Download 1) codon 2) gene 3) polypeptide 4) nucleotide 1. A sequence of

1. A sequence of three nitrogenous bases in a messenger-RNA
molecule is known as a
1) codon
3) polypeptide
Base your answers to questions 5 and 6 on the chart below and
on your knowledge of biology.
2) gene
4) nucleotide
2. The inability of an organism to produce certain proteins can occur
when an organism is lacking an enzyme needed to combine
1) oxygen molecules
3) amino acids
2) simple sugars
4) biological catalysts
3. Which statement indicates one difference between the gene that
codes for insulin and the gene that codes for testosterone in
humans?
1) The gene for insulin is replicated in vacuoles, while the gene
for testosterone is replicated in mitochondria.
2) The gene for insulin has a different sequence of
molecular bases than the gene for testosterone.
3) The gene for insulin is turned on in liver cells, but the gene
for testosterone is not.
4) The gene for insulin is a sequence of five different
molecular bases while the gene for testosterone is a
sequence of only four different molecular bases.
4. Four stages in the production of protein molecules in a cell are
listed below.
A – Transfer RNA molecules bring amino acids
to the ribosome
B – DNA molecules serve as templates for
messenger RNA molecules.
C – Messenger RNA molecules move to
ribosomes.
D – Polypeptides are formed on ribosomes.
Which sequence best represents the correct order of these stages?
1) A
3) C
B
B
C
A
D
D
2) B
4) D
C
B
A
A
D
C
5. Which amino acid will be carried to a ribosome by a transfer
RNA molecule containing the triplet code A–A–A?
1) valine
3) leucine
2) lysine
4) phenylalanine
6. Which base sequence of a DNA molecule produces a codon on an
mRNA molecule that will allow the amino acid arginine to be
incorporated into a protein?
1) C – G – A
3) C – G – U
2) G – C – T
4) G – C – U
7. Which is a major difference between messenger RNA molecules
and transfer RNA molecules?
1) Messenger RNA molecules contain ribose, and transfer
RNA molecules contain deoxyribose.
2) Messenger RNA molecules function in carrying coded
information to the ribosomes, and transfer RNA
molecules function in carrying amino acids to the
ribosomes.
3) Messenger RNA molecules contain thymine, and transfer
RNA molecules contain uracil.
4) Messenger RNA molecules function when they are
double-stranded, and transfer RNA molecules function
when they are single-stranded.
8. DNA controls cellular activities most directly by coding for the
synthesis of
1) inorganic compounds
3) carbohydrates
2) enzymes
4) fatty acids
9. What is the relationship between an organism's DNA and protein
specificity?
1) DNA becomes a specific part of the protein structure.
2) DNA determines the ribosomal RNA sequence that becomes
part of the protein structure.
3) DNA determines which RNA molecules are incorporated
into protein molecules.
4) DNA determines the amino acid sequence of each
protein.
10. Base your answer to the following question on the diagram
below, which provides information related to heredity.
Which molecules are represented by box B?
1) bases
3) amino acids
2) proteins
4) simple sugars
11. Base your answer to the following question on the table below, which represents the DNA codes for several amino acids.
A certain DNA strand has the base sequence: TACACACAAACGGGG. In the space provided below, write the sequence
of amino acids synthesized from this code if it is read from left to right.
Answer Key
protein synth qui rvew
1.
1
2.
3
3.
2
4.
2
5.
4
6.
2
7.
2
8.
2
9.
4
10.
2
11.
methionine – cysteine
– valine – cysteine –
proline