Question

Natural killer lymphocytes

A) the squeezing of cells through thelining of capillaries to attack invading microbes
B) nonspecific leukocytes that secrete toxins onto the surface of virally infected cells
C) the movement of a cell towards or away from a chemical stimulus
D) increase in number of allergies and helminth infection
E) the coating of a pathogen by complement

Answer 1

Natural Killer Cells are lymphocytes that can kill cells infected with viruses or abnormal cells by triggering apoptosis. They identify these cells through the altered expression of major histocompatibility complex (MHC) I molecules. The correct option is B) nonspecific leukocytes that secrete toxins onto the surface of virally infected cells

Step-by-step explanation:

Natural Killer Cells, or NK cells, are a type of lymphocyte that can kill cells infected with viruses or abnormal cells, such as cancerous cells. NK cells identify infected or abnormal cells by the altered expression of major histocompatibility complex (MHC) I molecules on the surface of these cells.

MHC I molecules are proteins found on the surfaces of all nucleated cells, and their function is to display fragments of proteins from infectious agents within the cell to T cells. When NK cells recognize these cells, they release proteins that trigger apoptosis, resulting in the death of the infected or abnormal cell. The correct option is B) nonspecific leukocytes that secrete toxins onto the surface of virally infected cells