DNA is heritable material Flashcards
In 1928, he was credited with recognizing TRANSFORMATION in bacteria.
Frederick Griffith
In what year did Griffith discover the pneumoniae shit?
1928
Disease-causing (pathogenic) baterium causing pneumonia
Streptococcus pneumoniae
The _____ is a virulence factor.
Capsule
What are the 2 strains of streptococcus?
- Pathogenic (capsule; virulent) S-strain
2. Non-pathogenic (capsule-free; non-virulent) R-strain
What is pathogenic strain?
S-strain
What is non-pathogenic strain?
R-strain
Griffith’s conclusion?
Transformation adds new pieces of genes to live bacterial cells
The transfer of information is called ___.
Transformation
Transforming bacteria nowadays is to insert foreign DNA into bacteria to allow microbe to produce molecule like ______ & ______.
Human growth hormone
Human insulin
Two macromolecules became candidates for genetic material when it was shoed that genes were located on chromosomes. What are they?
DNA (4 different monomers)
Protein (20 different monomers)
When did Avery, MacLeod, & McCarty repeat Griffith’ experiment?
1944
In 1944, Griffith’s experiemtn was repeated by whom?
Avery, MacLeod, & McCarty
What did Avery, MacLeod, & McCarty discover?
degradation of protein did not destroy its ability to transform Rstrain cells but degraded DNA destruyed all transforming ability
What is Avery, MacLeod, & McCarty’s conclusion?
The molecule that carries the heritable information is DNA.
In what year did Hershey and Chase did their discovery?
1952
What did Hershey and Chase discover?
performed experiments showing that DNA is the genetic material of a phage known as T2 with blender experiment
Viruses that infect bacteria.
Bacteriophage
What composes bacteriophage?
DNA packed inside head and protein making up the outer coat
How to distinguish DNA from protein?
Protein: some amino acids contain sulfur,but NEVER phosphorous
DNA: have phosphorous , but NEVER sulfur
Only the bacteriophage ____ entered the bacteria
DNA
What is Hershey and Chase’s conclusion?
DNA is the genetic material since radioactive DNA ended up in viral offsrping
