Useful traits have been accumulated in plants and animals over the centuries by how plants have undergone through certain phases, specifically called selection. Most of these traits are accumulated naturally but others may be acquired in the opposite way through man-made cultivation. Hope this answers your question.
Photosynthesis<span> makes the glucose that is used in </span>cellular respiration<span> to make ATP. The glucose is then turned back into carbon dioxide, which is used in </span>photosynthesis<span>. While water is broken down to form oxygen during </span>photosynthesis<span>, in </span>cellular respiration<span> oxygen is combined with hydrogen to form water.
~hope that helps</span>
<span>Natural selection is likely when there are stronger selection pressures. For example, a perpetual selection pressure is the fact that organisms have to compete for food and resources, meaning the best adapted ones survive. However, a stronger selection pressure may cause natural selection to occur more obviously. An example of this is when the number of white peppered moths decreased during industrialization in England due to the soot collecting on the trees. The change in population was very fast and obvious.</span>
I think it’s organism since it already stated skeletal and respiratory then it means it cannot be tissue or organ because skeletal is included so i say go for organism
