Question

Imagine you are a pathogen. You are trying to invade a human, and you find yourself moving through barriers. Describe the barriers you face (the components of the immune system), how you move past these barriers and their response to you (immune responses). Include how this invasion would be easier if the human had a weakened immune system.

Answer 1

This explanation covered most of the points..

If I was a pathogen i would have to get past many barriers in order to infect the intended human. Barriers such as Physical barriers, chemical barriers, and biological barriers. A few examples of these would be, skin, saliva, mucus, and sneezing. However, if i were to get past all these barriers, i would still have to deal with problems inside the body such as the humans immune system and its special cells. An example would be the langerhans cells which are found in the dermis of the skin. These cells are responsible for identifying foreign material and carrying them to the lymph nodes for destruction which would be where i would be taken. However, if the humans body had a weak immune system or disorders such as an immunodeficiency, it would make it easier for me to infect the body. The reasons it would be easier is because when the body has an immune system disorder it decreases the production of antibodies, which can help fight me off, their body is more easily exposed to disease, immune cells mistake healthy cells as pathogens and abnormal cells will crowd out the healthy cells and steal nutrients from them.

Answer 2

The different barriers that you have to go through are the different organs of the immune system. These are the lymphoid organs, thymus, and bone marrow. The secondary wall that you have to go through are the lymphatic tissues which include the lymph nodes, adenoids, skin, liver, tonsils, spleen, and the lymph vessels.

At all times, these systems work hand-in-hand so that the body can protect itself in order for it to survive