complex, interconnected network of multiple food chains that illustrates the flow of energy and nutrients within an ecosystem

Organsim classification system levels

Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species