ABPI - Resources for Schools

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Diabetes (advanced level)

Age range 16-19

Islets of Langerhans

The pancreas has two functions: to make hormones (endocrine) and to produce enzymes for digestion (exocrine).

The islets of Langerhans make the hormones insulin and glucagon. The alpha cells (stained red) make the glucagon and the beta cells (green) produce insulin. Nuclei are stained blue.

The islets make up only just over 2% of the pancreatic tissue

Alpha and beta cells in the pancreas

Alpha and beta cells in the islets of Langerhans. Source: Masur

Specialised cells

Beta cells are specialised to produce insulin. They have a well-developed rough endoplasmic reticulum, to produce the protein hormone. This is then stored in cytoplasmic vesicles before it is secreted. The process requires energy and beta cells contain many mitochondria to provide ATP.

Roll over the image to see the parts of the cell involved in insulin production.

Protein synthesis

Insulin is a protein and there are several stages in its production. The animation shows the process of protein synthesis. When insulin is being produced, it is the insulin gene in the nucleus that is transcribed into messenger RNA.

Question 5

Which cells produce insulin?
What is the role of the ribosomes in the rough endoplasmic reticulum in the production of insulin?
What is the role of the Golgi apparatus in the production of insulin?
What is the role of the DNA in the production of insulin?
ATP (adenosine triphosphate)
A small organic non-protein molecule that is a source of chemical energy within a cell.
Biological catalysts that speed up chemical reactions.
A hormone produced by the pancreas. It causes the liver to convert glycogen back to glucose and to release glucose into the bloodstream.
A chemical messenger produced by a particular gland or cells of the endocrine system. Hormones are transported throughout the body in the blood stream but they produce a response only in specific target cells
Organelles within cells that produce ATP, used as a store of chemical energy. Often called the cell's powerhouse.
An endocrine gland which produces insulin
Messenger RNA (ribonucleic acid)
Single chains of nucleotide units that transmit the information from the DNA inside the cell's nucleus to the ribosomes in the cytoplasm which synthesise the required proteins.
Rough endoplasmic reticulum
A network of membranes within a cell which has ribosomes attached to it. They are important in the synthesis and transportation of proteins.
A small sac that stores or transports substances inside a cell.