Infectious Diseases

Question 1

Describe specific/adaptive immune system

Answer 1

Relies on T & B cells (lymphocytes)

Antigen (protein or carb) is on pathogen surface/toxin

Antigen or epitope(accessible part) -> binds to complementary antigen receptor on T/B cell

Question 2

Describe non-specific/innate immune system

Answer 2

Physical barriers, chemical/proteins/immune cells
(mucus, cilliated epithelial cells, acidic stomach environment)

1) Phagocytosis by diff cells -> detect components w Toll like receptors
2) Fuse w primary lysozyme w hydrolytic enzymes

ANTIMICROBIAL PROTEINS
A) Interferons -> subset of cytokines
innate defence by interfering w viral infections
Virus infected cells secrete interferons -> induce nearby healthy cells to expresss antiviral genes

B) Complement system
Diff complement proteins assemble into bacterial membrane to form membrane attack complex (MAC)
-> promote recognition of bacteria by phagocytes -> phagocytosis

Inflammatory response
1) Mast cells -> produce histamine -> triggers dilation of blood vessels, increase permeability to antimicrobial proetins & phagocytes
2) Macrophages secrete cytokines -> dilates blood vessels
3) Attract neutrophils -> engulf & ingest pathogens
4) Response is activated complement proteins

Question 3

Describe active immunity

Answer 3

Consists of B cells & T cells (lymphocytes)
Have antigen receptors cell surface protein
Specific antigen recpetor complementary in shape & binds to specific antigen
(to 1 part of molecule of pathogen)
-> Epitope (accessible portion to antigen receptor)

Question 4

Describe naturally acquired immunity

Question 4

Describe passive immunity

Question 5

Describe artificially acquired immunity

Question 6

Outline roles of B lymphocytes, T lymphocytes, antigen presenting cells & memory cells in primary & secondary response

Question 7

Explain r/s of molecular structure of antibodies to their functions, w Immunoglobulin G (igG)

Question 8

Explain how
1) somatic recombination
2) Hyper-mutation
3) class switching
-> leads to diff antibody moleq

Question 9

How can vaccination control disease? (smallpox)
+ Herd immunity to break disease transmission cycle

Question 10

Benefits of vaccination

Answer 10

1. Confers immunity to pathogen not exposed to before
2. Life long immunity -> Production if B & T cells
3. Herd immunity, disrupt disease infection cycle
4. Cost effective
5. Can prevent certain types of cancer
6. Protects against related diseases
7. Reduce prevalence of antibiotic resistant bacteria
8. Safe travel, reduce spread

Question 11

Risks of Vaccination

Answer 11

Rare severe allergic reaction

Live attenuated viruses fan regain virulence

Question 12

How does influenza cause disease

Question 13

How does HIV cause disease

Question 14

Explain transmission of bacteria (Tuberculosis)

Question 15

Describe mode of action of antibiotics & penicillin