Answer: Option B
Explanation: The first line of defense acts a barrier and does not allows the foreign materials to enter inside the body. It includes chemical and physical barriers that are always ready to protect the body from infection.
Example: Skin and mucous membrane.
Skin is largest organ and it acts as a barrier between pathogens and human body. It acts a waterproof material and the pathogens cannot get inside through skin unless the skin is broken.
Mucous membranes also acts as first line of defense and breaks the cell wall of many bacteria entering through the openings of the body.
So, skin and mucous membrane are the first line of defense.
Answer:
nitrogen can be changed into macromolecules like proteins and nucleic acids (DNA and RNA)
Explanation:
For divergent boundary: when the crust of the earth fractures it allows magma to reach the surface. For convergent boundary: When one of the converging plates move underneath the other, a process also known as subduction; the new magma rises and can erupt to form volcanos. For the Hotspot: magma pushes through cracks in the crust to form volcanos. Hope this helps!!
The answer is B) change the rate of reaction