D.) Both are circumstantial evidence....
Answer:
Helper T cells stimulate B-cells to produce antibodies and killer T cells to destroy the non-self cells. Cytotoxic T cells on the other hand are direct attack cells. They can kill the micro organisms by creating pores on the invader's cell.
Explanation:
T lymphocyte mediated immunity of cell mediated immunity do not secrete antibodies but they help stimulate the B cells to produce them. Immature T cells are produced in bone marrow from where they migrate to thymus via blood. In the thymus maturation of T cells occur and then they migrate to lymphoid tissue and get differentiated into three types:
a. Helper T cells: As the name suggests, they help in activating other immune cells, in other terms they are the regulator of virtually all functions of immune system. Protein mediator called lymphokines are produced by these helper T cells in order to regulate the immune functions. Some examples of these lymphokines are: Interleukin-2 interleukin-3, interferon gamma. T helper cells stimulate the B-cells to produce antibodies.
b. Cytotoxic cells or killer T cells: The lymphokine interleukin-2 is responsible for the growth and proliferation of both cytotoxic T cells and suppressor T cells. With the help of receptor proteins on the surface of killer T cells, they bind to the specific antigen. After binding, they secrete a pore forming protein called perforins which create pores on the invaders cell membrane for water to enter into it thereby cell swells and finally lyse.
c. Suppressor T cells: They suppress the function of above two T cells.
The correct option is B, that is, A FAMILY DONATES USED CLOTHING TO A SECOND HAND STORE.
Waste prevention has to do with the process and practice of reducing the amount of wastes products in order to produce a more sustainable environment. Waste prevention can also be called recycling. There are three types of waste prevention, these are primary, secondary and tertiary waste prevention / recycling.
Primary waste prevention refers to a situation in which the material to be disposed is not changed in anyway, before been reused. Such material can be given to friend or donated to a charity organization. The material is always used for the same purpose as the original use.
Secondary waste prevention involves some kind of modifications while tertiary waste prevention usually involves the use of chemicals and heat.
It would cause Rain. But a cold front. Fronts are always in relation to moving cold air A cold front is the advancing edge of a cold air mass and a warm front is the retreating edge of a cold mass. If the cold air mass is displacing the warm air front then the cold air is advancing.
