The flow of energy from one level to another does not happen with 100% efficiency. The producers only transfer 10% of the energy they absorb from the Sun. The major chunk of the absorbed energy goes into the growth of the producers, the rest gets lost in the form of waste (shedding of leaves, reproduction, etc.) and the remaining 10% is the amount that is available to the primary consumers. So by this logic, if there is 150,000 KJ of energy available at the producer level, then, only 15,000 KJ of energy will get transferred to the primary consumers.
 
        
             
        
        
        
The answer is light.
One of the factors that affect photosynthesis is light. Without light, the photosynthetic rate is reduced or even stopped which consequently affect algal growth. With increasing depth in the ocean, there is less sunlight present. Still, a<span>lgae have accessory photosynthetic plastids other than the chloroplasts</span><span> that can absorb different light in greater ocean depths. This helps them to maximum use sunlight in such conditions. But, in the end, at some particular depth, they would not be able to survive.</span>
        
             
        
        
        
<span>Answer:
Macrophages- WBC that combat multi-cellular parasites.
Neutrophils- most abundant type of WBC which identifies and produces antibodies.</span>
        
             
        
        
        
Three reasons a species could become extinct include, deforestation, being overhunted, not enough food available.