java继承中的super调用

最近看到了下面一段代码，都是覆盖父类的方法，为什么onCreate方法就需要调用super.onCreate(..)，而onActivityResult(..)方法就不需要调用super.onActivityResult(..)呢？求哪位解释一下
public class MainActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
...........

}

@Override
protected void onActivityResult(int requestCode,int resultCode,Intent data){

switch(requestCode){
case TAKE_PHOTO:
    if(resultCode==RESULT_OK){
        Intent intent=new Intent("com.android.camera.action.CROP");
    ...........

}