1. Stomach, Breaks down food with acid located in the stomach
2.Mouth, Chews and Grinds food down. Allows the breakdown of enzymes
3.Kidneys, Take out any unhealthy/unneeded substances in the food.
4. Large Intestine, The formation of feces.
<span>In the "all or none" law of muscle contraction, it states that when the stimulus applied exceeds threshold then the the nerve sending signals to a few muscle fibers will give a complete response; contraction. Graded response is dependent on how many motor units have been recruited. The more motor units, the greater the force in the contraction.</span>
D. because if they're not careful they become extinct by predators, then they have to be careful to survive by staying alert.
Please help.
autism