Answer:
the umbilical cord is connected to both the mother and the unborn child and so tranfers nutrients from the mothers blood to that of the baby's blood
Answer:
The answer is day 14 - / + 3 days
Explanation:
In a 28-day menstrual cycle the most likely days for a woman to become pregnant is from day 14 - / + 3 days, that is, days 11, 12, 13, 14, 15 and 16. She should be educated, If she is in search of pregnancy, take the vaginal temperature and realize how the viscosity of the abundant flow begins to present.
Answer:
They fight against infections and disease.
Explanation:
These alveoli are the smallest types of lung tissue, and one of the most important. In addition to being the primary means by which oxygen enters and carbon dioxide escapes the bloodstream, these small pouches of air are also the reason why the lungs do not totally collapse when a person breathes out. This is because they contain a cell that secretes a special chemical to lower the surface temperature to prevent lung collapse. The alveoli also contain other cells that secrete chemicals to attack and remove any foreign objects in the lungs, such as dust, dirt and other debris.
In addition to making up alveolar sacs, alveoli also form alveolar ducts. It is estimated that there are more than 300 million alveoli in the human lungs, all of which are located in either alveolar ducts or sacs that are found at the end of the smaller passageways, or bronchioles, in the lungs.
SHORT ANSWER:
Alveolar sacs contain tiny pouches called alveoli, whose primary function is gas diffusion. These clusters of alveoli have thin walls that allow oxygen to pass easily from the lungs into the bloodstream and carbon dioxide to flow from the blood to the lungs so it can exit the body.