So that all animals can be classified and accounted for. This is also used in dichotomy analysis in order to find out the species of an invasive plant or animal
Answer:
In heart valve disease, one or more of the valves in your heart doesn't work properly. Your heart has four valves that keep blood flowing in the correct direction. In some cases, one or more of the valves don't open or close properly. This can cause the blood flow through your heart to your body to be disrupted.
The lining of the uterus is shed because an ovum has not been fertilized
Past climate changes led to extinction of many species, population migrations, and pronounced changes in the land surface and ocean circulation. The speed of the current climate change is faster than most of the past events, making it more difficult for human societies and the natural world to adapt.
In the twilight zone, the temperature and the light conditions change. The initial 200 meters of the ocean as considered as the open ocean. There is availability of light and thriving temperature there. Butt below that, in the 'deep ocean'. The availability of light decreases and as we go further down, the light no longer reaches those parts of the ocean. Moreover, the temperatures plummet down to almost freezing conditions. In addition to this, the pressure is much more higher in the deep ocean.
