The environment selected is favorable to ponies with longer legs.
Stalactites <span>show a possible evolution of a cave formation.</span>
This statement is true, because the warmer the temperature, the faster the atoms move in a liquid
Answer:
The fewer number of T cells a person has, the more chances to be affected by an opportunistic infection. When the number of T cells reaches 200 cells/µl, the person is at risk of being infected by other infections.
Explanation:
The whole immune system of a person who is infected with HIV infection seems to be severely affected. When the person is not treated or the disease is in a very advanced stage, the depletion of the T- cells turns to be very sharped, especially CD4+ T cells. At this point, the immune system can not resist the attack of other microorganisms. The <em>lower is the number of CD4+ T Cells, the higher possibility the person has to be attacked by opportunistic infections. </em>
Classically, it has been suggested that opportunistic infections appear after the CD4 + T lymphocytes reach very low levels, such as 200 cells/µl. The number of circulating T cells can be used as an indicator and a measure of global "immune competence", and the previously mentioned amount of CD4 + T cells is an accepted universal reference used to predict the risk of having one of these opportunistic infections.
Answer/Explanation:
In humans, we breathe in oxygen via the respiratory system. The oxygen enters the lungs. The air sacs in the lungs - the alveoli - are the site of gas exchange in the lungs and are where the circulatory and respiratory systems interact.
The alveoli take in the oxygen, where it diffuses into the capillaries (circulatory system). Blood, which passes through the capillaries takes this oxygen to all the cells in the body. Oxygen binds to haemoglobin in red blood cells, which transport it around the body.
Additionally, blood also transports carbon dioxide back to the alveoli of the lungs, where it diffuses into the lungs and is expelled when we breathe out
