MBG TEST 1 EXAM QUESTIONS WITH
VERIFIED ANSWERS
A gene has to be __________ before it can be ___________ to the next generation
replicated; transmitted
A gene has to be __________ to produce a phenotype
Expressed
What makes DNA?
bringing together subunits called deoxyribonucleotides (dNTPs)
where does phosphate attach to deoxyribose in the dNTP structure?
the 5' carbon of deoxyribose
What does the phosphate attached to the 5' carbon interact with?
the 3' carbon of the growing DNA chain
Structure of Deoxyribose
5 carbon ring
H at 2C rather than OH (deoxy)
Visual of the growing chain. What type of polarity does the growing chain have?
5' to 3' polarity
What makes up the DNA double helix?
Two strands running anti-parallel
What makes DNA an acid?
The phosphate backbone has a negative charge which makes it an acid
What is the importance of the negative charge of DNA?
interaction with water
interaction with proteins
chromosome structure
Gel electrophoresis
,How many nitrogenous bases are there for DNA? What are they?
4:
2 Pyrimidines: Thymine and Cytosine
2 Purines: Adenine and Guanine
Which bases are double rings?
Purines: Adenine and Guanine
Which bases are single rings?
Pyrimidines: Thymine and Cytosine
What are the 4 bases of dNTP?
dTTP
dCTP
dATP
dGTP
What is the base pairing in the double helix of DNA?
Adenine and Thymine
Guanine and Cytosine
What type of bond is used in base pairing?
Hydrogen bonds
Which bond is stronger? G-C or A-T?
G-C bond is stronger than A-T because G-C has 3 H bonds and takes more energy to break than
A-T which only has 2 H bonds
How is the DNA code written?
In a single letter code from 5' to 3'
What is the single most important principle in molecular biology, both in nature and in the
lab?
The complimentary base pair
How can DNA be measured or sought out from a complex mixture of DNA molecules?
By making an oligo in a lab and use it as a probe to bind to the target DNA
What is an oligo?
A short stretch of DNA made in a lab to be used to target a DNA strand
, What is the Central Dogma?
The direction of information flow
(DNA --> RNA --> proteins)
What is the first step of Gene expression?
transcription
What is transcription?
Transcription has the main goal of converting a sequence of DNA into a single stranded mRNA
Differences between DNA and RNA
DNA has deoyribose, thymine, only has 1 -OH, and is double-stranded.
RNA has ribose, uracil, has 2 -OH, and is single-stranded
In the environment, ______ is short lived and unstable, whereas ______ is very stable and
intact for long periods of time.
RNA; DNA
Coding strand
The strand of DNA used for transcription of a gene
What step of gene expression follows after transcription?
Translation
mRNA role in gene expression
The RNA transcript that will be translated into a polypeptide
What are the building blocks of polypeptides?
amino acids
What bond is used for amino acids? Where is the bond?
Peptide bond
Between the C-terminus of one amino acid and the N-terminus of the next
What is a codon?
a sequence of three nucleotides that together form a unit of genetic code in a DNA or RNA
molecule that code for one amino acid.
AGG codes for Arginine (Arg)
VERIFIED ANSWERS
A gene has to be __________ before it can be ___________ to the next generation
replicated; transmitted
A gene has to be __________ to produce a phenotype
Expressed
What makes DNA?
bringing together subunits called deoxyribonucleotides (dNTPs)
where does phosphate attach to deoxyribose in the dNTP structure?
the 5' carbon of deoxyribose
What does the phosphate attached to the 5' carbon interact with?
the 3' carbon of the growing DNA chain
Structure of Deoxyribose
5 carbon ring
H at 2C rather than OH (deoxy)
Visual of the growing chain. What type of polarity does the growing chain have?
5' to 3' polarity
What makes up the DNA double helix?
Two strands running anti-parallel
What makes DNA an acid?
The phosphate backbone has a negative charge which makes it an acid
What is the importance of the negative charge of DNA?
interaction with water
interaction with proteins
chromosome structure
Gel electrophoresis
,How many nitrogenous bases are there for DNA? What are they?
4:
2 Pyrimidines: Thymine and Cytosine
2 Purines: Adenine and Guanine
Which bases are double rings?
Purines: Adenine and Guanine
Which bases are single rings?
Pyrimidines: Thymine and Cytosine
What are the 4 bases of dNTP?
dTTP
dCTP
dATP
dGTP
What is the base pairing in the double helix of DNA?
Adenine and Thymine
Guanine and Cytosine
What type of bond is used in base pairing?
Hydrogen bonds
Which bond is stronger? G-C or A-T?
G-C bond is stronger than A-T because G-C has 3 H bonds and takes more energy to break than
A-T which only has 2 H bonds
How is the DNA code written?
In a single letter code from 5' to 3'
What is the single most important principle in molecular biology, both in nature and in the
lab?
The complimentary base pair
How can DNA be measured or sought out from a complex mixture of DNA molecules?
By making an oligo in a lab and use it as a probe to bind to the target DNA
What is an oligo?
A short stretch of DNA made in a lab to be used to target a DNA strand
, What is the Central Dogma?
The direction of information flow
(DNA --> RNA --> proteins)
What is the first step of Gene expression?
transcription
What is transcription?
Transcription has the main goal of converting a sequence of DNA into a single stranded mRNA
Differences between DNA and RNA
DNA has deoyribose, thymine, only has 1 -OH, and is double-stranded.
RNA has ribose, uracil, has 2 -OH, and is single-stranded
In the environment, ______ is short lived and unstable, whereas ______ is very stable and
intact for long periods of time.
RNA; DNA
Coding strand
The strand of DNA used for transcription of a gene
What step of gene expression follows after transcription?
Translation
mRNA role in gene expression
The RNA transcript that will be translated into a polypeptide
What are the building blocks of polypeptides?
amino acids
What bond is used for amino acids? Where is the bond?
Peptide bond
Between the C-terminus of one amino acid and the N-terminus of the next
What is a codon?
a sequence of three nucleotides that together form a unit of genetic code in a DNA or RNA
molecule that code for one amino acid.
AGG codes for Arginine (Arg)
