U3: 21- Non-Specific Body Defences Flashcards
What name is given to a microorganism that is harmful to the body/can cause disease?
Pathogen
Name three things that could be classed as pathogens.
Bacteria, virus, fungus
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 1st and 2nd lines of defence
Which line of defence in the body is specific?
The 3rd line of defence
Name the physical barrier we all have to try and keep pathogens from entering the body.
Skin (epithelial cells in the 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 trachea that traps microbes.
Mucus
Name the hairs in the trachea 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 line of defence is the inflammatory response?
2nd
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 release?
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 the 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 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 bacteria trapped in the vacuole during phagocytosis?
Pus
