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Found Class 157 times.

Displaying results 1 to 10.

1. Acanthocephala (spiny-headed worms)
A phylum of parasitic organisms, from one of three general classes, generally referred to as spiny-headed worms. They are notable for their lack of a digestive tract.

2. Acesulfames
A class of artificial sweeteners derived from oxathiazinone; some varieties are over a hundred times sweeter than table sugar ( sucrose ).

3. Acoelomate
A triploblastic organism which does not have an internal body cavity other than the gut. The area between the gut and the organism's outer body wall is completely filled with tissue derived from the mesoderm . The term is used to classify multicellular animals by developmental pattern.

4. Adverse effect
This is an abnormal or harmful effect to an organism caused by exposure to a chemical. It is indicated by some result such as death, a change in food or water consumption, altered body and organ weights, altered enzyme levels, or visible illness. An effect may be classed as adverse if it causes functional or anatomical damage, causes irreversible change in the homeostasis of the organism, or increases the susceptibility of the organism to other chemical or biological stress. A non-adverse effect will usually be reversed when the organism is no longer being exposed to the chemical.

5. Age-class
A group of individuals of a species that have the same age.

6. Aggregates
Fairly random associations of animals with little or no internal organization; form in response to a single stimulus and disperse when the stimulus is removed; one of the three broad classes of social organization.

7. Alcohol
Ethyl alcohol, also known as ethanol, the spirit in wine, is classified as a sedative-hypnotic drug. The criminal code of Canada states that it is an offence while the person's ability to operate or has control of a motor vehicle or vessel is impaired by alcohol or a drug or while the person's blood levels of alcohol exceed 80 mg/dL. Impaired driving performance has been observed with serum levels of ethanol as low as 30 mg/dL. A serum level above 300 mg/dL usually produces coma. Intoxication of alcohol is associated with violence, suicide, child and spouse abuse, respiratory depression, stupor, vomiting, predisposing to Mallory-Weiss Syndrome, hypoglycemia, cardiac arrhythmia, seizures. Chronic ingestion is associated with liver cirrhosis and withdrawal symptoms (Delirium Tremens).Two groups of alcohol drinkers are indentifiable based on the pattern of drinking: the problem drinkers and the ones with severe alcohol dependence. * Methyl alcohol, also known as methanol, or wood alcohol can also produce the sensation of being "drunk". However, ingestion of large quantities of methanol can cause visual disturbances (blindness via neurological damage), and a metabolic acidosis and is a medical emergency necessitating fluid resuscitation, respiratory care, ethanol infusion to block the building up of toxic products and dialysis. * Isopropyl alcohol is rubbing alcohol; it is poisonous.

8. Aldose reductase inhibitor
A class of drugs being studied as a way to prevent eye and nerve damage in people with diabetes . Aldose reductase is an enzyme that is normally present in the eye and in many other parts of the body. It helps change glucose (sugar) into a sugar alcohol called sorbitol. Too much sorbitol trapped in eye and nerve cells can damage these cells, leading to retinopathy and neuropathy . Drugs that prevent or slow (inhibit) the action of aldose reductase are being studied as a way to prevent or delay these complications of diabetes.

9. Aliphatic
A major class of organic compounds where carbon and hydrogen molecules are arranged in straight or branched chains. A type of hydrocarbon . Includes alkane s, alkene s, and alkyne s.

10. Alkaloids
A class of over 3000 known nitrogen-containing compounds (such as morphine, caffeine, cocaine and nicotine ) that are typically basic ( pH over 7) and are produced by plants but have strong physiological effects on animals (including humans). They are synthesized from amino acid precursors such as tryptophan and tyrosine .

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