The heart is one of the first parts of the embryo to develop. what part of the stem cell provides instructions for building the heart?

The embryonic stem cell provides instructions for building the heart. The embryonic stem cell is also in charged in making the other organs to form the fetus. These cells came from the embryo which functions to regenerate the damaged cells during a disease. 

both anaerobic and aerobic respiration use glucose (or other carbohydrates), proteins and lipids to produce atp and nadh. cell uses those energy molecules, obtained from food and   breaks them down during the chemical reactions of respiration. in anaerobic respiration, nadh is regenerated to nad+ by enzymes lactate dehydrogenase (lactate is produced, e.g. in muscle cells) or by alcohol dehydrogenase where ethanol is produced (alcohol fermentation), while in aerobic respiration, electrons from nadh are deposited in the mitochondria to regenerate nad+ (electron transport chain. anaerobic respiration produces 2 atp per molecule of glucose compared to aerobic respiration where about 38 atp molecules are produced.

1. what is the relationship between the shape of an enzyme and the reactions they catalyze?

2. how does an enzyme inhibitor work?

separate your answers so i dont get confused : )