D2.2 Gene expression [HL only]

Insulin is produced in β cells of the pancreas and not in other cells of the human body. Explain how differentiation of cells and regulation of gene expression allow proteins such as insulin to be produced in only certain types of body cell.

Insulin is produced in β cells of the pancreas and not in other cells of the human body. Explain how differentiation of cells and regulation of gene expression allow proteins such as insulin to be produced in only certain types of body cell.

Insulin is produced in β cells of the pancreas and not in other cells of the human body. Explain how differentiation of cells and regulation of gene expression allow proteins such as insulin to be produced in only certain types of body cell.

The micrograph of a section through a plant stem shows at least ten different types of cells.

[Source: Joan Carles Juarez / Shutterstock.com.]

What explains the differences between these cells?

A. Only one gene is expressed in each cell type.

B. Different genes are expressed in each cell type.

C. Only useful genes remain in the DNA of each cell type.

D. Changes in the DNA sequence take place when these cells develop.

Which statement correctly describes genome and proteome?

A. Only the genome but not the proteome can be analysed using gel electrophoresis.

B. The genome and the proteome are the same in all tissues in an organism.

C. In cells of different tissues, the genome is the same while the proteome varies.

D. Only mutations in the proteome but not in the genome cause any variability.

The micrograph of a section through a plant stem shows at least ten different types of cells.

[Source: Joan Carles Juarez / Shutterstock.com.]

What explains the differences between these cells?

A. Only one gene is expressed in each cell type.

B. Different genes are expressed in each cell type.

C. Only useful genes remain in the DNA of each cell type.

D. Changes in the DNA sequence take place when these cells develop.

Which statement correctly describes genome and proteome?

A. Only the genome but not the proteome can be analysed using gel electrophoresis.

B. The genome and the proteome are the same in all tissues in an organism.

C. In cells of different tissues, the genome is the same while the proteome varies.

D. Only mutations in the proteome but not in the genome cause any variability.

Outline how nucleosomes affect the transcription of DNA.

The graph shows the effect of methylation on the expression of MT1E, a gene involved in the control of prostate cancer development. Patients with a reduced expression of this gene are more likely to develop prostate cancer.

_{[Source: © 2017 Demidenko et al. 2017. Decreased expression of MT1E is a potential biomarker of
prostate cancer progression. Oncotarget, 8, pp. 61709–61718. Distributed under the terms of the Creative Commons Attribution License 3.0 (CC BY 3.0). Image redrawn and reannotated.]}

What are effects of MT1E methylation?

A.  It reduces transcription of MT1E, increasing the risk of prostate cancer.

B.  It increases translation of MT1E, reducing the risk of prostate cancer.

C.  It reduces replication of MT1E, reducing the risk of prostate cancer.

D.  It increases the chances of mutation in proto-oncogenes, increasing the risk of prostate cancer.

DNA methylation profiles in zebrafish (Danio rerio) gametes were determined. The methylated areas were divided into three groups according to the amount of methylation: high, medium and low methylation.

^{[Source: Potok, M.E., Nix, D.A., Parnell, T.J. and Cairns, B.R., 2013.
Reprogramming the Maternal Zebrafish Genome afterFertilization to
Match the Paternal Methylation Pattern.
Cell, [e-journal] 153(4), pp. 759–772. http://dx.doi.org/10.1016/j.
cell.2013.04.030.]}

Methylation of DNA in sperm and egg is removed immediately after fertilization. What is the reason for this?

A.  Methylation allows RNA polymerase to join the promoter.

B.  It is needed to form homologous pairs of chromosomes.

C.  It allows expression of genes linked to early development.

D.  Transcription of promoters only occurs in methylated genes.

The graph shows the effect of methylation on the expression of MT1E, a gene involved in the control of prostate cancer development. Patients with a reduced expression of this gene are more likely to develop prostate cancer.

_{[Source: © 2017 Demidenko et al. 2017. Decreased expression of MT1E is a potential biomarker of
prostate cancer progression. Oncotarget, 8, pp. 61709–61718. Distributed under the terms of the Creative Commons Attribution License 3.0 (CC BY 3.0). Image redrawn and reannotated.]}

What are effects of MT1E methylation?

