Answer:
When you are hungry your brain signals your digestive system to prepare for food. This leads to stomach growling. Your brain does this because it knows that you are hungry, and consequently the brain signals the digestive muscles to contract. There is also, usually, some gas in the intestines and stomach. The noises come out when the mixture of the gas and fluid, digestive juices, squirt through a opening that separates the stomach and small intestine.
Sometimes the noises happen because of an excessive amount of gas in the small intestine.
Explanation:
Factories, cars, oil producers, woodcutting, building houses, and even building new roads makes the carbon cycle harder to go through.
The answer is 0.40 that’s the average
Answer:
1. Ends of the respiratory branches are called alveoli.
2. C. To control blood flow to different areas of the body depending on activities
Explanation:
1. The trachea divides into left and right primary bronchi which in turn divide multiple times upon entering the lungs and make the bronchial tree.
The final branches of the bronchial tree are the terminal bronchioles that lead to alveoli. The alveoli are the balloon-shaped structures and serve as the site of gas exchange between the blood and inhaled air.
2. The opening and closing of sphincters of capillary beds regulate the direction of blood flow. The opening of sphincters allows the blood to flow into associated branches of capillary beds while closed sphincters direct the blood from arterioles to venules via thoroughfare channel.
This local change in blood flow is responsible for the autoregulation of blood flow to different tissues to match their respective metabolic demands. For example, during physical activity, more blood is directed to skeletal and cardiac muscles.
