It is soil after wind for example wind storm causes to soil erosion
Answer:
Peas exhibit a variety of contrasting traits (purple vs. white flowers; round vs. wrinkled seeds). The shape of the pea flower protected it from foreign pollen.
Explanation:
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:
Alkali metals are any of the elements found in Group IA of the periodic table (the first column). Alkali metals are very reactive chemical species that readily lose their one valence electron to form ionic compounds with nonmetals. All elements in the alkali metal group occur in nature.
Explanation:
