Rapid overgrowth of cyanobacteria may occur due to
Increased nutrient content
Lower pH
Higher temperatures
A reduction in competition and predation
Nutrient exhaustion is associated with rapid death and decline, forming scum
The existence of cyanobacterial blooms are not related to climate change
What are the long-term consequences of cyanobacterial overgrowth?
Increase in climate
Food web disruption
Decrease in biodiversity
Economic losses
What of the following nutrients are associated with cyanobacterial blooms?
Magnesium
Iron
Phosphate
Carbon
Which eukaryotic species overgrowth causes 'red tide'?
Microcystis aeruginosa
Karena brevis
Trichodesmium
Prochlorococcus marinus
How may a Harmful Algal Bloom cause indirect toxicity to organisms?
Generating a hypoxic or anoxic environment
Producing waste products
Increasing competition for resources
Releasing toxins
Microcystis aeruginosa and Trichodesmium are both eukaryotic organisms
People boating on high risk lakes reported symptoms of toxicity how much more/less frequently than others? (Approximately)
Three times as much
Twice as much
Half as much
No difference
Microcystis aeruginosa is a gram-negative species of bacteria
Microcystins enhance fluid uptake in fish causing increased toxicity which can lead to liver damage or cancer
What are the effects caused by a bloom of Microcystis aeruginosa?
Nutrient content of water is increased
Selective predation occurs whereby the food web is disrupted
Water quality is decreased
Economic losses due to lack of fishing and tourism
Microcystis aeruginosa is made up of spherical cells, a flagellum and a gram-negative wall structure
What size is the genome of Microcystis aeruginosa? (Approximately)
6 Mb
4 Mb
5 Mb
2 Mb
Which of the following statements are true regarding gas vesicles in Microcystis aeruginosa?
They are produced during the night to bring the cell to the surface of the water
They are arranged in a pentagonal array
They reduce the surface area: cytoplasm ratio
They provide buoyancy for access to light
What are the names of the gas vesicle structural proteins?
GpB2, GpB3 and F270
SI3P and NNt3
P2f and Fn73
GvpA and GvpC
A cork and hammer experiment was conducted to mimic the effect of vesicle disruption due to sudden pressure change
Which of the following statements are true concerning algicides?
Their use is not feasible on a large scale
Algicide use is ineffective at destroying cyanobacterial blooms
Bacterial toxins may be released when the cells are destroyed during algicide treatment
None of the above are true
Sonication or hydrostatic pressure may be used as control measures for treating algal blooms as this has an effect on the buoyancy of gas vesicles
Which of the following are appropriate control measures in regards to cyanobacterial blooms?
Increase mixing/flushing
Use of micropredators
Limit temperatures
Use of algicides
Which of the following statements about Microcystin-LR is false?
Peptide synthesis is non-ribosomal
Preferential uptake by liver transporter OATP
Released on lysis of cells
Cyclic hexapeptide
How does microcystin-LR cause liver damage?
Inhibits protein PP2A
Causes damage due to reactive oxygen species and apoptosis
Inhibits protein phosphatase-1
Is transported by protein OAFP
During the day, what genes are transcribed by MIcrocystis aeruginosa?
Energy metabolism
Photosynthesis
DNA repair
DNA replication
During the night, what genes are transcribed by Microcystis aeruginosa?
Eutrophicaton due to hippo waste occurred in Kruger National Park, causing many unexpected animal deaths
The addition of chlorine to treat water in Brazil meant less people were affected by the HAB toxins
Microcystin-LR was produced by Microcystis bloom in Tabocas reservoir causing contaminated water to be distributed in Brazil
What serious health outcomes are associated with long-term exposure to cyanobacterial blooms?
Alzheimer's disease
Liver cancer
Emphysema
Parkinson's disease
