history and terminologies Flashcards
Genetics- derived from the Greek word gen,
meaning
become or to grow something
. It is the branch of biology that deals with the
principles of heredity and variation in all living things; the study of genes
genetics
1860s Mendel’s work on peas allows the
conclusion that traits are inherited through discrete units passed from one generation to the next
describes nucleic acids
Friedrich Miescher
1909 The word ‘gene’ coined by Danish botanist
Wilhelm Johannsen
1910 Thomas Morgan’s work on fruit flies
demonstrates that genes
lie on chromosomes
she describes mobile genetic elements in maize
1940s Barbara McClintock
shows in bacteria that nucleic acids are the ‘transforming principle’
1944 Oswald Avery
they publish the double helix model for DNA’s chemical structure
1953 James Watson and Francis Crick
they find that protein-coding genes are carried in segments
1977 Phillip Sharp and Richard Roberts
the progeny inherits any characteristic as the average of the parents’ values of that characteristic
Blending Inheritance (Early 1800s
by Aristotle; every part of the body emits tiny particles (gemmules) which migrate to the gonads & are transferred to the offspring; implied that changes to the body during an organism’s life would be inherited
Theory of Pangenesis/Preformation (19th Century)
– first challenged the Theory of Pangenesis and proposed Germplasm Theory
August Weismann (1834-1914
sex cells perpetuated themselves in reproduction generation after generation; inheritance takes place by means of sex cells
Germplasm Theory
refers to the observable characteristics or traits of an organism that are produced by the interaction of the genotype and the environment (e.g. appearance. Also the physical expression of one or more genes
Phenotype
physical location of a gene on a chromosome. It is the particular neighborhood where the gene is found;
locus
the offspring resulting from combining the qualities of two organisms of different varieties, species or genera through sexual reproduction
hybrid
a person who can pass an inherited (genetic) disease on to their children but who does not have the disease. He/she have a variant related to a disease within your genetic material
carrier
– an organism or a new genetic character arising or resulting from mutation, which is genetically an alteration of the DNA sequence of the genome or chromosome of an organism
mutant
– the gene, characteristic, or phenotype that occurs most frequently in the natural population
wild type
the mating of an organism whose genetic constitution is unknown with an organism whose entire genetic makeup for a trait is known, to determine which genes are carried by the former.
test cross
the mating of a hybrid organism with one of its parents or with an organism genetically similar to the parent.
back cross
the fusion of male and female gametes produced by the same individual. Also called autogamy
Self-fertilization
the parents w/ a particular phenotype produce offspring only w/ the same phenotype.
trueee breeding
a systematic listing (either as words or as
symbols) of the ancestors of a given
individual, or it may be the “family tree” for a
large number of individuals
pedigree analysis
are placed in birth order from left to right and
are labeled with Arabic numerals. all offspring
sibs
a male whose phenotype drew
the attention of a physician or geneticis
propositus
a female of the same
circumstance
porposita
– individual whose phenotype drew
the attention to the family
proband
