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.
OK so based on the options given I would like to say that the answer is A. because if you think about it logically it is the only answer that makes sense.
Answer:
A great deal of both physical and psychological energy is needed for parenting tasks.
Careers and other activities deplete some of the parents energy and to this depletion is added all the parenting tasks.
Answer:
1. (B) Interferen-V
2.(E)
3.(E)
Explanation:
1.Interferon-V is the most important in the pathogenesis of this lesion because, it promotes the formation of epithelioid cells and giant cells.
2.Immunoglobulin will be increased in response to inflammatory responses with allergins and with invasive parasites.
3.The most likely mediator for the fever is interleukin-1 ( IL-1) and tumor necrosis factor, TNF, which are produced by macrophages and other cell types.
