Jeremiah has an infection on his pinky finger that developed as a result of a simple cut. as the infection first penetrates the skin, what type of cell would be responsible for engulfing the offending invaders to prevent them from doing any damage?

The correct answer is "phagocytes".

Phagocytes are cells responsible for fighting infection by engulfing and ingesting bacteria and harmful foreign particles. Once phagocytes come in contact with any foreign and dangerous particle, they bind to them and engulf them. This mechanism of action is called phagocytosis. 

Carbon-14 has a half-life of 5,730 years and most igneous rock is older than that.