answer is antibodies.
B cells are a type of lymphocytes and it is responsible for the immune system. B cells help to protect body by producing specific antibodies to fight against each antigen which are strangers to the body specially for viral infections.
<h3>Global travel and spread of certain species</h3>
Explanation:
Many pathogenic species of bacteria, virus, and other microbes are more prevalent in developing or tropical countries rather than in developed countries.
When an individual’s immune system is weak they become more susceptible to get infected and become carriers of that particular species.
The species grows, develops, and multiplies in the host’s body and when the traveler travels to his/her home country or any other place he/she can transmit the disease to others and again the species grows in numbers. Higher the rate of spread of infection higher is the increase in species.
It is called peristalsis movement.
You can further understand a text if you ask questions.
Phagocytosis is the process by which immune cells engulf and then destroy bacteria
