Protein Synthesis and Gene Expression

Hot Seat

What is the relationship between the contents of the nuclei of muscle and intestine cells?

A. The cells function in exactly the same ways even though their nuclei are different

B. Both cells have the same DNA and use all of the genetic information available

C. The genes in the nuclei are identical but the information that is used is different

D. Muscle cells have genetic information that is very different from that of intestine cells

The result of transcription is

• DNA• mRNA• tRNA• protein

The result of translation is

A. DNAB. mRNAC. tRNAD. protein

There are 4 nucleotides that make up RNA. Codons consist of three adjacent nucleotides. Mathematically, there are 64 different codons, but we find only 20

common amino acids encoded by DNA in living systems. This suggests that…

A. Several codons are nonsenseB. Several codons code for each amino acidC. Several amino acids have the same codonD. More amino acids must be involved

The actual genetic code in genes has been shown to be

A. Triplet sequences (Codons) of nucleotides in DNA

B. Chemical bonds in amino acidsC. Protein chains in the cell nucleusD. Enzymes acting on ribosomal RNA

The coded material that travels from a cell nucleus to a ribosome where a particular protein will be synthesized is called

A. Ribosomal RNAB. Transfer RNAC. Messenger RNAD. Codon DNA

How has genetic engineering recently been put to use?

A. Producing bacteria that prevent frost damage on plants

B. Locating the genes that cause cystic fibrosisC. Inserting human DNA into bacteria to

manufacture insulinD. All of these

The “Central Dogma” of genetics states the usual order of events in protein synthesis proceeds along which of the following

sequences?

A. RNA DNA ProteinB. DNA Ribsome RNAC. DNA Protein RNAD. DNA RNA Protein

Which of the following contains T instead of U?

A. DNAB. mRNAC. tRNA

The three basepair sequence found on an mRNA strand is called the

A. CodonB. AnticodonC. CodaD. Genome

DNA gel electrophoresis separates DNA fragments by

A. DensityB. Strength of chargeC. Number of adenine subunitsD. Size

A mutation which results in the changing of all the codons following the error is called a “_____” mutation

A. Frameshift (insertion or deletion) B. Point mutationC. SubstitutionD. Chromosomal mutation

Proteins are synthesized at the

A. NucleusB. RibosomesC. MitochondriaD. lysosomes

Transfer RNA has a/an ______ complementary to a mRNA codon

A. AnticodonB. IntronC. CodonD. Interferon

During translation, a ribosome moves along and “reads” a molecule of

A. tRNAB. rRNAC. mRNAD. DNA

Each group of _____ bases on DNA or mRNA codes for an amino acid

A. OneB. TwoC. ThreeD. Four

Put the following steps of protein synthesis in order

1. mRNA leaves the nucleus with the DNA code, and goes to the ribosomes

2. ribosomes make proteins3. mRNA and tRNA meet in the ribosomes4. DNA temporarily unzips5. mRNA nucleotides match up to DNA

4, 5, 1, 3, 2

Decode the protein for which this gene codes

• 5’ TAC GCG TAA TGA 3’• 3’ AUG CGC AUU ACU 5’• Met – Arg – Iso – Thr

Label #1-6

1. DNA2. mRNA3. ribosome4. tRNA5. anticodon6. protein

In transcription, the nucleotide sequence CAT in DNA would specify _______________ in mRNA.

A. TACB. GUAC. GTAD. GTU

The function of tRNA is to:

A. Be the location for protein synthesisB. Transport amino acids to the ribosomeC. Read amino acidsD. Carry DNA’s message

The function of mRNA is to

A. Transport amino acids to the ribosomeB. Transcribe DNAC. Read amino acidsD. Break down DNA

Identify the polypeptide that would be produced as a result of transcribing and translating the following DNA sequence.

DNA: ...3' A C C A A G T C T 5'...

A. arg - phe – trpB. arg - leu – glyC. thr - lys – serD. trp - phe – argE. gly - leu - arg

Which suspect is guilty?

• Suspect #2 because his/her DNA fingerprint is an exact match to the DNA fingerprint from the crime scene.

Gene expression occurs when the ____________.

A. protein is madeB. cell dividesC. ribosome engages both the mRNA and tRNAD. DNA is replicated

Which father is the biological parent?

• Because the child’s DNA fingerprint matches 50% of each parent.

Your skin cells have different characteristics than your muscle cells, because __________.

A. your skin cells have the genes needed to form skin whereas your muscle cells have the genes needed to form muscles

B. your skin cells activate only those genes needed to make skin whereas your muscle cells activate only those genes needed to make muscle

C. your skin cells have different DNA codes than your muscle cells

D. your skin cells get mutated during development to change their characteristics from those of muscle cells

Write out the central dogma