molecular biology intro Flashcards
It is the study of gene structure and function at molecular level.
molecular biology
Symposium on Aspects of Growth
1934
part of T.H. Morgan’s famous “fly group” that pioneered the development of the fruit fly Drosophila as a model genetic organism
Calvin Bridges
a plant geneticist, 1941, became President of the Botanical Society of Americ
James T. Buccholtz
Symposium on Nucleic Acids and Nucleoproteins
1947
an eminent biochemist, became a bitter critic of molecular biology, an occupation he described as “essentially the practice of biochemistry without a license”.
Edwin Chargaff
Symposium on Viruses
1953
both phage geneticists.
Raymond Appleyard & George Bowen
did the simple experiment that finally convinced most people that the genetic material is DNA.
Alfred Hershey and Martha Chase
Symposium on Synthesis and Structure of Macromolecules
1963
demonstrated that genes control the amino acid sequence of proteins; the mutation causing sickle-cell anemia produces a single amino acid change in the hemoglobin protein.
Vernon Ingram
was key in unraveling the genetic code, using protein synthesis directed by artificial RNA templates in vitro.
Marshall W. Nirenberg
worked on the small RNA molecules, tRNAs, which translate the genetic code into amino acid sequences of proteins.
Matthias Staehelin
won the 1961 Nobel Prize in Chemistry for his work on CO2 assimilation by plants.
Melvin Calvin
for their proposed structure of DNA, they shared in the 1962 Nobel Prize in Physiology and Medicine.
Francis Crick & James Watson
a physicist attracted to the problem genetic code, founded an informal group of like-minded scientists called the RNA Tie Club.
George Gamow
Symposium on The Genetic Code
1966
proved co-linearity of the gene—that is, that successive groups of nucleotides encoded successive amino acids in the protein product.
Charles Yanofsky
Symposium on Structure and Function of Proteins at the Three-Dimensional Level
1971
received the 1962 Nobel Prize for Chemistry; using X-ray crystallography, and after 25 years of effort, they were the first to solve the atomic structures of proteins—hemoglobin and myoglobin, respectively.
Max Perutz & John Kendrew
Symposium on The Synapse
1975
contributed to the discoveries of mRNA and the nature of the genetic code; his share of a Nobel Prize, in 2002, however, was for establishing the worm, Caenorhabditis elegans, as a model system for the study of developmental biology.
Sydney Brenner
Using phage genetics, defined the smallest unit of mutation, which turned out later to be a single nucleotide. *This same work also provided an experimental definition of the gene—which he called a cistron—using functional complementation tests. Later, his studies focused on behavior, using the fruit fly as a model.
Seymour Benzer
Mendel’s Law of Inheritance
Mendel and the pea plants
Mendel’s model 3:1 ratio
genetic composition or allele combination
genotype
- Greek root as phenomenon, meaning appearance.
- Physical structure of an individual.
- Observable traits
Phenotype
version of DNA sequence
Allele
organism has two copies of the same allele
- refers to a gene pair in which both the maternal and paternal genes are identical (e.g., RR or rr).
Homozygous
– organism has two different copies
- those gene pairs in which paternal and maternal genes are different (e.g., Rr)
Heterozygous
Mendel’s Discoveries
The Principle of Independent Segregation
Principle of Independent Assortment
Mendel’s law of ________ states that only one of the two gene copies present in an organism is distributed to each gamete (egg or sperm cell) that it makes, and the allocation of the gene copies is random.
segregation
can be used to predict genotypes(allele combinations) and phenotypes(observable traits) of offspring from genetic crosses.
Punnett Square
can be used to determine whether an organism with a dominant phenotype is homozygous or heterozygous
Test Cross
Mendel’slaw of ________states that the alleles of two (or more) different genes get sorted into gametes independently of one another.
independent assortment
