A very low level of expression of the lac operon has to be present in the cell:
1. | When lactose is present | 2. | When lactose is absent |
3. | When glucose is absent | 4. | All the time |
The UTR [untranslated regions] in an mRNA:
1. | Are present only at 5’ end and are not required for efficient translation |
2. | Are present only at 3’ end and are not required for efficient translation |
3. | Are present at both 5’ and 3’ends and are not required for efficient translation |
4. | Are present at both 5’ and 3’ ends and are required for an efficient translation process |
Which of the following is not a feature of the double helix model of DNA?
1. | The two chains have anti-parallel polarity |
2. | A purine always comes opposite to a pyrimidine |
3. | The pitch of the DNA is 3.4 nm |
4. | The two chains are coiled in a left handed fashion |
Gene regulation in prokaryotes is carried out exclusively at the level of:
1. | Initiation of transcription |
2. | Post-transcriptional modifications |
3. | Translation |
4. | Post-translational modifications |
The lac operon is regarded as:
1. | Negative, Inducible | 2. | Negative, Repressible |
3. | Positive, Inducible | 4. | Positive, Repressible |
In RNA splicing:
1. | Exons are removed and introns are joined together |
2. | Introns are removed and exons are joined together |
3. | Cistrons are removed and introns are joined together |
4. | Introns are removed and Cistrons are joined together |
In most prokaryotes, the transcription unit is:
1. | Mono-cistronic | 2. | Poly-cistronic |
3. | Multi-cistronic | 4. | Uni-cistronic |
The last of 24 human chromosomes to be sequenced was:
1. Chromosome 1 and completed in 2003
2. Chromosome 1 and completed in 2006
3. Chromosome X and completed in 2003
4. Chromosome X and completed in 2006
Which of the following is not a feature of the human genome?
1. | The human genome contains 3164.7 million nucleotide bases. |
2. | The largest human gene of dystrophin has about 2.4 million bases. |
3. | The total number of genes in the human genome is much higher than the previous estimates. |
4. | Less than 2 % of the genome codes for proteins. |
Satellite DNA:
1. Form a small portion of the human genome
2. Code for proteins that are essential for survival
3. Code for proteins that are not essential for survival
4. Show a high degree of polymorphism