Viruses
Which organisms in the marine environment can be infected by marine viruses?
Marine bacteria, plankton, seaweeds, marine plants, and marine animals.
Which group of photosynthetic bacteria is most important in the marine environment?
Cyanobacteria
What ecological role do marine fungi perform in marine ecosystems?
They act as decomposers that break down dead organic matter into detritus.
What are zooxanthellae?
Symbiotic dinoflagellates that live within the tissues of reef corals, sea anemones, and other marine invertebrates.
How do autotrophs and heterotrophs differ in their nutritional energy sources?
Autotrophs manufacture organic compounds from carbon dioxide via photosynthesis or chemosynthesis, whereas heterotrophs derive energy by consuming existing organic matter.
What is a bacteriophage?
A specific type of virus that infects bacteria.
What is the primary role of dissolved organic matter (DOM) in marine food webs?
It serves as a key nutrient and energy source utilized by marine microbes and microbes-consuming organisms.
What is detritus?
Minute particles of decaying organic matter that provide food for marine consumers.
What causes the phenomenon known as a 'red tide'?
Rapid population explosions (blooms) of certain pigmented dinoflagellate species.
What hair-like structures do ciliates use for locomotion and feeding?
Cilia
In what genetic form do retroviruses store their nucleic information?
RNA (ribonucleic acid)
How do chemosynthetic prokaryotes generate cellular energy?
By extracting chemical energy from inorganic chemical compounds rather than sunlight.
Are marine fungi autotrophs or heterotrophs?
Heterotrophs
In what energy storage form do diatoms store excess energy, and how does this affect buoyancy?
They store excess energy as oil (chrysolaminarin/oil), which reduces cell density and helps them stay buoyant in the photic zone.
What chemical compound forms the hard shell (test) of foraminiferans?
Calcium carbonate (CaCO3)
How do lysogenic viruses infect and replicate within host cells?
By inserting their viral DNA directly into the DNA of the host cell.
What are stromatolites?
Massive calcareous mounds formed by layers of cyanobacteria trapping sediment.
Why are fungi classified in their own distinct kingdom rather than as plants or algae?
They lack chloroplasts, cannot photosynthesize, have chitin cell walls, and obtain nutrients exclusively via heterotrophic absorption.
What is the shell of a diatom called, and what material is it composed of?
It is called a frustule, composed of silica (SiO2).
What type of ocean sediment is formed by accumulated shells of foraminiferans and coccolithophorids?
Calcareous sediments (calcareous ooze)
What ecological process occurs when viral lysis affects marine host cells?
Cell bursting releases large quantities of organic matter into the water column as dissolved organic matter (DOM).
How far back does the fossil record for Archaea extend?
Approximately 3.8 billion years.
Where do marine lichens typically live in intertidal environments?
In wave-splashed areas of rocky shores and hard substrates.
How does domoic acid affect higher trophic levels such as marine mammals and humans?
It accumulates in shellfish and small prey fishes, causing severe illness or death when consumed.
What type of seafloor sediment is formed by accumulated skeletons of diatoms and radiolarians?
Siliceous sediments (siliceous ooze)