Video Transcript
The diagram given shows the basic
outline of the human digestive system. The pancreas produces and releases
a large amount of digestive enzymes. Which number points to the pancreas
on the diagram?
The question asks us to identify
the pancreas on a diagram of the digestive system, so let’s begin with a quick
review of the process of digestion.
The digestive system helps us to
extract essential nutrients from our food, and these nutrients allow our bodies to
undergo growth and repair. Digestion begins when food is
ingested through the mouth. Here, the teeth start mechanical
digestion by physically separating food, while the enzyme amylase begins chemical
digestion by breaking down the carbohydrate starch.
Once food is swallowed, it will
travel through the esophagus to the next stop in the digestive process, the
stomach. Here, digestion continues with the
help of secretions from accessory organs, which are organs that food does not
directly pass through, but which are part of the digestive system. Accessory organs include the liver
and the pancreas.
The liver produces bile, which is
not an enzyme but rather a substance that emulsifies fat molecules, meaning it
breaks them into smaller droplets. Emulsification of fats is a crucial
step because it gives fat-digesting enzymes, called lipases, better access to the
lipid molecules. So, the liver is an accessory organ
of the digestive system because it increases the efficiency of fat digestion.
The pancreas, which sits behind the
stomach, secretes protein-digesting enzymes called proteases, as well as lipases and
amylase, into the top of the small intestine. Interestingly, the pancreas also
produces several hormones, including insulin and glucagon, which are responsible for
regulating blood glucose levels. These hormones are secreted
directly into the bloodstream, instead of through ducts. This means that the pancreas is
considered both an endocrine and an exocrine gland.
Once food has been chemically and
mechanically digested in the stomach, it will move into the small intestine, which
is the main site of nutrient absorption. Despite its name, the small
intestine is nearly seven meters long when uncoiled. After all the useful compounds in
the food have been absorbed, the remaining waste products make their way to the
large intestine. This organ is responsible for
absorbing water and creating solid waste products. These wastes are then released from
the body to complete the digestive process.
Now that we’ve reviewed each organ
in the given diagram, we can answer our question. The number that points to the
pancreas on the diagram is two.