The protozoans are mobile in nature, moving by means of pseudopodia, cilia,undulating membrane or flagella. Some are sessile.The sarcodines move by the use of pseudopods(body projections), ciliates by cilia( hair like structures), flagellates by flagella(whip-like structure) and parasites like paramecium using undulating membrane(undifferentiated membrane).
In the patellar tendon reflex arc, the quadriceps femoris contracts when the quadriceps femoris of the the thigh is stretched through the stretching of the patellar ligament. This also causes the hamstring to relax
