Solve full and also give reasons

Dear student 
Please find your answer below to the asked query 

1. Tonsils. 
All other are types of blood vessels. 

2. Urea. 
All others are high molecular weight protein. 

3. Erythrocytes
It is RBC and all other are type of  white blood cells. 

4. Left ventricle 
Its a part of heart and all other vessels. 

5. Blood sugar
All others are related to cardiac problem. 

Regards