Answer:
It would be difficult to recreate the exact conditions of the chemical release elsewhere.
Explanation:
Active transport because it is moving from a lower concentration to a higher concentration
The primary function of all lymph nodes is the production of lymphocytes, which help defend the body against microorganisms and against harmful foreign particles and debris from lymph before it is returned to the blood stream. The major clusters of lymph nodes are in six areas.
Birds were a major widespread during this time period therefore the answer is the last option