Your mouth, nose, throat, sinuses and lungs are lined with mucus membranes. These membranes contain mucus glands that produce - surprise - mucus. Mucus-producing membranes line specific passages in your body, like the respiratory and digestive tracts, for protection and support.
Answer:
Both the respiratory and circulatory systems works in coordination in order to purify the blood.The heart continuously pumps blood and the lungs at alveolar sacs the CO2 and O2 get exchanged.Continuously through the diffusion.
From body parts the blood reaches at heart through Vena cava To right atrium,then from Right ventricle through pulmonary artery it reaches to lungs and get purified.Form there it again comes back to heart through pulmonary vein and again through Aorta it again reaches to the body parts.
Hope it helps....
B. Adolescents need more calories and nutrients, especially if they are very inactive.
Answer:
peanut butter, oatmeal, milk, nuts, red meats, fish, potatoes, protein shakes, dried fruit, whole-grain bread, avocados, dark chocolate, cheese, and whole eggs
-the burning of fossil fuel
-natural events
-waste in landfills
-agricultural activities
-mining operations
-etc