Symptoms and Reasons?

Hi, please could someone help me, i am a student nurse and need some information regarding diabetes. here is my question

Why do people with diabetes experience symptoms such as increased thirst, weight loss, pear drop odour on breath, etc.

I have searched on the interrnet and in all my books but it repeats what the symptoms are over and over but doesnt actually tell me the reason for them.

Any help would be great.

Thanks in advance

Beki

Thanks for that. Beki