The histology of the esophagus and
the stomach will be explained in this
lecture. And also, these histological
components and descriptions will
be related to the function of these two
organs. At the end of this lecture, I'd
like you to know the characteristics of the
wall of the gut. It's very important that
you can identify each of the components of
the wall of the gut, and to realize that
the main component that changes all the
way along the gut tube is the mucosa.
In this lecture, I'm going to talk about
the mucosa of the esophagus and the stomach.
But in other lectures, I'm going to talk
about the mucosa of all other parts of
the digestive system. I'm going to also
briefly mention that there are endocrine
cells in the mucosa all the way along the
gut. There's also cells there as part
of the immune system. And also, a lot
of the muscular layers of the gut are
controlled by an independent nervous
system, the enteric division of
the nervous system. It's independent of the
brain and the spinal cord. So hopefully,
at the end of this lecture, you will
appreciate all these details.
The esophagus is very important because it
carries the food that's broken down
partially, mechanically at least, in the
oral cavity into the stomach. And then the
stomach is then further physically
broken down because of the mixing
activity in the stomach
produced by the muscular walls
of the stomach.
And also, there's chemical digestion
going on in the stomach as well.
The stomach is also a very special mucosa
because it contains a number of
different secretory cells that produce
various secretory products that aid
in the chemical digestion of the food or
the chyme in the lumen of stomach.
So it's important that you understand all