Homeostasis & Negative Feedback - exam practice

What is/are intervention(s) in the immediate control of high blood glucose concentration?

1 - insulin injection

2 - regular cardiovascular exercise

3 - glucagon injection

Banting and Best pioneered experiments into the functions of the pancreas.

In one experiment, they removed the pancreas of dogs. Shortly afterwards, the dogs developed the symptoms of diabetes.

• Banting ground up the removed pancreas to produce an extract

• he called the extract 'isletin'

• the isletin was then injected into dogs that had had their pancreas removed

• he then tested the blood glucose concentration

The graph below is a summary of the results.

Which of the following statements correctly explains these results?

1 - isletin is made in the α cells in the islets of Langerhans

2 - isletin reduces blood glucose concentration

3 - the effects of isletin are short lived

What is true of type 2 diabetes?

What describes an indirect role of glucagon?

What type of cells detect stimuli in the body?

What do effectors do in response to stimuli?

What is the primary purpose of homeostasis?

What type of feedback mechanism restores normal levels after a change?

Why isn't positive feedback involved in maintaining homeostasis in humans?

How do hormones reach their target cells in the body?

Which glands secrete hormones directly into the bloodstream?

In the hormonal system, what do second messengers do?

What is a common treatment for type 1 diabetes?

Which cells in the pancreas secrete insulin, and what triggers this?