Toxicology and Dose Importance Quiz

It is an important factor in toxicology and can be summarized by the principle 'the dose makes the poison.'

LD50 refers to the dose of a substance that displays toxicity by killing 50% of a test population.

LD50 measures the lethal dose of a substance, while LC50 measures the lethal concentration of a substance.

<p>Studying toxicology helps protect from the toxic effects of toxicants.</p> Signup and view all the answers

<p>Analytical toxicology is important for identifying and measuring toxic substances in biological samples.</p> Signup and view all the answers

<p>Studying toxicology leads to the development of innovative drug therapies with reduced toxicity to the human body.</p> Signup and view all the answers

<p>Chronic toxicity involves long-term exposure at lower doses for more than 3 months, while subchronic toxicity involves intermediate duration exposure at higher doses for a few weeks to 3 months.</p> Signup and view all the answers

<p>One example is cirrhosis in alcoholics who have ingested ethanol for several years.</p> Signup and view all the answers

<p>The two stages are initiation, where a normal cell undergoes irreversible changes, and promotion, where initiated cells are stimulated to progress to cancer.</p> Signup and view all the answers

<p>Subchronic toxicity involves repeated exposure at higher doses than acute toxicity studies but for a shorter duration.</p> Signup and view all the answers

<p>LD50 refers to the lethal dose that causes death in 50% of the population, while LC50 is the lethal concentration that causes death in 50% of the population.</p> Signup and view all the answers

<p>Studying chronic toxicity is important as it represents cumulative damage over time to specific organ systems, leading to recognizable clinical diseases.</p> Signup and view all the answers

<p>Local effects occur at the site of first contact between the biological system and the toxicant. For example, ingestion of caustic substances or inhalation of irritant materials.</p> Signup and view all the answers

<p>Systemic effects require absorption and distribution of a toxicant to a distant site, where deleterious effects are produced.</p> Signup and view all the answers

<p>Target organs are the specific organs where a chemical elicits its major toxicity.</p> Signup and view all the answers

<p>Local toxicity occurs at the site of first contact, while systemic toxicity involves distribution to distant sites.</p> Signup and view all the answers

<p>LD50 represents the dose of a toxicant that is lethal for 50% of the population tested.</p> Signup and view all the answers

<p>Additive effects occur when the combined effect of two chemicals equals the sum of their individual effects, while synergistic effects result in a combined effect greater than the sum of individual effects.</p> Signup and view all the answers