Defense Against Infectious Diseases

This blog post is going to be a little different from the ones I've made before. After all, the blog is for my personal use and I want to make it more engaging for me. Therefore this post will be more concise, and I will use bullet points answering the IB Assessment Statements to do so.

1.Pathogens-Any living organism or virus that is capable of causing a disease. They include viruses, bacteria, protozoa, fungi, and worms of various types.

2.Antibiotics-Chemicals that take advantage of the differences between prokaryotic and eukariotic cells.

• many types: some selectively block protein synthase while others inhibit the production of new cells
• antibiotics damage or kill PROKARYOTIC cells, but not eukaryotic cells and their metabolism

*Viruses use our own cells' metabolism to creat

e new viruses. Thus, they "hide" in our own cells using them as host cells, and that's why antibiotics don't work against viruses.

3. *Skin: Barrier to infection

• dermis:contains sweat glands, capillaries, sensory receptors, and dermal cells. They give structure and strength to skin.
• epidermis:(dead cells) not truly alive and they are intact= protected from most pathogens

*Mucus:(trachea, nasal passages, urethra, vagina)

• cells produce and secrete lining of mucus
• trap incoming pathogens
• some lined with CILIA-hair like extensions
• lysosyme-enzyme that damage pathogens

4.Phagocytic Leukocytes (WBC)

• Macrophages-large WBC that are able to change their cellular shape to surround an invader and take it in through the process of PHYGOCYTOSIS
• engulf pathogen- just like lysosomes in cell
  
  

5. Antigens vs Antibodies

• antigens-molecules that our immune system considers to be "not-safe"
• antibodies-protein molecules that we produce in response to specific types of pathogens

6.Antibody production

• specific immune response
• pathogen enters body
• macrophage engulf pathogens
• pieces of pathogen become part of macrophage's membrane
• antigen presentation=lymphocytes T recognize pieces=are activated
• T cells activate specific B cells-they divide (by cloning) and form:

-plasma cells=secrete antibodies that bind to antigens

-memory cells-stay in circulation

7.Effects of HIV on immune system

• HIV (human immunodeficiency virus)-results in the set of symptoms called AIDS
• reverse transcriptase (enzyme) enables genetic info. of HIV to become integrated permanently into genome of host cell
• infects helper T cells- disables them=no antibody production=body doesn't fight pathogens as it used to before

8. AIDS

• caused by HIV
• transmition: person to person by body fluids (blood transfusions/ sex/ etc)
• social implications: discrimination against infected people=labeled as homosexuals/drug abusers/ hard time finding jobs/ etc.
• its a virus=immune to vaccine (hides away in host cells)