Answer:
The immune response is how your body recognizes and defends itself against bacteria, viruses, and substances that appear foreign and harmful.
Information
The immune system protects the body from possibly harmful substances by recognizing and responding to antigens. Antigens are substances (usually proteins) on the surface of cells, viruses, fungi, or bacteria. Nonliving substances such as toxins, chemicals, drugs, and foreign particles (such as a splinter) can also be antigens. The immune system recognizes and destroys, or tries to destroy, substances that contain antigens.
Your body's cells have proteins that are antigens. These include a group of antigens called HLA antigens. Your immune system learns to see these antigens as normal and usually does not react against them.
No they can't move themselves but rather transported
The difference between tobacco and smokeless tobacco is that the smokeless tobacco is something you could chew onto and causes more risk of a heart attack then by smoking tobacco. Tobacco is also dangerous and you would call it secondhand smoking since it’s nothing chewable. And simply just smoking tobacco from 1 to 7 hours could increase a heart attack risk by 24%.
Although peer pressure can influence adolescents’ alcohol use, individual susceptibility to these pressures varies across individuals. The dopamine receptor D4 gene (DRD4<span>) is a potential candidate gene that may influence adolescents’ susceptibility to their peer environment due to the role dopamine plays in reward sensation during social interaction. We hypothesized that </span>DRD4<span> genotype status would moderate the impact of 7th-grade antisocial peer pressure on 12th-grade lifetime alcohol use (</span>n<span> = 414; 58.7 % female; 92.8 % White). The results revealed significant main effects for antisocial peer pressure, but no main effects for</span>DRD4<span> genotype on lifetime alcohol use. Adolescent </span>DRD4<span> genotype moderated the association between peer pressure and lifetime alcohol use. For individuals who carried at least one copy of the </span>DRD4<span> 7-repeat allele (7+), antisocial peer pressure was associated with increased lifetime alcohol use. These findings indicate that genetic sensitivity to peer pressure confers increased alcohol use in late adolescence.</span>