Answer:
Hurricanes are large, swirling storms. They produce winds of 119 kilometers per hour (74 mph) or higher. That's faster than a cheetah, the fastest animal on land. Winds from a hurricane can damage buildings and trees.
tornado is a violent rotating column of air extending from a thunderstorm to the ground. The most violent tornadoes are capable of tremendous destruction with wind speeds of up to 300 mph. They can destroy large buildings, uproot trees and hurl vehicles hundreds of yards. They can also drive straw into trees.
Earthquake is a term used to describe both sudden slip on a fault, and the resulting ground shaking and radiated seismic energy caused by the slip, or by volcanic or magmatic activity, or other sudden stress changes in the earth.
A flood is an overflow of water that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are an area of study of the discipline hydrology and are of significant concern in agriculture, civil engineering and public health.
Wildfires are fires that burn out of control in a natural area, like a forest, grassland, or prairie. They often begin unnoticed. They spread quickly, and can damage natural resources, destroy homes, and threaten the safety of the public and firefighters. Humans cause most wildfires.
Answer: One difference is that eukaryotic cells have a membrane-bound nucleus and prokaryotic cells do not. Another difference is that eukaryotic cells have many membrane-bound organelles while prokaryotic cells have no membrane-bound organelles.
Hope this helps! :)
Answer:
Neurons are similar to other cells because neurons have a cell membrane, a nucleus, cytoplasm, mitochondria, organelles, and carry out processes such as energy production.
Neurons differ from other cells because neurons have extensions called axons and dendrites, they communicate with each other through an electrochemical process which we just talked about, and neurons have specialized structures such as synapses and chemicals such as neurotransmitters.
Explanation:
there you go
Earth’s thin, rocky outer layer is its crust. A small example is like a crust on a piece of bread. :)
C is your answer
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.
