Each year, a few people with type I diabetes are given a pancreas transplant. Pancreas transplants are not used to treat people with type II diabetes.

Give two reasons why pancreas transplants are not used for the treatment of type II diabetes.

1

2

The pancreas produces the hormone insulin.

Put a tick (✓) in the box next to the statement which describes incorrectly the action of insulin.

☐ Activates enzymes involved in the conversion of glucose to glycogen.

☐ Controls the uptake of glucose by regulating the inclusion of channel proteins in the surface membranes of target cells.

☐ Attaches to receptors on the surfaces of target cells.

☐ Activates enzymes involved in the conversion of glycerol to glucose.

Scientists investigated the use of induced pluripotent stem cells (iPS cells) to treat type I diabetes in mice. The scientists used four transcription factors to reprogramme skin cells to form iPS cells. The scientists then stimulated the in vitro differentiation of iPS cells into pancreatic cells.

The scientists set up three experimental groups:

• Group A – 30 mice with type I diabetes received pancreatic cell transplants derived from iPS cells. • Group B – 30 mice with type I diabetes were left untreated. • Group C – 30 mice without diabetes were left untreated.

The scientists measured the blood glucose concentration of all the mice on a weekly basis for 12 weeks.

Suggest how transcription factors can reprogramme cells to form iPS cells.

Using all the information provided, evaluate the use of iPS cells to treat type I diabetes in humans.