The reason why there is a green layer of algae was because
of the reason that there may be too much fertilizer applied in the lawn. When
having too much fertilizer, and it had been rained down—there could have been a
possibility of run-off to be flown down on the lawn of which has been sloped
and made its way on the pond. By this, it increases the nutrients in the pond,
making the algae to grow on it.
 
        
                    
             
        
        
        
Answer: The correct answer to the question is option WHEN GLUCOSE LEVELS ARE LOW AND LACTOSE IS PRESENT.
Explanation: To start with,Lac operon can be simply defined as a part of the DNA that is under the part of the DNA is manipulated and controlled by the same promoter,they can be found in some prokaryotic cells giving room for regulation over excess synthesis of protein.so simply put,these specific segment of the DNA binds with the segment of the polymerase of RNA so that transcription of the mRNA from the operon genes will be achieved. 
Lac operon is also known as lactose operon, it is seen in some enteric bacteria like e.coli where they play a crucial role in coding of genes for those proteins that function in moving lactose into the cystocel and digesting it to form glucose that is used for energy generation. These lac operon are are most active when glucose levels are low and lactose is present,with the low level of glucose, the lac operon can be transcribed to a high level,this is to ascertain that the bacteria only gets to activate the lac operon and can only make use of it,that is using lactose when all the preferred energy source from glucose has been exhausted.
 
        
             
        
        
        
Testosterone is the principal male sex hormone.
        
             
        
        
        
It is called haemogloblin.
        
             
        
        
        
When an individual is dehydrated, his or her intravenous fluids should be isotonic, because either a hypertonic or hypotonic IV would both cause damage to the individual’s red blood cells. Isotonic solutions are used: to increase the EXTRACELLULAR fluid volume because of blood loss, surgery, dehydration, fluid loss that has been loss extracellularly.