the lens of the vertebrate eye develops only after the head ectoderm comes in contact with the optic cup. This is an example of

Which bonds are found inside a water molecule

Asolid cylinder and a cylindrical shell have the same mass, same radius, and turn on frictionless, horizontal axles. the cylindrical shell has light-weight spokes connecting the shell to the axle. a rope is wrapped around each cylinder and tied to blocks of equal masses that are held the same height above the ground. both blocks are released simultaneously. the ropes do not slip. which block hits the ground first? or is it a tie?

Which two body systems, when working together, give your body shape and allows you to move around, like the boy seen here? a) muscular and skeletal b) digestive and skeletal c) skeletal and circulatory d) cardiovascular and skeletal