2.6 & 2.7 Review Quizizz

This is a sequence of nucleotides from a section of mRNA.

AUGAAACGCACGCAG

From which DNA sequence has it been transcribed?

• ATGAAACGCACGCAG

• UACUUUGCGUGCGAC

• TACUUUGCGTGCGTC

• TACTTTGCGTGCGTC

How is the information in the genetic code used?

• To predict the genotype of gametes

• To distinguish prokaryotic genomes from eukaryotic genomes

• To deduce phenotypes in pedigree charts

• To translate mRNA into polypeptides

The gene that codes for a particular polypeptide includes the base sequence shown.

GAGTACCCT

What is the base sequence of the mRNA molecule which is complementary to this sequence?

• GAGTACCCT

• CTCATGGGA

• GUGTUCCCT

• CUCAUGGGA

Where are amino acids joined together to make polypeptides?

• Nucleus

• Nucleolus

• Golgi apparatus

• Ribosomes

What do DNA replication, transcription and translation have in common?

• Take place in cell nucleus

• Require free nucleotides

• Catalysed by polymerase

• Complementary base pairing

Some yeast genes can be replaced by human genes that then continue to produce the same human proteins in the yeast cells. Which statement helps to explain this evidence?

• The DNA of yeast and humans is identical.

• Yeast and humans have the same number of chromosomes.

• The genetic code is universal.

• Yeast and humans are both eukaryotes.

Meselson and Stahl investigated DNA replication by first feeding bacteria with bases containing 15N (heavy), and then with bases containing 14N (light). The results are shown in the photographs.

From this information, what would be the composition of the DNA in generation 3?

• There will be a single 14N band.

• There will be a single 15N band and a single 14N band.

• There will be a darker 14N band and a lighter hybrid band.

• There will be a single 15N band, a single hybrid band and a single 14N band.

The table shows the genetic code.

Which mRNA could code for the sequence Met-Ser-Leu-Arg-Phe?

• AUG UCA UCG UGG UUU

• AUG UCC ACC AGA UUC

• AUG UCU CCC AGA UUU

• AUG UCG CUG AGG UUC

Meselson and Stahl conducted experiments using the isotopes 14N and 15N which showed that DNA replication is semi-conservative. What would they have observed about the distribution of isotopes in the DNA after one round of replication if DNA replication was conservative rather than semi-conservative?

• Only 14N DNA

• Only 15N DNA

• All DNA half 14N and half 15N

• Half the DNA with only 14N and half with only 15N

Which are necessary to make DNA replication semi-conservative?

I. Separation of the strands by RNA polymerase

II. Complementary base pairing

III. Use of a pre-existing strand as a template

• I and II only

• I and III only

• II and III only

• I, II and III