The control group in this experiment is the group of tomatoes that do not receive any fertilizers i.e. fourth tomato plants.
<h3>What is Fertilizer?</h3>
Fertilizer may be defined as any chemical or natural substance which is added to the soil with the intention of enhancing productivity.
All those groups of tomatoes in which fertilizers are added behave as a reference group while those in which fertilizer is not added behave as a control group.
Therefore, it is well described above.
To learn more about Fertilizers, refer to the link:
brainly.com/question/24544067
#SPJ1
Answer:
Adaptive immune defense system consists of lymphocytes like B-lymphocytes and T- lymphocytes. B-lymphocytes provides humoral immunity while T- lymphocytes provide cell-mediated immunity to the body.
99% of lymphocytes circulate freely in the blood and lymph. B lymphocytes differentiate into plasma B cells and B memory cells when interact with antigen presented by T helper cells.
Then plasma cells secrete antibodies in the circulation which binds to extracellular antigens through antigen-binding site. Then the bounded antigen is recognized by receptors present on phagocytic cells. This receptor binds the Fc region of antigen bounded antibody and destroy the antigen by phagocytosis.
The best answer is nitrogen.<span> After all, it is found in our nucleic acids and proteins. </span>Calcium can be found abundantly in our bones since calcium makes our bones strong. Sulfur can be found in our body but only in low and insignificant amounts. Boron is said to be lethal when taken in great amounts in our body; it can cause diseases and illnesses.
