DNA can be transferred naturally between species by breeding.
<span>Euglena is autotrophic and has a chloroplast. Euglena can photosynthesize and make its own food.
Zooflagellates cannot photosynthesize and cannot make their own food. So, Euglena is considered phytoplankton and Zooflagellates are considered zooplankton.</span>
Example: when we exercise, breathing and blood circulation must increase to meet the demand of our cells to get rid of carbon dioxide and let in oxygen.
