Answer:
Mars could have life.
Explanation:
This is because it is at a temperature that could sustain life. Also, bacteria has been found from Mars.
Answer: B. They are a first line of defense that can begin killing pathogens immediately.
Explanation:
B-lymphocytes are not the first line of defense. On the contrary, innate immune cells such as basophils, dendritic cells, eosinophils, Langerhans cells, mast cells are the body's first line of defence.
Answer:
Explanation:
Scientists at the Mauna Loa observatory in Hawaii say that CO2 levels in the atmosphere now stand at 387 parts per million (ppm), up almost 40% since the industrial revolution and the highest for at least the last 650,000 years.
