Phytoplankton Flashcards
(16 cards)
What are the major differences between prokaryotes and eukaryotes in terms of ribosomes and genetic material?
Prokaryotes possess 70S ribosomes and circular DNA in the cytoplasm, while eukaryotes have 80S ribosomes and DNA as chromosomes in the nucleus
Name the five groups of phytoplankton and one trait
Cyanobaceteria - nitrogen fixation
Coccolithophoras - CaCO3 shells
Diatoms - silicate shells
Dinoflagellata - mixotroph
Green Algea - ancestors of land plants
Why are some microorganisms referred to as “hidden players”?
Many microorganisms are difficult to culture and study, leading to limited knowledge of their ecology and physiology.
What are the functions of flow cytometers in phytoplankton research?
Flow cytometers use lasers to examine and sort cells, helping to reveal hidden diversity at small size classes
What is the difference between Synechococcus and Prochlorococcus, and where are they most abundant?
Synechococcus is more abundant in nutrient-rich environments, while Prochlorococcus dominates in nutrient-poor regions and is the most abundant picophytoplankton.
What is the PI curve in relation to phytoplankton?
The PI curve (photosynthesis-irradiance curve) shows the relationship between photosynthetic rate and light intensity, helping to understand light-use efficiency
Explain the importance of the microbial loop for the marine ecosystem.
The microbial loop describes the role of phytoplankton, bacteria, and protists in recycling nutrients and organic matter, integrating bacteria into the food web.
How does a viral shunt differ from a viral shuttle?
The viral shunt releases nutrients as dissolved organic matter, while the viral shuttle contributes to carbon export.
Describe the three main types of viral life cycles
Lytic cycle: Destroys the host cell, releasing viruses.
Lysogenic cycle: Integrates the viral genome into the host genome.
Budding: Slowly releases virus particles without killing the host cell.
What is the impact of climate change on the microbial loop?
Climate change affects the microbial loop by altering sea temperatures, increasing stratification, and causing nutrient scarcity, impacting microbial community structure and function.
What is phytoplankton?
Unicellular microorganisms that perform photosynthesis and form the base of the marine food web.
What are prokaryotes?
Microorganisms without a nucleus, such as bacteria and archaea
What is a PI curve?
A graph showing the relationship between light intensity and photosynthetic rate
What is the microbial loop?
Bacteria that consume organic matter.
What is the viral shunt?
The process where viruses release DOM by infecting and lysing cells.
What is metabarcoding?
A DNA-based technique to analyze species composition in environmental samples.
