Flatworms, nematodes, and cnidarians (jellyfish, sea anemones, corals) do not have a circulatory system and therefore no blood. Their body cavities have no lining or liquid in them. They get nutrients and oxygen directly from the water they live in. 23 мар. 2015 г.
Which animal does not have a cardiovascular system?
The simplest animals, such as sponges (Porifera) and rotifers (Rotifera), because diffusion allows for the proper exchange of water, nutrients, waste, and dissolved gas, as shown in Figure 1a. Does not require a circulatory system. ..
Which insect does not have a cardiovascular system?
With the exception of some aquatic insects, the blood lymph of insects does not contain hemoglobin (or red blood cells). Oxygen comes from the tracheal system, not the circulatory system.
Below you will find two helpful answers on a similar topic. 👇
Is there any evidence of nervous or circulatory systems in sponges?Do sponges have a digestive system?
