What causes Type 1 diabetes?

An autoimmune response in which the immune system destroys beta cells in the islets of Langerhans.

Why are people with Type 1 diabetes unable to regulate their blood glucose concentration naturally?

Because their beta cells have been destroyed, they are unable to produce insulin.

What are the two possible causes of Type 2 diabetes?

Reduced responsiveness of body cells to insulin (insulin resistance) or a decline in insulin production.

State four risk factors associated with Type 2 diabetes.

Obesity, lack of exercise, age, and genetic predisposition.

How is Type 1 diabetes treated?

With insulin injections, which must be carefully timed with meals and blood glucose monitoring.

Describe the progression of treatment for Type 2 diabetes.

Initially treated with lifestyle changes including controlled diet and increased exercise; may progress to oral medication or insulin injections if these are insufficient.

OCR A-Level Biology H420

Cell Structure

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Hormonal Communication

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Hormonal Communication

Diabetes and its treatment

1 thing to know
Components 01 and 03

Overview

What causes Type 1 and Type 2 diabetes and the risk factors involved, how each is treated, and the use of genetically modified bacteria and of stem cells.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Evaluation

State three advantages of using insulin produced by genetically modified bacteria compared to animal-derived insulin.

Questions from this subtopic

Each one with the model answer underneath.

1
What causes Type 1 diabetes?
Model answer
An autoimmune response in which the immune system destroys beta cells in the islets of Langerhans.
2
Why are people with Type 1 diabetes unable to regulate their blood glucose concentration naturally?
Model answer
Because their beta cells have been destroyed, they are unable to produce insulin.
3
What are the two possible causes of Type 2 diabetes?
Model answer
Reduced responsiveness of body cells to insulin (insulin resistance) or a decline in insulin production.
4
State four risk factors associated with Type 2 diabetes.
Model answer
Obesity, lack of exercise, age, and genetic predisposition.
5
How is Type 1 diabetes treated?
Model answer
With insulin injections, which must be carefully timed with meals and blood glucose monitoring.
6
Describe the progression of treatment for Type 2 diabetes.
Model answer
Initially treated with lifestyle changes including controlled diet and increased exercise; may progress to oral medication or insulin injections if these are insufficient.

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