Cell - Egg Cell
Tissue - Muscle tissue
Organ - Lung
Organ system - Respiratory system
Organism - Dog
Anything that relates to sexual reproduction (gametes coming together to fertilize) should be crossed off.
Not much context was provided but you can look back to some other questions I've answered, I have a full in-depth answer to the same question another person had.
The upper part of graft combination is called scion.
