Answer:
The complex eukaryotic cell ushered in a whole new era for life on Earth, because these cells evolved into multicellular organisms. Evidence supports the idea that eukaryotic cells are actually the descendents of separate prokaryotic cells that joined together in a symbiotic union.
Q1:
Answer:
Studies have reported that due to predation of pythons on rabbits, the population of other predators is badly affected.
Bobcats are a natural predator of rabbits thus they come in a competition with pythons for food. As pythons are more powerful so they target rabbits more easily than Bobcats. The population of Bobcats has been declined by 90% or more due to the establishment of pythons in the Everglades.
<em>Alligator mississippiensis </em>or American alligators are also abundant in Everglades and just like Bobcats they compete with pythons for their food. They can even kill pythons if pythons are smaller in size than them, but python will kill alligator if he is of smaller size. Although rabbits are food for both alligator and Python but Alligator is a key stone specie and it has very important ecological role, because it digs holes in land that retain water upon rainfall. These water hole provide water in the extreme dry weather and help in survival of other small specie like insects and birds.
So, we can expect the population of Alligator, Bob cats and other small insects and birds to decline rapidly if Python population kept on increasing with same speed.
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Q2:
Answer:
There is no doubt that Pythons pose serious threat for both humans as well as survival of other organisms like Alligators and birds. However, I donot think that “Python challenge” is a reasonable way to kill or remove Pythons. Because It can threat the lives of many individuals who take part in competition, although they are trained but still they are nor professionals and get training of only few weeks so it is not safe competition.
There should be some strategy of introducing natural predators like Brown beers, Cougars and Alligators which can kill python naturally without staking the life of humans at risk.
Hope it helps!
Absolutely.
in doing so,they can create more idea Conditions for growing crops to feed the planet.
on the flip side...they look to control the prices of commodities (grain) on a global stock market,more so than they already do.
want to lower the price?...flood the market.
want to raise prices? ...control the climate and with hold surpluses
I think b.only select generation are effective...
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.
