Glossary | T

Tactile
pertaining to the sense of touch
Taxonomy
science of classifying organisms in established categories according to their biological and evolutionary characteristics; nomenclature is usually Greek or Latin in derivation
Temperate zone
moderate temperature area located between the polar and tropical zones
Tentacles
long, cylindrical projections from an organism, specialized as sensory, grasping and food collecting structure
Terrestrial
pertaining to plant or animal life on land rather than in water
Territory
area with defined boundaries established and defended by an animal, usually for breeding and/or foraging
Test
shell or casing of an organism. Skeleton of a sea urchin.
Tetrapod
animals that are four-limbed (two pairs): includes amphibians, reptiles, birds, mammals
Tetrodotoxin
neurotoxin that acts specifically on nerve cells, commonly causing paralysis, especially tetrodotoxin, bactrachotoxin, and compounds found in the toxins of some bees, scorpions, and spiders
Thermocline
water layer in which temperature changes rapidly with increasing depth
Thorax
portion of the body between the head and abdomen; the chest region
Tide
periodic rise and fall of oceanic water levels (usually twice daily) along a shore caused by the unequal gravitational pull of the sun and moon on different parts of the rotating earth
Tide pool
pool of water left along the shore as the tide level falls
Tidemark
high water mark left by tidal water
Toxin
any substance harmful to living cells
Trophic
pertaining to growth or nutrition
Tube feet
extension of the water vascular system of echinoderms (sea stars, sea urchins, etc.) that aids in locomotion, grasping and feeding
Turbid
stirred up sediment; cloudy
Turf
thick mat of plants and animals on a substrate