antibodies activate the complement system. a complement system consists of a number of small proteins found in the blood. when an antigen attacks the body, the body responds by producing antibody to that antigen. antibody binds to antigen forming an antibody antigen complex. this complex has the ability to activate compliment system. the end result of activation of compliment system is activation of phagocytes that attack foreign cells in the body. activation of compliment also stimulates inflammation that leads to attraction of more phagocytes.
Homeostasis is the process of maintaining a constant internal environment.
False only self pollinating plants can do that they can cross pollinate and mate with each other
Answer:
arteries carry blood away from the heart and veins carry blood to the heart
The correct answer is option D. Prophase I
The crossing over is a phenomena, which occur in the cells undergoing meiosis. In the process of crossing over, the exchange of the genetic material takes place between the sister chromatids. This process takes place in the prophase 1 stage of meiosis 1 in the gametes. The exchange of genetic material between chromatids cause recombination, and hence, genetic variation.