A. social age
b. chronological age
c. psychological age
<span>d. biological age
Its D, biological age.</span>
<span>All cells have the same DNA. They are different because different genes have been locked up and only some of them are expressed. The process began in the embryonic stage, when stem cells are turned into different types of cells by turning off some of the genes. Scientists have been looking for ways to reverse the process, meaning turning specialized cells back into stem cells. Some success has been reported using different methods. The latest one uses a weak acid to stress the cells.</span>
The answer I think is the environment for this one. <span />
From periodic table carbon have six electrons nitrogen has seven electrons while oxygen has eight electrons. it s electronic configuration for carbon is 2.4, for nitrogen is 2.5 while that for oxygen is 2.6. Their dot diagram are as follows
Exchange of gases in fish is very efficient because of: the large surface area of the gills. the large surface area of the blood capillaries in each gill filament. the short distance required for diffusion – the outer layer of the gill filaments and the capillary walls are just one cell thick.
