Dna/rna And Dna Replication
Compiled By Simon Mwangi
Edition: 2024/25
, Science | Biochemistry I of VI pages
1. Francis Crick, a graduate student, and an American postdoctoral fellow James Watson joined forces in late
at the Cavendish Laboratory at the University of Cambridge and began working together on the structure of
Observations of Erwin Chargaff on base composition of DNA
X-ray diffraction studies of Rosalind Franklin (and Maurice Wilkins)
2. Watsons and Cricks model of DNA was based on X-ray of Rosalind Franklin (at Kings College)
diffraction data
3. Watsons and Cricks Model Provides and explanation for Chargaffs Rule
of A=T and G=C
4. In Prokaryotic organisms the DNA is organized in a linear or contiguous fashion and transcription of the
template for protein synthesis (translation)
5. In Prokaryotic organisms the RNA transcript can be translated into a protein during the transcription
nucleus
6. In Eukaryotic organisms the DNA is broken up into regions or blocks of sequence that will give rise to the
protein sequence (coding regions or exons)
7. These exons are separated by (2)
regions that do not code for protein (introns) and regions at the 5 and 3 ends that do not encode protein called
8. In Eukaryotic organisms one strand of the DNA is first copied in a fashion and then the introns are
linear
splicing
9. Subsequent modifications take place that give rise to the mature mRNA, which is transported out of the
temple for protein synthesis (translation)
10. In Eukaryotic organisms primary transcripts are often spliced in multiple combinations of exons known as
alternative splicing
11. alternative splicing gives rise to a family of possible proteins that can have slightly different (3)
functions, regulation and/or tissue specificity (i.e. different splice variants are found in different tissues)
12. Linear DNA must be Condensed in order to
fit into a Cell or Nucleus
13. in prokaryotes, DNA is condensed by a set of and proteins in
polyamines
back and forth loops
14. in eukaryotes, DNA is first condensed into
nucleosomes
15. each nucleosome involves (2)
Biochemistry 2024/25 Edition