D
Explanation:
With the help T cells , B cells make special proteins called antibodies which stick to antigens on surface of germs stopping them in their track.
Fossil fuels and green house gases which burn holes in the ozone layer of the atmosphere causing global warming
Answer:
Hydrogen atom of one molecule and carbon atom SPF another molecule
Answer:
Yes
Explanation:
No matter what age, trees still give out oxygen. It may not be the same amount as an older tree, but it still has the same effect.
Hydropower can be harnessed from flowing and falling water. Water stored behind dams and at a height has a lot of potential energy which is converted into mechanical and electrical energy.This water is released gradually and is made to fall under the force of gravity and drive hydraulic turbines and electrical generators.
Hydropower is also another indirect form of using solar energy. Hydropower has great potential as a supplier of electricity but environmental constraints limit such a development as the generation of electricity by hydroelectric power plants result in pollution and massive ecological disruptions such as land flooding, siltation, eutrophication and adverse effects on flora and fauna.
Smaller dams and reservoirs cause less damage but cannot exploit the full potential of this energy resource. Planning environmental impact assessment and construction of a hydroelectric power plant takes many years and the high initial capital investments are also limiting factors in the development of hydropower.
The development cost of hydroelectric power plants can be reduced by developing low cost turbines and generators, involving public participation in the development and operation of the project and using efficient environmental friendly technologies.
