ANSWERS
What is the estimated number of fungal species on the planet?
ranges from 1.5 to over 5 million, with less than 10% identified.
What are the characteristics of fungi?
eukaryotes, mostly multicellular, decomposers, and have cell walls
made of chitin.
How many marine fungal species have been retrieved exclusively from
the marine environment?
Approximately 1,100
What are the two types of marine fungi based on their habitat
restrictions?
obligate (restricted to oceanic habitats) or facultative (able to grow in
marine environments as an extension of their normal range).
What role do fungi play in the marine biosphere?
heterotrophic, primarily saprophytes, and interact with algae,
prokaryotes, plants, and animals, contributing to nutrient cycling.
Saprophyte
a plant, fungus, or microorganism that lives on dead or decaying organic
matter.
,What is the significance of extracellular enzyme activities in fungi?
Fungi secrete enzymes that break down compounds in their
environment, including industrial toxins and crude oil components.
What is a notable ability of fungi regarding environmental pollutants?
Fungi have the ability to degrade hydrocarbons and marine plastic
waste, such as polyethylene.
What types of compounds do marine fungi produce?
antibacterial, antiviral, and antiprotozoal compounds.
WHat are some beneficial symbionts of fungi
associated with green algae and offers protection from dehydration
during low tides, associated with salt-marsh plants assisting plant to
obtain nutrients
Describe the marine fungal life cycle
produce zoospores that encyst and form a germ tube, leading to the
development of a sporangium that releases new zoospores.
What is the mycoloop?
Chytrids can transfer material from large inedible phytoplankton to
zooplankton and can influence the edibility of phytoplankton colonies.
How do fungi contribute to the marine carbon cycle?
processing phytoplankton-derived organic matter.
What is the most abundant biological entity in the sea?
Viruses, with about 10 million per teaspoon of seawater.
What types of viruses are found in marine environments?
, bacteriophages (infecting bacteria), cyanophages (infecting
cyanobacteria), and viruses that infect archaea and eukaryotic
phytoplankton.
What are the structural components of viruses?
nucleic acid (either DNA or RNA) surrounded by a capsid and have no
ribosomes, meaning they cannot make their own proteins.
What is the structure of dsDNA viruses?
head (nucleocapsid) connected to a
tail structure used for adsorption
to the cell and injection of the
nucleic acid into the host cell. they are the best phages and consistof
Myoviruses, podoviruses, and siphoviruses
What are Myoviruses?
the most commonly isolated phages from natural communities,
characterized by a broad host range and a contractile tail.
What distinguishes Podoviruses from other phages?
they are less common and have a narrow host range.
What are Siphoviruses known for?
they are frequently isolated from seawater, have a broad host range,
can integrate into the host genome, and possess a long flexible tail.
How do we identify viruses in marine environments?
morphology by filtering seawater, staining with heavy metals, and
imaging using transmission electron microscopy (TEM) or
epifluorescence microscopy with DNA/RNA stains.