Molecular Biology Concepts Assessment

The video tutorial covers the fundamentals of gene expression and regulation, focusing on the structure and function of DNA and RNA. It explains the central dogma of molecular biology, detailing the processes of transcription and translation. The tutorial also explores DNA replication, gene regulation mechanisms, and the impact of mutations on genetic diversity. Additionally, it introduces key biotechnology techniques such as PCR and gene cloning.

Which of the following is NOT a component of nucleic acids?

• Phosphate group

• Pentose sugar

• Nitrogenous base

• Amino acid

What is the main structural difference between DNA and RNA?

• DNA is found in the cytoplasm, RNA is found in the nucleus

• DNA is single-stranded, RNA is double-stranded

• DNA has thymine, RNA has uracil

• DNA has ribose sugar, RNA has deoxyribose sugar

What type of bond holds the nitrogenous bases together in a DNA molecule?

• Ionic bonds

• Peptide bonds

• Covalent bonds

• Hydrogen bonds

During DNA replication, which enzyme is responsible for unwinding the DNA helix?

• Helicase

• DNA polymerase

• Primase

• Ligase

What is the role of mRNA in the process of translation?

• It carries amino acids to the ribosome

• It forms the structure of the ribosome

• It serves as a template for protein synthesis

• It unwinds the DNA helix

Which of the following modifications is added to the 5' end of mRNA?

• 5' cap

• Poly-A tail

• Intron

• Exon

What is the function of a repressor in an operon?

• It adds a methyl group to DNA

• It enhances the binding of RNA polymerase

• It removes introns from mRNA

• It prevents the binding of RNA polymerase

Which type of mutation involves the insertion or deletion of a nucleotide, altering the reading frame?

• Frameshift mutation

• Missense mutation

• Silent mutation

• Point mutation

What is the purpose of PCR (Polymerase Chain Reaction)?

• To separate DNA fragments by size

• To sequence the entire genome

• To cut DNA at specific sequences

• To amplify a specific DNA segment

In gel electrophoresis, which DNA fragments move the fastest?

• The shortest fragments

• The most negatively charged fragments

• The longest fragments

• The most positively charged fragments