Video Transcript
The endocrine cells of the pancreas
are called islets of Langerhans. What two types of cells make up the
islets of Langerhans?
This question asks us about the
pancreas, which is a very important organ in the human body, with both endocrine and
exocrine functions, and as a result is often referred to as a mixed gland. This question focuses on the
pancreatic endocrine cells, which are found in regions called the islets of
Langerhans.
Endocrine glands are made up of
groups of specialized cells that secrete hormones directly into the blood. Some of the major hormones that are
secreted by the endocrine cells of the pancreas include insulin and glucagon, both
of which are responsible for regulating our blood glucose levels within a healthy
range.
When blood glucose decreases to a
value lower than this range, cells within the islets of Langerhans called 𝛼 cells
usually secrete a hormone called glucagon into the bloodstream. One of the various effects that
glucagon has on the various body cells it acts upon is stimulating the liver cells
to break down glycogen stores into glucose, which is then secreted into the blood,
thereby helping to increase blood glucose back to a healthy range.
When blood glucose increases above
the normal range, 𝛽 cells in the islets of Langerhans usually secrete a hormone
called insulin into the bloodstream. Insulin also has various target
cells, including the liver cells that are encouraged to take up more glucose and
convert it into glycogen to store it, thereby reducing blood glucose concentration
back to a healthy range.
Having reviewed some of the
endocrine functions of the pancreas, we have found the correct answer to this
question. The cells that make up the islets
of Langerhans in the pancreas are 𝛼 and 𝛽 cells.
