1 Coelomate animals or Coelomata (also known as eucoelomates â true coelom) have a fluid filled body cavity called a coelom /ËsiËlÉm/ with a complete lining called peritoneum derived from mesoderm (one of the three primary tissue layers).he coelom allows muscles to grow independently of the body wall â this feature can be seen in the digestive tract of tardigrades (also known as water bears) which is suspended within the body in the mesentery derived from a mesoderm-lined coelom.
At a 3 percent growth rate, its doubling time â or the number of years to double in size â is 23 years. (The doubling time for a population can be roughly determined by dividing the current growth rate into the number 69. Therefore, 69/3=23 years. Of course, if a population's growth rate does not remain at this rate, the projected doubling time would need to be recalculated.)
has doubled in 40 years from 1959 (3 billion) to 1999 (6 billion) is currently (2017) growing at a rate of around 1.11 % per year. growth rate reached its peak in the late 1960s, when it was at 2%. growth rate is currently declining and is projected to continue to decline in the coming years.