Flatworms also have a feature that the sponges and cnidarians do not, a middle layer of actual organized cells. Flatworms have three cell layers: an ectoderm, an outer covering like the other groups have; an endoderm, a lining of the digestive spaces somewhat like a cnidarians; and a mesoderm between the other two.With actual tissues protected like this, another evolutionary explosion of features happened.latworms have three cell layers: an ectoderm, an outer covering like the other groups have; an endoderm, a lining of the digestive spaces somewhat like a cnidarians; and a mesoderm between the other two. With actual tissues protected like this, another evolutionary explosion of features happened.
Distance, Gas Consumption and Emission Notes. Distance from Houston, TX to Grand Prairie, TX is 253Miles or 407 Km. You can get this distance about 3 hours 38 mins. If you want to planning travel with plane for 228 Miles or 367 Km, You can get this distance about 59 mins . A car with an average MPG will needs 11.71 gallons of gas to get the route between these points.
The following Cities are next to Arlington, TX: 1  Fort Worth is 14.1 miles northwest of Arlington, TX. 2  Grand Prairie is 6.1 miles east of Arlington, TX. 3  Mansfield is 9 miles south of Arlington, TX.  Kennedale is 6.6 miles southwest of Arlington, 1  TX. Pantego is 2 miles northwest of Arlington,  TX.