♥ They make use of a control group because its something that they can look into, something to compare to. <span />
A. <span>Exposure to an antigen
Exposure to viruses and antigens led to the foundation of modern vaccination. Vaccination introduces an antigenic material that helps the ability of the immune system to adapt a specific pathogen, therefore leading to a long-term immunity.</span>
Answer:
Diarthroses are freely movable joints.
Explanation:
Rheumatology may be defined as the branch of medicine that mainly deals with therapy and diagnosis of the rheumatic disease. The individual specialized in this field is known as rheumatologist.
Diarthroses joint is also known as synovial joint and lined in continuous with the periosteum of the joined bones. The synovial fluid is filled in the synovial joint. The synovial joints provide the free movable joints that allow abduction, extension and adduction of the body parts.
Thus, the correct answer is option (d).
Where organisms are better adapted to their environments tend to survive and produce more kids!