Today I’m going to talk about: Poison
I’ve divided my presentation into two parts:
First I’d like to introduce the poison and second I’ll present of same
kinds of poison.
So, let’s start with introduce
Poison, any substance that produces disease conditions, tissue injury,
or otherwise interrupts natural life processes when in contact with or
absorbed into the body. Most poisons taken in sufficient quantity are
lethal. A poisonous substance may originate as a mineral, vegetable, or an
animal, and it may assume the form of a solid, liquid, oor gas. A poison,
depending on the type, may attack the surface of the body or, more
seriously, internal organs or the central nervous system.
Finally let’s consider: with kinds of poison
Poisons in humans are usually classified according to their effects as
corrosives, irritants, or narcotics; the last named are also known as
systemic or nerve poisons.
Corrosives include strong acids or alkalis that cause local tissue
destruction, externally or internally; that is, they “burn” the skin or the
lining of the stomach. Common or so-called household corrosive ppoisons
include hydrochloric acid, carbolic acid, bichloride of mercury, and
Irritants such as arsenic, mercury, iodine, and laxatives act directly
on the mucous membrane, causing gastrointestinal irritation or inflammation
accompanied by pain and vomiting; diluted corrosive poisons also have these
effects. Irritants include cumulative poisons, th
absorbed gradually without apparent harm until they suddenly take effect.
Narcotic poisons act upon the central nervous system or upon important
organs such as the heart, liver, lungs, or kidneys until they affect the
respiratory and circulatory systems. These poisons can cause coma,
convulsions, or delirium. Narcotic poisons include alcohol, opium and its
derivatives, belladonna, turpentine, potassium cyanide, chloroform, and
strychnine. Also included in this category is one of the most dangerous
poisons known, botulin toxin, a potent bacterial toxin that is the cause of
acute food poisoning (see Botulism).
Blood poisoning, also bacterial in nature, is a condition that occurs
when virulent microorganisms invade the bloodstream through a wound or an
infection. Symptoms include chills, fever, prostration, and often
infections or secondary abscesses in various organs (see SSepticemia). Most
poison gases also affect the bloodstream. Because these gases restrict the
body’s ability to absorb oxygen, they are often considered in a separate
category called asphyxiants, to which group ordinary carbon monoxide
belongs. Gas poisons, however, may also be corrosives or irritants