Biochemistry
FIRST YEAR - FINAL TERM MRS. CECILIA VILLANUEVA 11/2021 - 01/2022
Digestion, Absorption, Metabolism
DNA FACTS Watson and Crick • Described the DNA
• DNA from a single human cell extends in a single
molecule from Franklin’s
• thread for almost 2 meters long!!!
X-ray. (1953)
• It contains information equal to some 600,000
printed pages of 500 words each!!! (a library of
about 1,000 books)
A HISTORY OF DNA
• The first isolation of what we now refer to as DNA
was accomplished by Johann Friedrich Miescher circa
1870.
• He reported finding a weakly acidic substance of
unknown function in the nuclei of human white X-ray diffraction • In 1953, based on X-ray
blood cells, and named this material "nuclein". A few Rosalind Franklin diffraction taken by Rosalind
years later, Miescher separated nuclein into protein and the information that the
and nucleic acid components. bases were paired, Watson
• In the 1920's nucleic acids were found to be major and Crick suggested what is
components of chromosomes, small gene-carrying now accepted as the first
bodies in the nuclei of complex cells. accurate model of DNA
• Elemental analysis of nucleic acids showed the structure in the journal.
presence of phosphorus, in addition to the usual C, Experimental evidence for
H, N & O. Unlike proteins, nucleic acids contained no Watson and Crick's model
sulfur. were published in a series of
• Complete hydrolysis of chromosomal nucleic acids five articles in the same issue
gave inorganic phosphate, 2-deoxyribose and four of Nature Of these
different heterocyclic bases. Wilkins & Franklin • Franklin’s paper was the first
• To reflect the unusual sugar component, (1952): X-ray publication of X-ray
chromosomal nucleic acids are called crystallography diffraction data that
deoxyribonucleic acids, abbreviated DNA. supported the Watson and
Analogous nucleic acids in which the sugar Crick model, this issue also
component is ribose are termed ribonucleic acids, contained an article on DNA
abbreviated RNA. The acidic character of the nucleic structure by Maurice Wilkins
acids was attributed to the phosphoric acid moiety. and his colleagues.
• In 1962, after Franklin's
death, Watson, Crick, and
Wilkins jointly received the
Discovery of the DNA double helix
Nobel prize. However,
Frederick Griffith • Discovers that a factor in
speculation continues on who
diseased bacteria can
should have received credit
transform harmless
for the discovery, as it was
bacteria into deadly
based on Franklin's data.
bacteria (1928)
DNA • Structure discovered by
Rosalind Franklin • X-ray photo of DNA.
Watson & Crick in 1953
(1952)
• Sides made of pentose (5-
sided) sugars attached to
phosphate groups by
phosphodiester bonds
• Pentose sugar called
, Biochemistry
FIRST YEAR - FINAL TERM MRS. CECILIA VILLANUEVA 11/2021 - 01/2022
Digestion, Absorption, Metabolism
The Double Helix
(1953)
THE NUCLEIC ACIDS
th
• The 4 type of macromolecules Nucleotides
• The chemical link between generations
• The source of genetic information in chromosomes
Genetic material of cells
• GENES – units of genetic material that CODES FOR A
SPECIFIC TRAIT
• Called NUCLEIC ACIDS
• DNA is made up of repeating molecules called
NUCLEOTIDES
• Dictates amino-acid sequence in proteins
• Gives information to chromosomes, which is then
passed from parent to offspring
Nucleotides
1. Phosphate Group
NUCLEIC ACID STRUCTURE
• Nucleic acids are polynucleotides
• Their building blocks are nucleotides
Components of Nucleic Acids
2. SUGAR--Ribose is a pentose
NUCLEOTIDE STRUCTURE
FIRST YEAR - FINAL TERM MRS. CECILIA VILLANUEVA 11/2021 - 01/2022
Digestion, Absorption, Metabolism
DNA FACTS Watson and Crick • Described the DNA
• DNA from a single human cell extends in a single
molecule from Franklin’s
• thread for almost 2 meters long!!!
X-ray. (1953)
• It contains information equal to some 600,000
printed pages of 500 words each!!! (a library of
about 1,000 books)
A HISTORY OF DNA
• The first isolation of what we now refer to as DNA
was accomplished by Johann Friedrich Miescher circa
1870.
• He reported finding a weakly acidic substance of
unknown function in the nuclei of human white X-ray diffraction • In 1953, based on X-ray
blood cells, and named this material "nuclein". A few Rosalind Franklin diffraction taken by Rosalind
years later, Miescher separated nuclein into protein and the information that the
and nucleic acid components. bases were paired, Watson
• In the 1920's nucleic acids were found to be major and Crick suggested what is
components of chromosomes, small gene-carrying now accepted as the first
bodies in the nuclei of complex cells. accurate model of DNA
• Elemental analysis of nucleic acids showed the structure in the journal.
presence of phosphorus, in addition to the usual C, Experimental evidence for
H, N & O. Unlike proteins, nucleic acids contained no Watson and Crick's model
sulfur. were published in a series of
• Complete hydrolysis of chromosomal nucleic acids five articles in the same issue
gave inorganic phosphate, 2-deoxyribose and four of Nature Of these
different heterocyclic bases. Wilkins & Franklin • Franklin’s paper was the first
• To reflect the unusual sugar component, (1952): X-ray publication of X-ray
chromosomal nucleic acids are called crystallography diffraction data that
deoxyribonucleic acids, abbreviated DNA. supported the Watson and
Analogous nucleic acids in which the sugar Crick model, this issue also
component is ribose are termed ribonucleic acids, contained an article on DNA
abbreviated RNA. The acidic character of the nucleic structure by Maurice Wilkins
acids was attributed to the phosphoric acid moiety. and his colleagues.
• In 1962, after Franklin's
death, Watson, Crick, and
Wilkins jointly received the
Discovery of the DNA double helix
Nobel prize. However,
Frederick Griffith • Discovers that a factor in
speculation continues on who
diseased bacteria can
should have received credit
transform harmless
for the discovery, as it was
bacteria into deadly
based on Franklin's data.
bacteria (1928)
DNA • Structure discovered by
Rosalind Franklin • X-ray photo of DNA.
Watson & Crick in 1953
(1952)
• Sides made of pentose (5-
sided) sugars attached to
phosphate groups by
phosphodiester bonds
• Pentose sugar called
, Biochemistry
FIRST YEAR - FINAL TERM MRS. CECILIA VILLANUEVA 11/2021 - 01/2022
Digestion, Absorption, Metabolism
The Double Helix
(1953)
THE NUCLEIC ACIDS
th
• The 4 type of macromolecules Nucleotides
• The chemical link between generations
• The source of genetic information in chromosomes
Genetic material of cells
• GENES – units of genetic material that CODES FOR A
SPECIFIC TRAIT
• Called NUCLEIC ACIDS
• DNA is made up of repeating molecules called
NUCLEOTIDES
• Dictates amino-acid sequence in proteins
• Gives information to chromosomes, which is then
passed from parent to offspring
Nucleotides
1. Phosphate Group
NUCLEIC ACID STRUCTURE
• Nucleic acids are polynucleotides
• Their building blocks are nucleotides
Components of Nucleic Acids
2. SUGAR--Ribose is a pentose
NUCLEOTIDE STRUCTURE
