Stomach acid<span> plays an essential role in the immune system by killing harmful bacteria and parasites that are ingested with food. </span>Stomach acid<span> activates the enzyme pepsin needed for protein </span>digestion<span>. </span>Stomach acid<span> signals to the pancreas produce </span>digestive<span> juices and enzymes to further break down food.</span>
Answer:
The answer to this question is given below in this explanation section.
Explanation:
"advantages of interconnecting air sacs for birds"
The air sacs permit a unidirectional flow of air through the lungs.Unidirectional flow means that air moving through birds lungs is largely fresh air and has a higher oxygen content.In contrast air flow is bidirectional in mammals moving back and forth into and out of the lungs.As a result air coming into a mammals lung is mixed with old air has less oxygen. so in bird lungs,more oxygen is available to diffuse into the blood(avian respiratory system).
- The air sacs are thin membrane structures connected to the primary or secondary bronchi via ostia and they comprise most of the volume of the respiratory system.
- Air sacs are poorly vascularized by the systemic circulation and do not directly participate in significant gas exchange but act as a bellows to ventilate the lungs.In most species,there are nine air sacs which can be considered in cranial and caudal functional groups.
- The cranial group consists of the paired cervical air sacs,the unpaired clavicular air sacs and the paired cranial thoracic air sacs.
One example is using tree rings on a tree to determine the absolute time
The variable did the specialists purposefully differ in the test, and what are the units for this variable is thyroid hormone level of the rats decided for the analysis, in relative units. I hope the answer will help you.
Answer:
B. She was on the continental shelf, not the continental rise.
Explanation:
The continent first contacts the ocean at the continental shelf. After a while, the continental shelf ends in a steep decline known as the continental slope. The continental slope eventually levels out into a gradually sloping continental rise which eventually becomes the ocean floor.