Tag: molecular biology

Quizzes (15) Questions (122)

Questions Related to molecular biology

Multiple choice bio-chemistry nucleic acids central dogma transcription and gene expression molecular biology

Which one is RNA dependent DNA polymerase

  1. RNA polymerase I

  2. Tag polymerase

  3. DNA polymerase

  4. Reverse transcriptase
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Reverse transcriptase is the RNA-dependent DNA polymerase that synthesizes DNA from an RNA template. RNA polymerase I and DNA polymerase are not RNA-dependent. Tag polymerase appears to be a typo (likely Taq polymerase), which is a DNA-dependent DNA polymerase used in PCR.

Multiple choice bio-chemistry nucleic acids central dogma transcription and gene expression molecular biology

In a 3.2K bp long piece of DNA, 820 adenine bases were found. What would be the number of cytosine bases

  1. 1480

  2. 740

  3. 560

  4. 780
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In double-stranded DNA, A pairs with T and G pairs with C. If there are 820 adenine bases, there must be 820 thymine bases, totaling 1640 bases. The remaining bases are 3200 - 1640 = 1560, which are split equally between G and C, so 1560 / 2 = 780 cytosine bases.

Multiple choice bio-chemistry nucleic acids central dogma transcription and gene expression molecular biology

Teminious central dogma of protein synthesis is

  1. DNA DNA mRNA protein

  2. mRNA gRNA DNA Protein

  3. gRNA DNA mRNA Protein

  4. DNA gRNA mRNA Protein
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This represents the flow in retroviruses: genomic RNA (gRNA) is reverse transcribed to DNA, which is then transcribed to mRNA and translated to protein. Option A is standard replication, B is incorrect (gRNA to DNA requires reverse transcription), and D has incorrect flow order.

Multiple choice bio-chemistry nucleic acids central dogma transcription and gene expression molecular biology

Central dogma of molecular biology was modified with the discovery of

  1. Ligase

  2. RNA polymerase

  3. DNA polymerase

  4. Reverse transcriptase
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The central dogma originally stated DNA to RNA to protein. The discovery of reverse transcriptase showed that RNA can serve as a template for DNA synthesis, requiring a modification to the dogma.

Multiple choice bio-chemistry nucleic acids central dogma transcription and gene expression molecular biology

Enzyme responsible for replication of HIV in macrophages is 

  1. RNA polymerase

  2. DNA ligase

  3. DNA polymerase

  4. Reverse transcriptase
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Once inside a CD$ _4$ cell ( helper T cell ), HIV releases and uses reverse transcriptase  to convert its genetic material—HIV RNA—into HIV DNA. The conversion of HIV RNA to HIV DNA allows HIV to enter the CD$ _4$ cell nucleus and combine with the cell’s genetic material—cell DNA.

So, the correct answer is 'Reverse transcriptase'