Answer:
Jonas Salk was awarded the Nobel Prize for discovering a way to vaccinate against polio in the United States in the 1950's. This allowed millions of school-age children to avoid crippling disease, and to swim during summer again, as polio was often spread in public swimming areas before.
The statement that best describes how the polio vaccine works is:
It triggers the immune system to produce antobodies to fight the disease-causing agent.
Explanation:
There are two main reasons for this answer. The first one is that every vaccine is aimed to introduce a controlled amount of antigenes to be accepted by the organism. These antigens are made after some studies were conducted in a lab and were obtained from substances that the human body can accept to train the immune system to develop an effective defense for the virus or bacteria on the matter. In our case, the polio vaccine works the same way and allowed to save many lives.
Answer::-
B. Water and nutrients absorbed by roots to the stem and leaves.
Xylem constitutes of the complex tissues and plays the role of conducting tissue for water and minerals from root to the stem and leaves (shoot).
Answer: wherever the wind blows :)
Explantation: the waves go 90 degrees to the left (southern hemisphere) or the right (northern hemisphere)
also, if it's blowing away from the beach, it causes upwelling,
which brings nutrients from the bottom of the ocean and attracts more organisms.
hope this helps :)
Answer:
Water flowing in rivers and streams
Explanation:
Gravity causes precipitation to fall from clouds and water to flow downward on the land through watersheds.
