Answer:
The valves' main job is to keep the blood moving in one direction – back up towards the heart. When the valve is open, blood freely flows upward towards the heart and when the valves are closed, blood cannot flow back
The correct option is this: A STUDY BY DR BIRDIE SHOWED THAT THE NUMBER OF SONGBIRDS IN HER YARD INCREASED DUE TO A MODIFIED FOOD SOURCE.
A scientific claim refers to a claim that is made by a scientist due to the result that he or she obtained in the research that are conducted. In the excerpt given above, it can be seen that Dr Birdie experience influx of songbirds to her yard as a result of the dried apple and the raising that she added to the birds' food.
When the condition is acidic the substance that would leached is d.aluminum which is then the most ample element in the earth. Aluminum becomes a big part of one's life. It can be use in one's daily life like a beer can, cables,etc.
If we had no cilia in our trachea, our lungs would be filled with dust and microorganisms that we breathe in.
