Here's a blood transfusion activity to accompany your Circulatory System unit. There are TWO different sheets, and each has ten questions. As students answer questions about blood type compatibility, blood is transfused into the patient's arm on Sheet 1 and is donated (comes out of the patient's arm) on Sheet 2. The digital sheet is self-grading, so NO PREP on your part. It is also available as a printable PDF. An answer key is included.