Answer:
Do u still need the answer?
Explanation:
Answer:
I would say c because, sure the polar bears can swim and other things there will be very little ice once the ecosystem melts.
Explanation:
common sence
Answer:
it illustrated natural selection because the most favorable traits live longer than the unfavorable traits.
Explanation:
Answer:
I shall oppose to this notion
personally I think that since there no oxygen on mars the extraterrestrial creatures or alien plants may have alternative means of survival even if there ain't water
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.