Answer:
<u>c. Sucrose and glucose</u>
Explanation:
The paramecium is a large, single-celled microbes, surrounded by a plasma membrane. Simple diffusion occurs in cells across plasma membranes, as a form of passive transport. In diffusion, solutes move from regions of high concentration to regions of low concentration across the plasma membrane.
Here, the internal environment has higher concentrations of sucrose and glucose, but lower concentrations of fructose, thus the solutes will move along their concentration gradient, to where the concentrations are lower. In order for the fructose molecules to move out of the cell, the molecules have to move against their concentration gradient - a process requiring energy known as active transport.
<span>Leather shoes are made from natural polymers; raincoats are made from synthetic polymers. </span>
Humans, like all mammals, are diploid organisms. This means that we have two copies of each chromosome. In diploid organisms, one somatic cell would have two copies of each gene. This means that in one somatic cell, an individual carries two copies of alleles for long eyelashes, and also two copies of alleles for short eyelashes.
A. Cerebellum
By far the largest region of your brain is the forebrain (derived from the developmental prosencephalon), which contains the entire cerebrum and several structures directly nestled within it - the thalamus, hypothalamus, the pineal gland and the limbic system.
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.
