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chlorophyll

(Encyclopedia)CE5 chlorophyll klôrˈəfĭlˌ [key], green pigment that gives most plants their color and enables them to carry on the process of photosynthesis. Chemically, chlorophyll has several similar forms...

fever

(Encyclopedia)fever, elevation of body temperature above the normal level, which in humans is about 98℉ (37℃) when measured orally. Fever is considered to be a symptom of a disorder rather than a disease in its...

protoplasm

(Encyclopedia)protoplasm, term once used for the fundamental material of which all living things were thought to be composed. It was studied by a number of early scientists, especially by Félix Dujardin, J. E. Pur...

frozen foods

(Encyclopedia)frozen foods, products of the food preservation process of freezing. This process has been employed by people in the Arctic from prehistoric times. Eskimos throw fresh-caught fish on the ice to freeze...

snakebite

(Encyclopedia)snakebite, wound inflicted by the teeth of a snake. The bite of a nonvenomous snake is rarely serious. Venomous snakes have fangs, hollow teeth through which poison is injected into a victim. All type...

Annelida

(Encyclopedia)CE5 A. The earthworm, Lumbricus terrestris, representative of the phylum Annelida. B. Internal anatomy of an earthworm. Annelida ənĕlˈĭdə [key] [Lat., anellus=a ring], phylum of soft-bodied, ...

Ptolemy

(Encyclopedia)Ptolemy (Claudius Ptolemaeus), fl. 2d cent. a.d., celebrated Greco-Egyptian mathematician, astronomer, and geographer. He made his observations in Alexandria and was the last great astronomer of ancie...

Highlands

(Encyclopedia)Highlands, mountain region in the northern extremity of Scotland. It consists roughly of the Scottish area north of the imaginary line from Dumbarton to Stonehaven excluding the Orkneys, the Shetlands...

norepinephrine

(Encyclopedia)norepinephrine nôrˌĕpīnĕfˈrən [key], a neurotransmitter in the catecholamine family that mediates chemical communication in the sympathetic nervous system, a branch of the autonomic nervous sys...

nursery

(Encyclopedia)nursery, in horticulture, an establishment or area for the propagation, breeding, and early cultivation of plants. In North America the term nursery originally specified a place where hardy woody plan...