Answer:
Most cells within planarians tend to be very close to their gastrovascular cavity, in addition to their external environments. Also, planarians have the ability for oxygen and carbon dioxide to diffuse through the cells on their body walls: this makes it unnecessary for these varieties of flatworms to need a dedicated bodily system.
I think the deficiency of dedicated respiratory and circulatory systems in Planarians does not cause a problem because none of their cells are far removed from the gastrovascular cavity or from the external environment. Planarians are free-living flatworms and form the class Turbellarians in the Phylum Platyhelminthes. Flatworms have three tissue layers, that is the ectoderm, mesoderm, and endoderm.
hope this helps!!!!!....
Explanation:
<h2><u>Answer:</u></h2>
Amid the Ordovician Period, the outside of the earth was drastically unique in relation to it is today. About all life on earth was in the seas. The main land life was as exceptionally crude plants extremely close to the water line of the coasts, presumably greeneries and green growth and were of a non-vascular nature.
The Ordovician Period started with a noteworthy eradication called the Cambrian– Ordovician annihilation occasion, about 485.4 Mya (million years prior). It went on for around 42 million years and finished with the Ordovician– Silurian elimination occasions, about 443.8 Mya (ICS, 2004) which cleared out 60% of marine genera.
The timeframe that occurred 488 to 443 million years back. Amid the Ordovician time frame, some portion of the Paleozoic time, a rich assortment of marine life thrived in the tremendous oceans and the primary crude plants started to show up ashore—before the second biggest mass annihilation ever finished the period.
As the flower takes water that it needs to survive, the dye in it has no more density so it goes up with the water dying everything in its path blue.
