to enable them have free movement in their surrounding environment
Because there are no frictional forces.
There are many different streamlines object. The streamlined object is the object that air hits it least. Any object that is pointy or Begin with small part to a big part this is streamlined object.
like deflectors on lorries
torpedo bullet arrow car motorbike
Being streamlined reduces friction and water resistance because it reduces the surface area in front this allows objects to move quickly through air or water.
To reduce turbulent the key is to have streamlined shape of an object.
A list of streamlined animals-SnakesAnimals that live undergroundMost aquatic animalsTreefrogsBirds
Lorrys air not streamlined beacuse there is no where for the air to go when it hits the truck. But some lorries are streamlined but not to the exstent of cars like the renault k-80 which has curves to direct the airflow
Streamlined body and large lungs
To reduce air resistance or drag.
The shape of many objects moving through air or water is designed in such a way(with pointed ends) that friction can be reduced between the objects and water or air(fluid).The shape of the body is called streamlined body. Most fish are cold-blooded animals that have a streamlined body that is adapted for efficient movement in water. There are exceptions to both of these rules though.