A.  It reduces transcription of MT1E, increasing the risk of prostate cancer.

B.  It increases translation of MT1E, reducing the risk of prostate cancer.

C.  It reduces replication of MT1E, reducing the risk of prostate cancer.

D.  It increases the chances of mutation in proto-oncogenes, increasing the risk of prostate cancer.

The graph shows the effect of methylation on the expression of MT1E, a gene involved in the control of prostate cancer development. Patients with a reduced expression of this gene are more likely to develop prostate cancer.

_{[Source: © 2017 Demidenko et al. 2017. Decreased expression of MT1E is a potential biomarker of
prostate cancer progression. Oncotarget, 8, pp. 61709–61718. Distributed under the terms of the Creative Commons Attribution License 3.0 (CC BY 3.0). Image redrawn and reannotated.]}

What are effects of MT1E methylation?

A.  It reduces transcription of MT1E, increasing the risk of prostate cancer.

B.  It increases translation of MT1E, reducing the risk of prostate cancer.

C.  It reduces replication of MT1E, reducing the risk of prostate cancer.

D.  It increases the chances of mutation in proto-oncogenes, increasing the risk of prostate cancer.

Outline how nucleosomes affect the transcription of DNA.

Outline how nucleosomes affect the transcription of DNA.

The graph shows the effect of methylation on the expression of MT1E, a gene involved in the control of prostate cancer development. Patients with a reduced expression of this gene are more likely to develop prostate cancer.

_{[Source: © 2017 Demidenko et al. 2017. Decreased expression of MT1E is a potential biomarker of
prostate cancer progression. Oncotarget, 8, pp. 61709–61718. Distributed under the terms of the Creative Commons Attribution License 3.0 (CC BY 3.0). Image redrawn and reannotated.]}

What are effects of MT1E methylation?

A.  It reduces transcription of MT1E, increasing the risk of prostate cancer.

B.  It increases translation of MT1E, reducing the risk of prostate cancer.

C.  It reduces replication of MT1E, reducing the risk of prostate cancer.

D.  It increases the chances of mutation in proto-oncogenes, increasing the risk of prostate cancer.

DNA methylation profiles in zebrafish (Danio rerio) gametes were determined. The methylated areas were divided into three groups according to the amount of methylation: high, medium and low methylation.

^{[Source: Potok, M.E., Nix, D.A., Parnell, T.J. and Cairns, B.R., 2013.
Reprogramming the Maternal Zebrafish Genome afterFertilization to
Match the Paternal Methylation Pattern.
Cell, [e-journal] 153(4), pp. 759–772. http://dx.doi.org/10.1016/j.
cell.2013.04.030.]}

Methylation of DNA in sperm and egg is removed immediately after fertilization. What is the reason for this?

A.  Methylation allows RNA polymerase to join the promoter.

B.  It is needed to form homologous pairs of chromosomes.

C.  It allows expression of genes linked to early development.

D.  Transcription of promoters only occurs in methylated genes.

State one reason that identical twins may show different methylation patterns as they grow older.

The graph shows the effect of methylation on the expression of MT1E, a gene involved in the control of prostate cancer development. Patients with a reduced expression of this gene are more likely to develop prostate cancer.

_{[Source: © 2017 Demidenko et al. 2017. Decreased expression of MT1E is a potential biomarker of
prostate cancer progression. Oncotarget, 8, pp. 61709–61718. Distributed under the terms of the Creative Commons Attribution License 3.0 (CC BY 3.0). Image redrawn and reannotated.]}

What are effects of MT1E methylation?

A.  It reduces transcription of MT1E, increasing the risk of prostate cancer.

B.  It increases translation of MT1E, reducing the risk of prostate cancer.

C.  It reduces replication of MT1E, reducing the risk of prostate cancer.

D.  It increases the chances of mutation in proto-oncogenes, increasing the risk of prostate cancer.

DNA methylation profiles in zebrafish (Danio rerio) gametes were determined. The methylated areas were divided into three groups according to the amount of methylation: high, medium and low methylation.

^{[Source: Potok, M.E., Nix, D.A., Parnell, T.J. and Cairns, B.R., 2013.
Reprogramming the Maternal Zebrafish Genome afterFertilization to
Match the Paternal Methylation Pattern.
Cell, [e-journal] 153(4), pp. 759–772. http://dx.doi.org/10.1016/j.
cell.2013.04.030.]}

Methylation of DNA in sperm and egg is removed immediately after fertilization. What is the reason for this?

