Plankton Test Flashcards
(57 cards)
The tiny plant like organism which causes red tide is called a?
Dinoflagellates
What is the purpose of the flagella on dinoflagellates?
Spins cell around
Propels it through water
When are blooms created that release toxin into the water?
When certain dinoflagellates are in higher than normal concentrations
In Florida waters, what is the scientific name for the most common red tide dinoflagellates?
Karenia brevis
How do dinoflagellates reproduce?
Cell division
How often do dinoflagellates reproduce?
Every 48-120 hours
What 4 factors influence the growth of K. brevis?
- sunlight
- temperature
- salinity
- amount/type of nutrients available in the water
What 2 factors play a role in determining when and where blooms will occur?
- winds
- currents
When can K. brevis blooms be a problem for people?
When winds and currents drive the blooms close to shore, where they can be concentrated
Why do researchers off the coast of Florida believe that red tide blooms are not related to pollution?
Red tide blooms have happened for hundreds of years, long before man-made pollution became prevalent
K. brevis red tide blooms occur most frequently between what months of the year?
August-February
How do K. brevis toxins affect fishes?
Paralyzes the nerves of the fish causing death by suffocation
What is the greatest threat to humans posed by K. brevis red tides?
Consumption of bivalve shellfish that have been contaminated with red tide toxins
If humans consume clams, mussels, oysters, or coquinas, that have been contaminated with the red tide toxin what can happen to them?
They can become ill with Neurotoxic Shellfish Poisoning
What are some symptoms of Neurotoxic Shellfish Poisoning?
Nausea, diarrhea, tingling of fingers and toes, reversal of sensations (hot seems cold, cold seems hot)
In humans, how long does it usually take for the symptoms of NSP to occur?
Few minutes to several hours
What does the Florida Department of Environmental Protection do when beds are threatened by red tide blooms?
Closes harvesting areas
Besides poisoning, how else can people be affected during red tide blooms?
Sneezing, coughing, general respiratory irritation
List the four reasons why it would be extremely difficult and costly to get rid of a red tide?
- red tide blooms occur over hundreds to thousands of square miles
- distributed throughout the water column
- can be moved great distances along the coast
- fluctuate daily with tides
Why are chemical and biological control agents not a practical alternative to control and disperse the red tide blooms?
May adversely affect other forms of marine life
What technology is being used today to detect and track the movement of ocean currents and blooms?
Satellites
What does the term plankton mean?
Float or drift in ocean
2 main types of plankton?
Zooplankton and phytoplankton
Why must phytoplankton remain in the photic zone?
They need sunlight to make food for themselves
