Digestion starts in the "mouth" and continues in the stomach. The small intestine completes the digestion process.
A karyotype cannot determine if an organism is male or female. I am pretty sure that is the answer.
Sound cannot travel through a vacuum. A vacuum is an area without any air, like space. So sound cannot travel through space because there is no matter for the vibrations to work in.
The substrate and the active site both need to fit together perfectly in order for the enzyme to work properly. If their shape is changed, typically through heat or a change in pH, the enzyme will not work.
