Steve is a construction worker. he cut his hand deeply. the cut became infected. which kind of immune defense was broken in his immune system

The kind of immune defense that was broken in his immune system is the skin.

While many do not look at it this way, the skin is the largest organ in the body. It plays a key role in our immunity and protects us from many, many dangers.

Hope I could help. 

Probably because you wake up early. even when i get a good nights sleep i still feel tired if i wake up early. or maybe you just need coffee.