U.3 K.A-5 Non-Specific Body Defences Flashcards
What name is given to any organism that can cause disease?
Pathogen
Name two things that could be classed as pathogens.
- Bacteria
- Virus
How many lines of defence are employed by the body to protect itself from pathogens?
3
Which lines of defence in the body are non-specific?
The first two lines of defence
Which line of defence in the body is specific?
The third line of defence
Name the physical barrier that we all have to try and keep pathogens from entering the body>
Skin
Name the substance produced by the stomach to kill pathogens.
Hydrochloric acid
Name the substance produced by the epithelial cells in the lining of the tracheas that traps microbes.
Mucus
Name the hairs in the tracheas that move mucus up to the top of the mouth for swallowing or spitting out.
Cilia
What is the name of the enzyme found in tears and saliva that digests bacterial cell walls?
Lysozyme
How do sweat glands in the skin kill microbes?
The sweat glands keep the skin at too low a pH for microbes to thrive
What level of defence is the inflammatory response?
Second level
When is the inflammatory response used by the body?
When it suffers a physical injury such as a cut or invasion by microorganisms
What cells are activated in the connective tissue when the body suffers an injury?
Mast cells
What do mast cells contain?
Histamine
What does histamine do to blood vessels?
Causes them to dilate and become more permeable
What name is given to the dilation of the blood vessels during the inflammatory response following the release of histamine?
Vasodilation
Which type of white blood cell is released during the inflammatory response?
Phagocytes
Name the cell-signalling molecule released by the phagocytes that attract more phagocytes to the site of injury.
Cytokines
During the inflammatory response, as well as phagocytes gathering at the site of infection or injury, what else is released to clot the blood and prevent further blood loss?
Blood-clotting chemicals
Name the process that the phagocytes carry out during the inflammatory response.
Phagocytosis
During phagocytosis what does the phagocyte move towards?
The bacteria or other pathogen that needs to be destroyed
What does the cell membrane infolding round a bacterium form during phagocytosis?
A vacuole
Name the tiny vesicles present in a phagocyte that are full of digestive bacteria.
Lysosomes
What is left when the digestive enzyme digests the bacteria trapped in the vacuole during phagocytosis?
Pus
