The enzyme alpha amylase can be found in saliva and helps to start the digestion of food. In order to work optimally, calcium and chlorine ions must be bound to it. In this example, calcium and chlorine are examples of...

The body is protected against harmful flu viruses by

The nervous system interacts with the endocrine system by a. using hormones as connections b. sending nerve impulses directly to glands c. using neuroendocrine cells as connections d. sending neurotransmitters directly to neurons

When you run, you begin to breathe heavier and faster. your heart beats more quickly, bringing more oxygen to your cells. which organ systems are working together here?