The answer is A. Encloses the heart
The pericardium is the thick, membranous, fluid-filled sac that surrounds the heart and the roots of the vessels that enter and leave this vital organ, functioning as a protective membrane. The pericardium is one of the mesothelium tissues of the thoracic cavity, along with the pleura which cover the lungs.
The heart is located within the thoracic cavity, medially between the lungs in the mediastinum. It is about the size of a fist, is broad at the top, and tapers toward the base. Within the mediastinum, the heart is separated from the other mediastinal structures by a tough membrane known as the pericardium, or pericardial sac, and sits in its own space called the pericardial cavity.
True, they may not be permanent, but can sure occur. <span />
Answer:
Decrease in pressure
Explanation:
In the respiratory pump process to increase venous return, inhalation results in a decrease in pressure in the thoracic cavity, which causes the inferior vena cava and right atrium to expand and fill with blood.
Answer:
Incidence
Explanation:
Isaac will need to assess the incidence rate of HIV-infected adolescents for his research. This must be done because Isaac's research wants to gauge the speed with which this virus is spreading among teens. For this, Isaac must make a comparison between the existing number of patients who fit this case, with patients who fit the recent cases of incidence of the disease. That is, when conducting his research, he will want to examine the number of new cases, the incidence of the disease.