Genes

Question 1

What is DNA methylation?

Answer 1

The adding of a methyl group or CH3 to a nucleotide.

Question 2

What is epigenetics in simple terms?

Answer 2

Modification of expression of genes.

Question 3

What are exonucleases?

Answer 3

The groups that remove nucleotides one by one from an mRNA.

Question 4

What do Deadenylation complexes do?

Answer 4

They remove the poly - A tail from the mRNA.

Question 5

What are promoter regions?

Answer 5

Base sequence where RNA polymerase binds to begin transcription

Question 6

What are transcription factors?

Answer 6

DNA binding protein that controls transcription by binding to an enhancer or a silencer.

Question 7

What are enhancers?

Answer 7

base sequence that promotes transcription when a transcription factor binds there.

Question 8

What is a silencer?

Answer 8

base sequence that blocks transcription when a transcription factor binds there.

Question 9

Which of the following is directly involved in controlling gene expression?

I. DNA replication
II. RNA splicing
III. mRNA degradation
IV. Histone modification

Answer 9

II, III and IV only

Question 10

What is the impact of epigenetic changes on gene expression?
A. To alter the DNA base sequence thus affecting genotype
B. To change the phenotype without altering the genotype
C. To prevent translation of proteins
D. To silence genes permanently

Answer 10

B

Question 11

In order from smallest to biggest, which is correct?
A. Proteome, transcriptome, genome
B. Genome, proteome, transcriptome
C. Genome, transcriptome, proteome
D. Transcriptome, genome, proteome

Answer 11

C

Question 12

Which statement is true regarding the lac operon?
A. It shows an example of allosteric inhibition of an enzyme
B. It regulates the expression of genes involved in lactose metabolism
C. It shows an example of hormone regulation of gene expression
D. It functions as a transcription factor for gene activation

Answer 12

B

Question 13

How do transcription factors regulate gene expression?
A. By interacting with DNA polymerase
B. By binding to activator sequences and increasing the rate of transcription
C. By mediating binding of RNA polymerase to the promoter
D. By binding to repressor sequences and decreasing the rate of transcription

Answer 13

C

Question 14

What happens if a mitochondria is not present in the daughter cell?

Answer 14

The cell is not able to produce replacement Mitochondria.

Question 15

What are the two examples of unequal division in cells?

Answer 15

1. Budding in yeast - form of sexual reproduction where a small daughter cell buds off a larger cell by cytokinesis.
2. Oogenesis - formation of eggs in females, involves unequal division of cells during meiosis to produce one large egg cell.

Question 16

What are cells produced without a nucleus called?

Answer 16

Anucleate

Question 17

How are sister chromatids held together?

Answer 17

By a center centromere

Question 18

When are sister chromatids separated?

Answer 18

During Anaphase of mitosis and Anaphase II of Meiosis.

Question 19

What are mutagens?

Answer 19

The agents that cause permanent heritable changes to the DNA of cells.
Examples include gamma rays, UV light, and x-rays.

Question 20

Which nitrogen base has the highest probability of mutation?

Answer 20

Cytosine

Question 21

What are somatic cells?

Answer 21

Cells that are not passed on and not used for reproduction.

Question 22

What do mutations to proto-oncogenes in somatic cells result in?

Answer 22

Uncontrolled cell division / cancer.

Question 23

What is gene knockout?

Answer 23

A technique where a targeted gene is inactivated or removed from an organism.

Question 24

What are the uses of CRISPR and cas-9?

Answer 24

1. Gene-therapy : used to replace of repair a gene that is responsible for genetic diseases.
2. Genetic Research : method to knock out genes, allowing researchers to better understand the action of specific genes.
3. Malaria prevention : can be used to modify the genomes of mosquitoes which could reduce the spread of Malaria.

Question 25

What are epigenetic tags?

Answer 25

chemical markers that attach to DNA or histone proteins and influence the transcription of genes.

Question 26

What is non-disjunction?

Answer 26

a failure of one or more pairs of homologous chromosomes or sister chromatids to separate fully during nuclear division. Can occur during Anaphase I or Anaphase II of Meiosis.

Question 27

What is down syndrome caused by?

Answer 27

Usually caused by non-disjunction where there are 3 copies of chromosome 21

Question 28

What are cyclins?

Answer 28

groups of four proteins which control the movement of a cell through the cell cycle. they control this by binding to a group of enzymes known as cycling dependent kinases.