FT LEC: Nucleic Acids Flashcards
an unbranched polymer in which the monomer units are nucleotides
NUCLEIC ACIDS
Provides information on how to make new cells
NUCLEIC ACIDS
Who discovered Nucleic Acids?
Friedrich Miescher in 1869
Initially found in cell nuclei and are acidic in nature
NUCLEIC ACIDS
TYPES OF NUCLEIC ACIDS
- Deoxyribonucleic acid (DNA)
- Ribonucleic Acid (RNA)
Passes from existing cells to new cells during cell division/mitosis
Deoxyribonucleic acid (DNA)
Found within the cell nucleus
Deoxyribonucleic acid (DNA)
Stores and transfers genetic information
Deoxyribonucleic acid (DNA)
Occurs in all parts of a cell
Ribonucleic Acid (RNA)
Primary function is the synthesis of proteins
Ribonucleic Acid (RNA)
Building Blocks of Nucleic Acids
NUCLEOTIDE
a three-subunit molecule in which a pentose sugar is bonded to both a phosphate group and a nitrogen-containing heterocyclic base
NUCLEOTIDE
For DNA
2-deoxyribose
Components of a nucleotide
o Pentose sugar
o Heterocyclic base
o Phosphate group (PO43-)
For RNA
Ribose
Three pyrimidine derivatives
Thymine (T)
Cytosine (C)
Uracil (U)
Two purine derivatives
Adenine (A)
Guanine (G)
is found only in RNA
o Uracil
is found only in DNA
o Thymine
Derived from phosphoric acid (H3PO4)
PHOSPATE
The alternating sugar-phosphate chain in a nucleic acid structure is often called the
nucleic acid backbone
the sequence in which nucleotides are linked together in a nucleic acid
PRIMARY NUCLEIC ACID STRUCTURE
For DNA molecules, the backbone consists of alternating ___________
phosphate and deoxyribose sugar units
For RNA molecules, the backbone consists of alternating ___________
phosphate and ribose sugar units
Contains 2-deoxyribose
DNA
Does not contain uracil
DNA
Resistant to base hydrolysis
DNA
Contains ribose
RNA
Does not contain thymine
RNA
Sensitive to base hydrolysis
RNA
Human DNA contains
o 30% adenine
o 30% thymine
o 20% guanine
o 20% cytosine
A–T and G–C pairing is termed __________
complementary
most favored bonding in A–T and G–C pairs
o Hydrogen bonding
G-C pairs are held together by
3 hydrogen bonds
The total, unique DNA content of an organism is called its _________
genome
A-T pairs are held together by
2 hydrogen bonds
Two polynucleotide strands are coiled around each other in a spiral
DNA SEQUENCE
carries the genetic information from DNA for the synthesis of proteins necessary for cellular function
RNA
carries the genetic information of the cell
DNA
produce enough copies for itself and the production of a daughter cell during mitosis
REPLICATION
RNA is formed by
Transcription
Important enzymes in DNA replication include
- DNA Helicase
- DNA Polymerase
- DNA Ligase
responsible for unwinding the DNA double helix
DNA Helicase
Important enzyme in transcription process is
RNA polymerase
RNA is formed by ________ in order to carry information from DNA for protein synthesis. This process protects the DNA from mutations
Transcription
The processing of information stored in DNA into biomolecules that dictate biochemical processes in the cell involve three steps
o Replication
o Transcription
o Translation
Changes in DNA structure will affect the structure of proteins produced during translation
MUTATIONS
Alterations in the structure of DNA are called
mutations
Mutations can arise from exposure to physical or chemical agents that cause changes in DNA structure called __________
mutagens
substitution of one nucleotide to another
POINT MUTATION
removal of one or more nucleotides
DELETION MUTATION
one or more nucleotides are added into the sequence
INSERTION MUTATION
change in the DNA structure that does not change the amino acid coded
SILENT MUTATION
