The answer is enzymes. Chemicals are organic atoms that go about as impetuses and help complex responses happen wherever in life. Suppose you ate a bit of meat. Proteases would go to work and help separate the peptide securities between the amino acids.
-" infections, usually those caused by a virus (e.g. colds or flu)
allergens, most commonly from house dust mites, pets or pollen
exercise, especially in cold weather
emotions, such as excitement, fear or anger
irritants, such as air pollution
smoking people with asthma and the parents of asthmatic children should avoid smoking
changes in the weather (e.g. a cold spell)
food additives, such as tartrazine (an artificial food colouring), or food allergens, such as peanuts (sensitised or allergic individuals can have a very severe allergic reaction).
certain medications some people may be allergic to some drugs (e.g. aspirin"
