(1) tobacco use, (2) alcohol consumption, and (3) unhealthy diet and physical inactivity.
Breathing In (Inhalation)
When you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. This increases the space in your chest cavity, into which your lungs expand. The intercostal muscles between your ribs also help enlarge the chest cavity. They contract to pull your rib cage both upward and outward when you inhale.
As your lungs expand, air is sucked in through your nose or mouth. The air travels down your windpipe and into your lungs. After passing through your bronchial tubes, the air finally reaches and enters the alveoli (air sacs).
Through the very thin walls of the alveoli, oxygen from the air passes to the surrounding capillaries (blood vessels). A red blood cell protein called hemoglobin (HEE-muh-glow-bin) helps move oxygen from the air sacs to the blood.
At the same time, carbon dioxide moves from the capillaries into the air sacs. The gas has traveled in the bloodstream from the right side of the heart through the pulmonary artery.
Oxygen-rich blood from the lungs is carried through a network of capillaries to the pulmonary vein. This vein delivers the oxygen-rich blood to the left side of the heart. The left side of the heart pumps the blood to the rest of the body. There, the oxygen in the blood moves from blood vessels into surrounding tissues.
(For more information on blood flow, go to the Health Topics How the Heart Works article.)
Breathing Out (Exhalation)
When you breathe out, or exhale, your diaphragm relaxes and moves upward into the chest cavity. The intercostal muscles between the ribs also relax to reduce the space in the chest cavity.
As the space in the chest cavity gets smaller, air rich in carbon dioxide is forced out of your lungs and windpipe, and then out of your nose or mouth.
Breathing out requires no effort from your body unless you have a lung disease or are doing physical activity. When you're physically active, your abdominal muscles contract and push your diaphragm against your lungs even more than usual. This rapidly pushes air out of your lungs.
The animation below shows how the lungs work. Click the "start" button to play the animation. Written and spoken explanations are provided with each frame. Use the buttons in the lower right corner to pause, restart, or replay the animation, or use the scroll bar below the buttons to move through the frames.
Respect like caring of others feelings and doing them right.
Answer: hotdogs
Answer choices are: hamburgers, chicken, hot dogs, vegan patties
<span>In US the most popular selling grilling meat throughout the summer is the hotdog. </span><span> Americans eat 7 billion hot dogs over the summer season, 150 million hot dogs over the July 4th holiday alone.</span>
Answer:
Heat by constricting the blood vessels in the skin
Explanation:
The body responds to cold by constricting the blood vessels in the skin in order to reduce heat loss. However in the event where the body is overheating, the opposite occurs.
When the body is getting too hot, the blood vessels in the skin actually dilate. This means that the blood vessels get bigger, exposing the blood to colder temperatures to cool the body down (this may be why the skin may seem red after exercising or while it is very hot). Other mechanisms such as sweating also help cool down the body. When sweat is on the skin, evaporation occurs and cools down the sweat droplet, making sure the skin in contact with that droplet also cools down.
