Whats happend to my body if i crack a rib?

Collapsed lung

Explanation:

Collapsed lung: A broken rib may tear your lung or chest wall, which can cause your lung to collapse. Signs that this has happened include trouble breathing, coughing up blood, and severe chest pain.

regulation of gene expression. gene expression can be regulated by various cellular processes with the aim to control the amount and nature of the expressed genes. these regulatory proteins bind to dna and send signals that indirectly control the rate of gene expression

explanation:

answer; /// i believe the correct answer is (reactants);