Genetics EXAM 1

Genetics

the study of heredity, how inherited variation is encoded, replicated, and expressed, and how it evolves over time.

Genome

Complete set of genetic instructions for any organism. It encompasses all of an organism's genes and non-coding sequences of DNA.

transmission genetics

Field of genetics that encompasses the basic principles of heredity and how traits are passed from one generation to the next and addresses the relation between chromosomes and heredity, the arrangement of genes on chromosomes, and gene mapping

molecular genetics

Study of the chemical nature of genetic information and how it is encoded, replicated, and expressed. The focus in molecular genetics is the gene and its structure, organization, and function.

Population genetics

Study of the genetic composition of populations and how that composition changes geographically and with the passage of time.The focus of population genetics is the group of genes found in a population.

model genetic organism  

An organism that is widely used in genetic research because it has characteristics, such as short generation time and large numbers of progeny, that make it particularly useful for genetic analysis.

pangenesis

Early concept of heredity proposing that particles (gemmules) carry genetic information from different parts of the body to the reproductive organs.

inheritance of acquired characteristics 

Early notion of inheritance proposing that acquired traits are passed on to offspring. Jean-Baptiste Lamarck (1744–1829)

Preformationism

Early concept of inheritance proposing that a miniature adult (homunculus) resides in either the egg or the sperm and increases in size in development, and that all traits are inherited from the parent that contributes the homunculus.

Blending inheritance

 Early concept of heredity proposing that the traits of offspring are a blend, or mixture, of parental traits.

cell theory

Theory stating that all life is composed of cells, that cells arise only from preexisting cells, and that the cell is the fundamental unit of structure and function in living organisms.

germ-plasm theory

Theory stating that cells in the reproductive organs carry a complete set of genetic information

Prokaryote

Unicellular organism with a relatively simple cell structure. Prokaryotes include bacteria (eubacteria) and archaea.

eukaryote

One of the three primary divisions of life; an organism that has a compartmentalized cell structure, including a nuclear envelope and membrane-bounded organelles. Eukaryotes may be unicellular or multicellular.

nucleus

Compartment in eukaryotic cells that is enclosed by the nuclear membrane and contains the genetic material.

histone

Low-molecular-weight protein found in eukaryotes that associates closely with DNA to form chromosomes.