Pathogens

What are Pathogens?

An organism or agents that are able to cause disease

Viruses are particles of:

1. nucleic acid (DNA or RNA)

2. a protein coat called capsid

3. lipid coating (in some cases)

Pathogens are not..

They are not made up of cells

How do they replicate?

Replicate by infecting living cells - require a host

Vaccine definition

Injections that contain weakened/ killed pathogens. Stimulate immune system &prompt body to produce antibodies

Antibiotics Definition

Compounds that block the growth and reproduction of bacteria.

Bacteria properties

• unicellular

• can be harmless or beneficial

• microscopic

• often infects just one part of the body

• can be treated using antibiotics

Viruses properties

• acellular

• submicroscopic

• takes over your own cells in order to make more of itself

• may be prevented using vaccines

Defence against disease - Barriers

• skin (1st Line of defence)

• mucus

• stomach acid, tears and saliva

Post infection defense

1. some white blood cells can ingest foreign invaders (antigens)

2. other types of white blood cells release antibodies that attack antigens. Clone rapidly

3. Some will remain in your blood as “memory cells” and can attack more quickly the next time you encounter the same antigen.

Non - Infectious disease

Disease that is not contagious (cannot be spread)

Infectious disease

Contagious disease (can be spread)

Contagious

can be spread through direct or in direct contact

Infected

Someone who has a illness or disease