To answer this question, subtract from the total population of 1000 the homozygous dominant (DD) frogs of 280 and the homozygous recessive (dd) frogs of 220, and you are left with 500 frogs that by default are <span>heterozygotes (dD). The frequency of these frogs would be 500/1000 = 0.5</span>
<span>In order for individuals best suited for growth and reproduction in a particular environment to contribute disproportionately to the next generation natural selection must take place. Natural selection is one of the basic mechanism of evolution. This mechanism leads</span> to adaptations and adaptations contribute to survival and reproduction.
The transpiration pull is just one of the mechanisms that explain the movement or translocation of water in plants, particularly water ascent in tall trees. There is no single exacting explanation as yet for the ascent of water but several theories have been proposed. Of these, the one which has gained wide support is the cohesion-tension theory which recognizes the crucial role of<span> transpiration pull</span><span> as a driving force. These theories are briefly described below.. I dont know maybe this might be helpful</span>
