Molecular Biology I Molecular Biology I Molecular Biology is the study of biological processes at the molecular level, primarily focusing on the interactions between various systems of a cell, including the interrelationships of DNA, RNA, and proteins, and their biosynthesis, regulation, and functions. 1 / 10 Which DNA repair mechanism is primarily responsible for repairing thymine dimers caused by ultraviolet (UV) light exposure? Base excision repair Nucleotide excision repair Mismatch repair Homologous recombination 2 / 10 Which of the following is a post-translational modification that can alter the function or localization of a protein? Splicing Capping Phosphorylation Polyadenylation 3 / 10 During DNA replication, which enzyme is responsible for synthesizing the RNA primer required for DNA polymerase to initiate replication? DNA ligase Primase DNA helicase RNA polymerase 4 / 10 In the context of gene regulation, what is the role of enhancers? They bind to the promoter region to initiate transcription. They increase the rate of transcription by interacting with transcription factors. They act as silencers to inhibit transcription. They are sites for ribosome binding during translation. 5 / 10 Which of the following processes involves the modification of mRNA transcripts by the addition of a 5′ cap and a poly-A tail? Transcription Translation RNA splicing RNA processing 6 / 10 Which protein complex is essential for the ubiquitin-proteasome pathway, where it tags proteins for degradation by attaching ubiquitin molecules? Ribosome Spliceosome Proteasome SCF complex (Skp, Cullin, F-box containing complex) 7 / 10 The CRISPR-Cas9 system is a revolutionary tool for genome editing. What is the role of the guide RNA (gRNA) in this system? It provides the Cas9 enzyme with energy. It binds to the target DNA sequence to guide the Cas9 enzyme. It synthesizes the new DNA strand. It repairs the DNA after cleavage. 8 / 10 Which type of RNA is involved in the process of RNA interference (RNAi) and is known to guide the silencing complex to complementary mRNA molecules, leading to their degradation or translational repression? Messenger RNA (mRNA) Ribosomal RNA (rRNA) Small interfering RNA (siRNA) Transfer RNA (tRNA) 9 / 10 In eukaryotic cells, the pre-initiation complex (PIC) is crucial for the initiation of transcription. Which of the following general transcription factors is responsible for recognizing and binding to the TATA box within the promoter region? TFIIH TFIID TFIIE TFIIB 10 / 10 Which enzyme is responsible for relieving the torsional strain ahead of the replication fork during DNA replication by creating temporary nicks in the DNA strand? DNA polymerase Helicase Topoisomerase Ligase Your score isThe average score is 0% 0% Restart quiz
