Gene expression is the process of using information from a gene to create a functional gene product. This product can then produce end products, such as proteins or non-coding RNA, which can affect a phenotype. Gene expression involves transcribing genes into mRNAs, and then translating the mRNAs into proteins. The central dogma of molecular biology describes the directional flow of information during the expression of a protein-coding gene. This flow goes from DNA to RNA to protein.  Gene expression is important because a specific protein can only be produced when its gene is turned on. It... Show more

Gene expression is the process of using information from a gene to create a functional gene product. This product can then produce end products, such as proteins or non-coding RNA, which can affect a phenotype.

Gene expression involves transcribing genes into mRNAs, and then translating the mRNAs into proteins. The central dogma of molecular biology describes the directional flow of information during the expression of a protein-coding gene. This flow goes from DNA to RNA to protein. 
Gene expression is important because a specific protein can only be produced when its gene is turned on. It is also vital for maintaining normal cellular structure and function, and is the basis for developmental changes. 

Only a fraction of the genes in a cell are expressed at any one time.

Topics include: Transcription, Ribosomal RNA & tRNA, Messenger RNA, Regulation & Silencing, Genetic Code Properties, Genetic Code Decoding, & Translation.

Related: Cell Biology Practice Test: Nature of Genome 

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Cell Biology Practice Test: Gene Expression

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25 Questions

1. Which proteolytic enzyme was used in the experiments aimed at elucidating the mutation that causes sickle cell anemia?

pepsinpapaintrypsinrennin

2. 5S rRNA is present only in eukaryotes.

FalseTrueMaybeDon't Know

3. The length of tRNA molecules is ________________ nucleotides.

83-9320-3073-9350-70

4. Transcription is the synthesis of ______________________

ProteinPolypeptideRNADNA

5. Messenger RNAs are found in the ________________

nucleuslysosomecytoplasmnucleolus

6. In the below figure of a transfer RNA, which is the site of attachment for an amino acid?

adbc

7. When was the link between enzymes and inherited disease first elucidated?

1908180820081708

8. How many types of distinct ribosomal RNAs are present in eukaryotic ribosomes?

2431

9. How many post-translational modifications occur in the pre-rRNA (primary transcript)?

4312

10. Which of the following is a stop codon in mitochondrial mRNA?

AUGAGGUUUUGA

11. When was the first base sequence of a transfer RNA reported?

1945195519651935

12. In bacteria, binding of _________ factor to the RNA polymerase increases its affinity for promoter sites in the DNA.

betarhosigmaalpha

13. Which organism was used for experiments that led to “one gene – one enzyme” hypothesis?

NeurosporaMus musculusDrosophilaNematode

14. In patients of sickle cell anemia, the hemoglobin contains a substitution for ____________________

ascorbic acidquinonecarboxylic acidglutamic acid

15. The genetic code is degenerate.

MaybeFalseDon't KnowTrue

16. In a mammalian cell, which is the most abundant type of RNA?

rRNAtRNAmRNAsiRNA

17. First artificially synthesized gene sequence was _________________

poly(U)poly(C)poly(A)poly(G)

18. Which technique was used to find the relationship between 15S and 10S globin RNAs?

Polymerase chain reactionS-loop formationPulsed-field gel electrophoresisR-loop formation

19. Eukaryotic mRNAs have special modifications, not present in prokaryotic mRNAs.

FalseTrueDon't KnowMaybe

20. Which of the following is a pre-rRNA?

5.8S5S18S45S

21. Which among the following have the largest number of tRNA genes?

humansbacteriayeastfruit flies

22. Aggregated clusters of rDNA in a cell are called _______________

chromosomenucleoliribosomechromatin

23. RNA interference is evolved as a genetic immune system.

MaybeTrueFalseDon't Know

24. RNA interference is not observed in vertebrates.

MaybeDon't KnowTrueFalse

25. The processing of pre-rRNA is done using __________

snoRNAmRNAsiRNAnucleolus