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moss, in botany

(Encyclopedia)CE5 Life cycle of a moss: A germinating spore forms a transitory branching structure on the soil surface, which develops into the conspicuous gametophyte, the familiar moss plant. Eggs and sperm ar...

snake, in zoology

(Encyclopedia)snake, common name for an elongated, limbless reptile of the order Squamata, which also includes the xlizards. Most snakes live on the ground, but some are burrowers, arboreal, or aquatic; one group i...

ray, in zoology

(Encyclopedia)ray, extremely flat-bodied cartilaginous marine fish, related to the shark. The pectoral fins of most rays are developed into broad, flat, winglike appendages, attached all along the sides of the head...

In

(Encyclopedia)In, symbol for the element indium. ...

clone

(Encyclopedia)clone, group of organisms, all of which are descended from a single individual through asexual reproduction, as in a pure cell culture of bacteria. Except for changes in the hereditary material that c...

genetic testing

(Encyclopedia)genetic testing, medical screening for genetic disorders, by examining either a person's DNA directly or a person's biochemistry or chromosomes for indirect evidence. Testing may be done to identify a...

fish, in zoology

(Encyclopedia)CE5 Anatomy of a ray-finned fish fish, limbless aquatic vertebrate animal with fins and internal gills. Traditionally the living fish have been divided into three class: the primitive jawless fish...

eugenics

(Encyclopedia)eugenics yo͞ojĕnˈĭks [key], study of human genetics and of methods to improve the inherited characteristics, physical and mental, of the human race. Efforts to improve the human race through bette...

reproductive system

(Encyclopedia)CE5 Reproductive system reproductive system, in animals, the anatomical organs concerned with production of offspring. In humans and other mammals the female reproductive system produces the femal...

infertility

(Encyclopedia)infertility, inability to conceive or carry a child to delivery. The term is usually limited to situations where the couple has had intercourse regularly for one year without using birth control. The ...