The answer is "D"
The body's first line of defense is also known as Innate immunity and incudes mucous membranes. Both the intact skin and mucous membranes of the body offer a high degree of protection against pathogens.
A good example is the mucous membrane of the respiratory tract. It is lined up with cilia and covered with mucus. The coordinated beating of the cilia drives the mucus up to the nose and mouth where the trapped bacteria can be expelled.
(Lymph nodes and white blood cells belong to the second line of defense, not the first)
Answer:
abiogenesis
Explanation:
a (not) biogenesis (coming from other life forms)
Biogenesis would mean that it's coming from other life forms,
Natural selection is a part of evolution (what is there to select?)
Variation is also a part of evolution (not related)
Answer:
plant leaves contain openings called stomata, which allow the diffusion of gas exchange
That would be false. A catacomb is an ancient underground cemetery.
exact meaning: an underground cemetery consisting of a subterranean gallery with recesses for tombs, as constructed by the ancient Romans.
