Pyruvate dehydrogenase is regulated by feedback inhibition and covalent modification. Which molecules inhibit the pyruvate dehydrogenase complex? a. NADH and CO2
b. Acetyl-CoA and CO2
c. NADH, CO2, and acetyl-CoA
d. NADH and acetyl-CoA

b brown mice / white sand dunes

the fossil record provides evidence of a common ancestor to many species.

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.