Which of the following best describes the function of the immune system's response to bacterial invasion of the extracellular fl
uid? a. a system that produces swelling and redness at the site of infection in order to flush out bacteria from the extracellular fluid
b. a system that inhibits the production of antibodies and histamine, resulting in bacterial death
c. a system that uses only intracellular chemicals to destroy invading bacteria
d. a system that enhances the destruction of bacteria through the activation of mast cells, lymphocytes, and phagocytes
d. a system that enhances the destruction of bacteria through the activation of mast cells, lymphocytes, and phagocytes
Explanation:
Mast cells are white blood cells (i.e., lymphocytes) that form part of the immune system. These cells form part of the first line of defense against pathogenic organisms. Some of the most important phagocytic cells that function to protect the body by ingesting pathogenic agents (e.g., harmful bacteria) include mast cells, monocytes, neutrophils, macrophages and dendritic cells. In this regard, it is important to highlight that mast cells are similar to basophil granulocytes (another type of lymphocyte), and they are derived from hematopoietic stem cells.
They are said to be “denser” than air. what happens is that light slows down when it passes from the less dense air into the denser glass of water. this slowing down the ray of light also causes the ray of light to change directions. it is the change in the speed of the light that causes refraction.
