SLCC ENSC 1000 Exam 2 Questions with 100% Correct Answers | Latest Update | Verified

6 components of soil - -sand and gravel -silts and clays -dead organic material -soil fauna and flora -water -air A horizon (surface soil) - Mineral particles mixed with organic material. Food comes from the A horizon. A pattern of falling death and birth rates due to improved living conditions including education for women and access to birth control methods? - demographic transition Acute Effects - caused by a single exposure and results in an immediate health problem Additive Reaction - effects of two chemical occurring together are added to one another Allergens - substances that activate the immune system Anesthetics and Chlorinated Hydrocarbons - disrupt nerve cell membranes Antagonistic Reaction - one material interferes with the effects, or stimulates the breakdown, of other chemicals Antibiotics - chemicals that kill or inhibit the growth of bacteria Antibodies - proteins produced by our bodies that recognize and bind to foreign cells or chemicalsAntigens - substances that are recognized as foreign by white blood cells and stimulate the production of specific antibodies Arable land - land suitable for growing crops B Horizon (Subsoil) - Often dense texture due to clays Bioaccumulation - selective absorption and storage of toxins Biological Pests - organisms such as insects or fungi that compete with humans to consume agricultural crops. Biomagnification - Toxic burden of a large number of organisms at a lower trophic level is accumulated and concentrated by a predator at a higher trophic level. Example: DDT C Horizon - Weathered rock fragments with little organic material Carcinogens - substances that cause cancer Chemicals are divided into two major groups - those that dissolve more readily in water those that dissolve more readily in oil Chlorinated Hydrocarbons - pesticide type that is fast acting and highly toxic to sensitive organisms Chronic Effects - Long-lasting, perhaps permanent. Can be result of single large dose or repeated smaller doses. Clearcutting - the removal of all trees in a standContour Plowing - plowing across slope to slow flow of water