A.  Methylation allows RNA polymerase to join the promoter.

B.  It is needed to form homologous pairs of chromosomes.

C.  It allows expression of genes linked to early development.

D.  Transcription of promoters only occurs in methylated genes.

The graph shows the effect of methylation on the expression of MT1E, a gene involved in the control of prostate cancer development. Patients with a reduced expression of this gene are more likely to develop prostate cancer.

_{[Source: © 2017 Demidenko et al. 2017. Decreased expression of MT1E is a potential biomarker of
prostate cancer progression. Oncotarget, 8, pp. 61709–61718. Distributed under the terms of the Creative Commons Attribution License 3.0 (CC BY 3.0). Image redrawn and reannotated.]}

What are effects of MT1E methylation?

A.  It reduces transcription of MT1E, increasing the risk of prostate cancer.

B.  It increases translation of MT1E, reducing the risk of prostate cancer.

C.  It reduces replication of MT1E, reducing the risk of prostate cancer.

D.  It increases the chances of mutation in proto-oncogenes, increasing the risk of prostate cancer.

The graph shows the effect of methylation on the expression of MT1E, a gene involved in the control of prostate cancer development. Patients with a reduced expression of this gene are more likely to develop prostate cancer.

_{[Source: © 2017 Demidenko et al. 2017. Decreased expression of MT1E is a potential biomarker of
prostate cancer progression. Oncotarget, 8, pp. 61709–61718. Distributed under the terms of the Creative Commons Attribution License 3.0 (CC BY 3.0). Image redrawn and reannotated.]}

What are effects of MT1E methylation?

A.  It reduces transcription of MT1E, increasing the risk of prostate cancer.

B.  It increases translation of MT1E, reducing the risk of prostate cancer.

C.  It reduces replication of MT1E, reducing the risk of prostate cancer.

D.  It increases the chances of mutation in proto-oncogenes, increasing the risk of prostate cancer.

State one reason that identical twins may show different methylation patterns as they grow older.

State one reason that identical twins may show different methylation patterns as they grow older.

The graph shows the effect of methylation on the expression of MT1E, a gene involved in the control of prostate cancer development. Patients with a reduced expression of this gene are more likely to develop prostate cancer.

_{[Source: © 2017 Demidenko et al. 2017. Decreased expression of MT1E is a potential biomarker of
prostate cancer progression. Oncotarget, 8, pp. 61709–61718. Distributed under the terms of the Creative Commons Attribution License 3.0 (CC BY 3.0). Image redrawn and reannotated.]}

What are effects of MT1E methylation?

A.  It reduces transcription of MT1E, increasing the risk of prostate cancer.

B.  It increases translation of MT1E, reducing the risk of prostate cancer.

C.  It reduces replication of MT1E, reducing the risk of prostate cancer.

D.  It increases the chances of mutation in proto-oncogenes, increasing the risk of prostate cancer.

DNA methylation profiles in zebrafish (Danio rerio) gametes were determined. The methylated areas were divided into three groups according to the amount of methylation: high, medium and low methylation.

^{[Source: Potok, M.E., Nix, D.A., Parnell, T.J. and Cairns, B.R., 2013.
Reprogramming the Maternal Zebrafish Genome afterFertilization to
Match the Paternal Methylation Pattern.
Cell, [e-journal] 153(4), pp. 759–772. http://dx.doi.org/10.1016/j.
cell.2013.04.030.]}

Methylation of DNA in sperm and egg is removed immediately after fertilization. What is the reason for this?

A.  Methylation allows RNA polymerase to join the promoter.

B.  It is needed to form homologous pairs of chromosomes.

C.  It allows expression of genes linked to early development.

D.  Transcription of promoters only occurs in methylated genes.

What is the difference between the DNA of adult identical (monozygotic) twins?

A. Order of genes

B. Sequence of nucleotides

C. Methylation pattern

D. Ratio of complementary base pairs

What is the difference between the DNA of adult identical (monozygotic) twins?

A. Order of genes

B. Sequence of nucleotides

C. Methylation pattern

D. Ratio of complementary base pairs