Answer:
Surfactant is a liquid produced by the alveoli in the lungs to keep the lungs from collapsing.
Explanation:
Surfactant is a fluid composed of lipids and proteins produced in the lungs that keeps the airways open and prevent the lung from collapsing. It is secreted by the alveolar epithelial type-II (AT-II) cells of the tiny air sacs found in the lungs called alveoli. It prevents the collapse of alveoli under the surface tension by reducing the surface tension at the interface between air and the aqueous fluid lining the alveolar surfaces. If enough surfactant is not present, the surface tension causes the tissue surrounding the alveoli to stick together after each exhalation and results in the collapse of alveoli.
Usually, in unborn babies, the production of surfactant starts at about 6 months of pregnancy and the surfactant helps the babies to breathe in the air immediately after delivery. But a premature baby can not produce enough surfactant and it results in the collapse of alveoli with each breath. The damaged alveolar cells collected in the airways affect breathing and the baby takes in less oxygen. This disorder is known as respiratory distress syndrome (RDS).
The level of carbon dioxide in the blood increases and results in acidosis which affects other organs in the body. Since the premature babies having RDS need extra oxygen and help with breathing, the treatment methods include providing extra oxygen through CPAP, placing a breathing tube into your baby's trachea, providing artificial surfactant and ventilator support.
Answer:
Stalagmites and stalactites are some of the best known cave formations. They are icicle-shaped deposits that form when water dissolves overlying limestone then re-deposits calcium carbonate along the ceilings or floors of underlying caves.
<span>The answer would be: body cells that have been infected
Cytotoxic comes from word cyto- which mean cells and toxic which mean poison. That means cytotoxic cells will be poisonous to the cells. C</span><span>ytotoxic t cells roles are to attack cells that infected by pathogens. Some pathogens hide inside the cells so that they won't captured by the leucocytes.
</span><span>Cytotoxic t cells destroy such cells so the pathogens inside them could be killed.</span>
This is true. The impact of human on trees has been completely
negative. This includes deforestation which causing negative effects on the environment.
A massive scale of Earth’s forest has been cleared through deforestation. This
results to the damage of the land quality.