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Defence Against Disease
Transcript of Defence Against Disease
Let us explore the body and the basics of how it protects against disease!
The main physical barriers include...
The body's defence against disease begins with the body's basic physical barriers
Cells fit tightly together to form a protective layer covered by dead cells
The Mucous Membranes
When unbroken, skin prevents the entry of pathogens
These are cells lining the respiratory tract and openings of the urinary and reproductive systems that secrete a protective layer of mucus
Mucus is sticky and traps pathogens and other particles. When there are many pathogens more mucus is produced to flush them out
For example, the mucus in your mouth is produced to trap any foreign particles and then you spit them out!
Cilia are hair like projections from cells lining air passages
For defence against diseases, they appear in the trachea (windpipe) to sweep mucus and dirt out of the lungs to the throat
Chemical barriers in the body include chemicals in the stomach, tears and many other parts of the body
Chemicals in the stomach is alkaline and destroys pathogens that may be resistant to acid or pathogens that have been carried by cilia to the throat and swallowed
Pores in the skin secrete sweat with chemicals that kill bacteria
We will take a deeper look at these physical barriers
An introduction to the immune system...