The lumen of the trachea is lined by pseudostratified columnar epithelium. Note that all the surface cells have cilia at their free (apical) surface. (What function do these cilia serve in the trachea?) Mucus-secreting unicellular gland cells (goblet cells) are interspersed among the ciliated cells.
Donât think you need to be able to do the modified version perfectly before you try theseâyou just need to feel brave enough to go upside down. To complete a handstand push up: 1  Face a wall in a standing position.  Kick your feet up so youâre in a handstand position against a wall.
Push ups are done by pushing oneself up off of the ground (arms only) and pull ups are done by lifting oneself up by means of an elevated bar. Pull ups are much harder to do. Different muscles are exercised by these two types of exercise.